diff options
| -rw-r--r-- | .cargo_vcs_info.json | 6 | ||||
| -rw-r--r-- | Cargo.toml | 70 | ||||
| -rw-r--r-- | Cargo.toml.orig | 59 | ||||
| -rw-r--r-- | LICENSE-APACHE | 201 | ||||
| -rw-r--r-- | LICENSE-MIT | 23 | ||||
| -rw-r--r-- | README.md | 114 | ||||
| -rw-r--r-- | build.rs | 146 | ||||
| -rw-r--r-- | crates-io.md | 65 | ||||
| -rw-r--r-- | src/de/format.rs | 30 | ||||
| -rw-r--r-- | src/de/ignored_any.rs | 243 | ||||
| -rw-r--r-- | src/de/impls.rs | 2733 | ||||
| -rw-r--r-- | src/de/mod.rs | 2299 | ||||
| -rw-r--r-- | src/de/seed.rs | 19 | ||||
| -rw-r--r-- | src/de/utf8.rs | 46 | ||||
| -rw-r--r-- | src/de/value.rs | 1714 | ||||
| -rw-r--r-- | src/integer128.rs | 82 | ||||
| -rw-r--r-- | src/lib.rs | 334 | ||||
| -rw-r--r-- | src/macros.rs | 236 | ||||
| -rw-r--r-- | src/private/de.rs | 2995 | ||||
| -rw-r--r-- | src/private/doc.rs | 159 | ||||
| -rw-r--r-- | src/private/mod.rs | 50 | ||||
| -rw-r--r-- | src/private/ser.rs | 1310 | ||||
| -rw-r--r-- | src/private/size_hint.rs | 21 | ||||
| -rw-r--r-- | src/ser/fmt.rs | 174 | ||||
| -rw-r--r-- | src/ser/impls.rs | 983 | ||||
| -rw-r--r-- | src/ser/impossible.rs | 216 | ||||
| -rw-r--r-- | src/ser/mod.rs | 1988 | ||||
| -rw-r--r-- | src/std_error.rs | 48 |
28 files changed, 16364 insertions, 0 deletions
diff --git a/.cargo_vcs_info.json b/.cargo_vcs_info.json new file mode 100644 index 0000000..e57ffb4 --- /dev/null +++ b/.cargo_vcs_info.json @@ -0,0 +1,6 @@ +{ + "git": { + "sha1": "ccf9c6fc072378ea8c4f15df1024e258d35d6e61" + }, + "path_in_vcs": "serde" +}
\ No newline at end of file diff --git a/Cargo.toml b/Cargo.toml new file mode 100644 index 0000000..93acff3 --- /dev/null +++ b/Cargo.toml @@ -0,0 +1,70 @@ +# THIS FILE IS AUTOMATICALLY GENERATED BY CARGO +# +# When uploading crates to the registry Cargo will automatically +# "normalize" Cargo.toml files for maximal compatibility +# with all versions of Cargo and also rewrite `path` dependencies +# to registry (e.g., crates.io) dependencies. +# +# If you are reading this file be aware that the original Cargo.toml +# will likely look very different (and much more reasonable). +# See Cargo.toml.orig for the original contents. + +[package] +rust-version = "1.13" +name = "serde" +version = "1.0.152" +authors = [ + "Erick Tryzelaar <erick.tryzelaar@gmail.com>", + "David Tolnay <dtolnay@gmail.com>", +] +build = "build.rs" +include = [ + "build.rs", + "src/**/*.rs", + "crates-io.md", + "README.md", + "LICENSE-APACHE", + "LICENSE-MIT", +] +description = "A generic serialization/deserialization framework" +homepage = "https://serde.rs" +documentation = "https://docs.rs/serde" +readme = "crates-io.md" +keywords = [ + "serde", + "serialization", + "no_std", +] +categories = [ + "encoding", + "no-std", +] +license = "MIT OR Apache-2.0" +repository = "https://github.com/serde-rs/serde" + +[package.metadata.playground] +features = [ + "derive", + "rc", +] + +[package.metadata.docs.rs] +targets = ["x86_64-unknown-linux-gnu"] + +[lib] +doc-scrape-examples = false + +[dependencies.serde_derive] +version = "=1.0.152" +optional = true + +[dev-dependencies.serde_derive] +version = "1.0" + +[features] +alloc = [] +default = ["std"] +derive = ["serde_derive"] +rc = [] +std = [] +unstable = [] diff --git a/Cargo.toml.orig b/Cargo.toml.orig new file mode 100644 index 0000000..9c3bc58 --- /dev/null +++ b/Cargo.toml.orig @@ -0,0 +1,59 @@ +[package] +name = "serde" +version = "1.0.152" # remember to update html_root_url and serde_derive dependency +authors = ["Erick Tryzelaar <erick.tryzelaar@gmail.com>", "David Tolnay <dtolnay@gmail.com>"] +build = "build.rs" +categories = ["encoding", "no-std"] +description = "A generic serialization/deserialization framework" +documentation = "https://docs.rs/serde" +homepage = "https://serde.rs" +include = ["build.rs", "src/**/*.rs", "crates-io.md", "README.md", "LICENSE-APACHE", "LICENSE-MIT"] +keywords = ["serde", "serialization", "no_std"] +license = "MIT OR Apache-2.0" +readme = "crates-io.md" +repository = "https://github.com/serde-rs/serde" +rust-version = "1.13" + +[dependencies] +serde_derive = { version = "=1.0.152", optional = true, path = "../serde_derive" } + +[dev-dependencies] +serde_derive = { version = "1.0", path = "../serde_derive" } + +[lib] +doc-scrape-examples = false + +[package.metadata.playground] +features = ["derive", "rc"] + +[package.metadata.docs.rs] +targets = ["x86_64-unknown-linux-gnu"] + + +### FEATURES ################################################################# + +[features] +default = ["std"] + +# Provide derive(Serialize, Deserialize) macros. +derive = ["serde_derive"] + +# Provide impls for common standard library types like Vec<T> and HashMap<K, V>. +# Requires a dependency on the Rust standard library. +std = [] + +# Provide impls for types that require unstable functionality. For tracking and +# discussion of unstable functionality please refer to this issue: +# +# https://github.com/serde-rs/serde/issues/812 +unstable = [] + +# Provide impls for types in the Rust core allocation and collections library +# including String, Box<T>, Vec<T>, and Cow<T>. This is a subset of std but may +# be enabled without depending on all of std. +alloc = [] + +# Opt into impls for Rc<T> and Arc<T>. Serializing and deserializing these types +# does not preserve identity and may result in multiple copies of the same data. +# Be sure that this is what you want before enabling this feature. +rc = [] diff --git a/LICENSE-APACHE b/LICENSE-APACHE new file mode 100644 index 0000000..16fe87b --- /dev/null +++ b/LICENSE-APACHE @@ -0,0 +1,201 @@ + Apache License + Version 2.0, January 2004 + http://www.apache.org/licenses/ + +TERMS AND CONDITIONS FOR USE, REPRODUCTION, AND DISTRIBUTION + +1. Definitions. + + "License" shall mean the terms and conditions for use, reproduction, + and distribution as defined by Sections 1 through 9 of this document. + + "Licensor" shall mean the copyright owner or entity authorized by + the copyright owner that is granting the License. + + "Legal Entity" shall mean the union of the acting entity and all + other entities that control, are controlled by, or are under common + control with that entity. For the purposes of this definition, + "control" means (i) the power, direct or indirect, to cause the + direction or management of such entity, whether by contract or + otherwise, or (ii) ownership of fifty percent (50%) or more of the + outstanding shares, or (iii) beneficial ownership of such entity. + + "You" (or "Your") shall mean an individual or Legal Entity + exercising permissions granted by this License. + + "Source" form shall mean the preferred form for making modifications, + including but not limited to software source code, documentation + source, and configuration files. + + "Object" form shall mean any form resulting from mechanical + transformation or translation of a Source form, including but + not limited to compiled object code, generated documentation, + and conversions to other media types. + + "Work" shall mean the work of authorship, whether in Source or + Object form, made available under the License, as indicated by a + copyright notice that is included in or attached to the work + (an example is provided in the Appendix below). + + "Derivative Works" shall mean any work, whether in Source or Object + form, that is based on (or derived from) the Work and for which the + editorial revisions, annotations, elaborations, or other modifications + represent, as a whole, an original work of authorship. For the purposes + of this License, Derivative Works shall not include works that remain + separable from, or merely link (or bind by name) to the interfaces of, + the Work and Derivative Works thereof. + + "Contribution" shall mean any work of authorship, including + the original version of the Work and any modifications or additions + to that Work or Derivative Works thereof, that is intentionally + submitted to Licensor for inclusion in the Work by the copyright owner + or by an individual or Legal Entity authorized to submit on behalf of + the copyright owner. For the purposes of this definition, "submitted" + means any form of electronic, verbal, or written communication sent + to the Licensor or its representatives, including but not limited to + communication on electronic mailing lists, source code control systems, + and issue tracking systems that are managed by, or on behalf of, the + Licensor for the purpose of discussing and improving the Work, but + excluding communication that is conspicuously marked or otherwise + designated in writing by the copyright owner as "Not a Contribution." + + "Contributor" shall mean Licensor and any individual or Legal Entity + on behalf of whom a Contribution has been received by Licensor and + subsequently incorporated within the Work. + +2. Grant of Copyright License. Subject to the terms and conditions of + this License, each Contributor hereby grants to You a perpetual, + worldwide, non-exclusive, no-charge, royalty-free, irrevocable + copyright license to reproduce, prepare Derivative Works of, + publicly display, publicly perform, sublicense, and distribute the + Work and such Derivative Works in Source or Object form. + +3. Grant of Patent License. Subject to the terms and conditions of + this License, each Contributor hereby grants to You a perpetual, + worldwide, non-exclusive, no-charge, royalty-free, irrevocable + (except as stated in this section) patent license to make, have made, + use, offer to sell, sell, import, and otherwise transfer the Work, + where such license applies only to those patent claims licensable + by such Contributor that are necessarily infringed by their + Contribution(s) alone or by combination of their Contribution(s) + with the Work to which such Contribution(s) was submitted. If You + institute patent litigation against any entity (including a + cross-claim or counterclaim in a lawsuit) alleging that the Work + or a Contribution incorporated within the Work constitutes direct + or contributory patent infringement, then any patent licenses + granted to You under this License for that Work shall terminate + as of the date such litigation is filed. + +4. Redistribution. You may reproduce and distribute copies of the + Work or Derivative Works thereof in any medium, with or without + modifications, and in Source or Object form, provided that You + meet the following conditions: + + (a) You must give any other recipients of the Work or + Derivative Works a copy of this License; and + + (b) You must cause any modified files to carry prominent notices + stating that You changed the files; and + + (c) You must retain, in the Source form of any Derivative Works + that You distribute, all copyright, patent, trademark, and + attribution notices from the Source form of the Work, + excluding those notices that do not pertain to any part of + the Derivative Works; and + + (d) If the Work includes a "NOTICE" text file as part of its + distribution, then any Derivative Works that You distribute must + include a readable copy of the attribution notices contained + within such NOTICE file, excluding those notices that do not + pertain to any part of the Derivative Works, in at least one + of the following places: within a NOTICE text file distributed + as part of the Derivative Works; within the Source form or + documentation, if provided along with the Derivative Works; or, + within a display generated by the Derivative Works, if and + wherever such third-party notices normally appear. The contents + of the NOTICE file are for informational purposes only and + do not modify the License. You may add Your own attribution + notices within Derivative Works that You distribute, alongside + or as an addendum to the NOTICE text from the Work, provided + that such additional attribution notices cannot be construed + as modifying the License. + + You may add Your own copyright statement to Your modifications and + may provide additional or different license terms and conditions + for use, reproduction, or distribution of Your modifications, or + for any such Derivative Works as a whole, provided Your use, + reproduction, and distribution of the Work otherwise complies with + the conditions stated in this License. + +5. Submission of Contributions. Unless You explicitly state otherwise, + any Contribution intentionally submitted for inclusion in the Work + by You to the Licensor shall be under the terms and conditions of + this License, without any additional terms or conditions. + Notwithstanding the above, nothing herein shall supersede or modify + the terms of any separate license agreement you may have executed + with Licensor regarding such Contributions. + +6. Trademarks. This License does not grant permission to use the trade + names, trademarks, service marks, or product names of the Licensor, + except as required for reasonable and customary use in describing the + origin of the Work and reproducing the content of the NOTICE file. + +7. Disclaimer of Warranty. Unless required by applicable law or + agreed to in writing, Licensor provides the Work (and each + Contributor provides its Contributions) on an "AS IS" BASIS, + WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or + implied, including, without limitation, any warranties or conditions + of TITLE, NON-INFRINGEMENT, MERCHANTABILITY, or FITNESS FOR A + PARTICULAR PURPOSE. You are solely responsible for determining the + appropriateness of using or redistributing the Work and assume any + risks associated with Your exercise of permissions under this License. + +8. Limitation of Liability. In no event and under no legal theory, + whether in tort (including negligence), contract, or otherwise, + unless required by applicable law (such as deliberate and grossly + negligent acts) or agreed to in writing, shall any Contributor be + liable to You for damages, including any direct, indirect, special, + incidental, or consequential damages of any character arising as a + result of this License or out of the use or inability to use the + Work (including but not limited to damages for loss of goodwill, + work stoppage, computer failure or malfunction, or any and all + other commercial damages or losses), even if such Contributor + has been advised of the possibility of such damages. + +9. Accepting Warranty or Additional Liability. While redistributing + the Work or Derivative Works thereof, You may choose to offer, + and charge a fee for, acceptance of support, warranty, indemnity, + or other liability obligations and/or rights consistent with this + License. However, in accepting such obligations, You may act only + on Your own behalf and on Your sole responsibility, not on behalf + of any other Contributor, and only if You agree to indemnify, + defend, and hold each Contributor harmless for any liability + incurred by, or claims asserted against, such Contributor by reason + of your accepting any such warranty or additional liability. + +END OF TERMS AND CONDITIONS + +APPENDIX: How to apply the Apache License to your work. + + To apply the Apache License to your work, attach the following + boilerplate notice, with the fields enclosed by brackets "[]" + replaced with your own identifying information. (Don't include + the brackets!) The text should be enclosed in the appropriate + comment syntax for the file format. We also recommend that a + file or class name and description of purpose be included on the + same "printed page" as the copyright notice for easier + identification within third-party archives. + +Copyright [yyyy] [name of copyright owner] + +Licensed under the Apache License, Version 2.0 (the "License"); +you may not use this file except in compliance with the License. +You may obtain a copy of the License at + + http://www.apache.org/licenses/LICENSE-2.0 + +Unless required by applicable law or agreed to in writing, software +distributed under the License is distributed on an "AS IS" BASIS, +WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. +See the License for the specific language governing permissions and +limitations under the License. diff --git a/LICENSE-MIT b/LICENSE-MIT new file mode 100644 index 0000000..31aa793 --- /dev/null +++ b/LICENSE-MIT @@ -0,0 +1,23 @@ +Permission is hereby granted, free of charge, to any +person obtaining a copy of this software and associated +documentation files (the "Software"), to deal in the +Software without restriction, including without +limitation the rights to use, copy, modify, merge, +publish, distribute, sublicense, and/or sell copies of +the Software, and to permit persons to whom the Software +is furnished to do so, subject to the following +conditions: + +The above copyright notice and this permission notice +shall be included in all copies or substantial portions +of the Software. + +THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF +ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED +TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A +PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT +SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY +CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION +OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR +IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER +DEALINGS IN THE SOFTWARE. diff --git a/README.md b/README.md new file mode 100644 index 0000000..c3f6575 --- /dev/null +++ b/README.md @@ -0,0 +1,114 @@ +# Serde   [![Build Status]][actions] [![Latest Version]][crates.io] [![serde: rustc 1.13+]][Rust 1.13] [![serde_derive: rustc 1.31+]][Rust 1.31] + +[Build Status]: https://img.shields.io/github/actions/workflow/status/serde-rs/serde/ci.yml?branch=master +[actions]: https://github.com/serde-rs/serde/actions?query=branch%3Amaster +[Latest Version]: https://img.shields.io/crates/v/serde.svg +[crates.io]: https://crates.io/crates/serde +[serde: rustc 1.13+]: https://img.shields.io/badge/serde-rustc_1.13+-lightgray.svg +[serde_derive: rustc 1.31+]: https://img.shields.io/badge/serde_derive-rustc_1.31+-lightgray.svg +[Rust 1.13]: https://blog.rust-lang.org/2016/11/10/Rust-1.13.html +[Rust 1.31]: https://blog.rust-lang.org/2018/12/06/Rust-1.31-and-rust-2018.html + +**Serde is a framework for *ser*ializing and *de*serializing Rust data structures efficiently and generically.** + +--- + +You may be looking for: + +- [An overview of Serde](https://serde.rs/) +- [Data formats supported by Serde](https://serde.rs/#data-formats) +- [Setting up `#[derive(Serialize, Deserialize)]`](https://serde.rs/derive.html) +- [Examples](https://serde.rs/examples.html) +- [API documentation](https://docs.rs/serde) +- [Release notes](https://github.com/serde-rs/serde/releases) + +## Serde in action + +<details> +<summary> +Click to show Cargo.toml. +<a href="https://play.rust-lang.org/?edition=2018&gist=72755f28f99afc95e01d63174b28c1f5" target="_blank">Run this code in the playground.</a> +</summary> + +```toml +[dependencies] + +# The core APIs, including the Serialize and Deserialize traits. Always +# required when using Serde. The "derive" feature is only required when +# using #[derive(Serialize, Deserialize)] to make Serde work with structs +# and enums defined in your crate. +serde = { version = "1.0", features = ["derive"] } + +# Each data format lives in its own crate; the sample code below uses JSON +# but you may be using a different one. +serde_json = "1.0" +``` + +</details> +<p></p> + +```rust +use serde::{Serialize, Deserialize}; + +#[derive(Serialize, Deserialize, Debug)] +struct Point { + x: i32, + y: i32, +} + +fn main() { + let point = Point { x: 1, y: 2 }; + + // Convert the Point to a JSON string. + let serialized = serde_json::to_string(&point).unwrap(); + + // Prints serialized = {"x":1,"y":2} + println!("serialized = {}", serialized); + + // Convert the JSON string back to a Point. + let deserialized: Point = serde_json::from_str(&serialized).unwrap(); + + // Prints deserialized = Point { x: 1, y: 2 } + println!("deserialized = {:?}", deserialized); +} +``` + +## Getting help + +Serde is one of the most widely used Rust libraries so any place that Rustaceans +congregate will be able to help you out. For chat, consider trying the +[#rust-questions] or [#rust-beginners] channels of the unofficial community +Discord (invite: <https://discord.gg/rust-lang-community>), the [#rust-usage] or +[#beginners] channels of the official Rust Project Discord (invite: +<https://discord.gg/rust-lang>), or the [#general][zulip] stream in Zulip. For +asynchronous, consider the [\[rust\] tag on StackOverflow][stackoverflow], the +[/r/rust] subreddit which has a pinned weekly easy questions post, or the Rust +[Discourse forum][discourse]. It's acceptable to file a support issue in this +repo but they tend not to get as many eyes as any of the above and may get +closed without a response after some time. + +[#rust-questions]: https://discord.com/channels/273534239310479360/274215136414400513 +[#rust-beginners]: https://discord.com/channels/273534239310479360/273541522815713281 +[#rust-usage]: https://discord.com/channels/442252698964721669/443150878111694848 +[#beginners]: https://discord.com/channels/442252698964721669/448238009733742612 +[zulip]: https://rust-lang.zulipchat.com/#narrow/stream/122651-general +[stackoverflow]: https://stackoverflow.com/questions/tagged/rust +[/r/rust]: https://www.reddit.com/r/rust +[discourse]: https://users.rust-lang.org + +<br> + +#### License + +<sup> +Licensed under either of <a href="LICENSE-APACHE">Apache License, Version +2.0</a> or <a href="LICENSE-MIT">MIT license</a> at your option. +</sup> + +<br> + +<sub> +Unless you explicitly state otherwise, any contribution intentionally submitted +for inclusion in Serde by you, as defined in the Apache-2.0 license, shall be +dual licensed as above, without any additional terms or conditions. +</sub> diff --git a/build.rs b/build.rs new file mode 100644 index 0000000..ccbddd2 --- /dev/null +++ b/build.rs @@ -0,0 +1,146 @@ +use std::env; +use std::process::Command; +use std::str::{self, FromStr}; + +// The rustc-cfg strings below are *not* public API. Please let us know by +// opening a GitHub issue if your build environment requires some way to enable +// these cfgs other than by executing our build script. +fn main() { + println!("cargo:rerun-if-changed=build.rs"); + + let minor = match rustc_minor_version() { + Some(minor) => minor, + None => return, + }; + + let target = env::var("TARGET").unwrap(); + let emscripten = target == "asmjs-unknown-emscripten" || target == "wasm32-unknown-emscripten"; + + // std::collections::Bound was stabilized in Rust 1.17 + // but it was moved to core::ops later in Rust 1.26: + // https://doc.rust-lang.org/core/ops/enum.Bound.html + if minor < 26 { + println!("cargo:rustc-cfg=no_ops_bound"); + if minor < 17 { + println!("cargo:rustc-cfg=no_collections_bound"); + } + } + + // core::cmp::Reverse stabilized in Rust 1.19: + // https://doc.rust-lang.org/stable/core/cmp/struct.Reverse.html + if minor < 19 { + println!("cargo:rustc-cfg=no_core_reverse"); + } + + // CString::into_boxed_c_str and PathBuf::into_boxed_path stabilized in Rust 1.20: + // https://doc.rust-lang.org/std/ffi/struct.CString.html#method.into_boxed_c_str + // https://doc.rust-lang.org/std/path/struct.PathBuf.html#method.into_boxed_path + if minor < 20 { + println!("cargo:rustc-cfg=no_de_boxed_c_str"); + println!("cargo:rustc-cfg=no_de_boxed_path"); + } + + // From<Box<T>> for Rc<T> / Arc<T> stabilized in Rust 1.21: + // https://doc.rust-lang.org/std/rc/struct.Rc.html#impl-From<Box<T>> + // https://doc.rust-lang.org/std/sync/struct.Arc.html#impl-From<Box<T>> + if minor < 21 { + println!("cargo:rustc-cfg=no_de_rc_dst"); + } + + // Duration available in core since Rust 1.25: + // https://blog.rust-lang.org/2018/03/29/Rust-1.25.html#library-stabilizations + if minor < 25 { + println!("cargo:rustc-cfg=no_core_duration"); + } + + // 128-bit integers stabilized in Rust 1.26: + // https://blog.rust-lang.org/2018/05/10/Rust-1.26.html + // + // Disabled on Emscripten targets before Rust 1.40 since + // Emscripten did not support 128-bit integers until Rust 1.40 + // (https://github.com/rust-lang/rust/pull/65251) + if minor < 26 || emscripten && minor < 40 { + println!("cargo:rustc-cfg=no_integer128"); + } + + // Inclusive ranges methods stabilized in Rust 1.27: + // https://github.com/rust-lang/rust/pull/50758 + // Also Iterator::try_for_each: + // https://blog.rust-lang.org/2018/06/21/Rust-1.27.html#library-stabilizations + if minor < 27 { + println!("cargo:rustc-cfg=no_range_inclusive"); + println!("cargo:rustc-cfg=no_iterator_try_fold"); + } + + // Non-zero integers stabilized in Rust 1.28: + // https://blog.rust-lang.org/2018/08/02/Rust-1.28.html#library-stabilizations + if minor < 28 { + println!("cargo:rustc-cfg=no_num_nonzero"); + } + + // Current minimum supported version of serde_derive crate is Rust 1.31. + if minor < 31 { + println!("cargo:rustc-cfg=no_serde_derive"); + } + + // TryFrom, Atomic types, non-zero signed integers, and SystemTime::checked_add + // stabilized in Rust 1.34: + // https://blog.rust-lang.org/2019/04/11/Rust-1.34.0.html#tryfrom-and-tryinto + // https://blog.rust-lang.org/2019/04/11/Rust-1.34.0.html#library-stabilizations + if minor < 34 { + println!("cargo:rustc-cfg=no_core_try_from"); + println!("cargo:rustc-cfg=no_num_nonzero_signed"); + println!("cargo:rustc-cfg=no_systemtime_checked_add"); + println!("cargo:rustc-cfg=no_relaxed_trait_bounds"); + } + + // Support for #[cfg(target_has_atomic = "...")] stabilized in Rust 1.60. + if minor < 60 { + println!("cargo:rustc-cfg=no_target_has_atomic"); + // Allowlist of archs that support std::sync::atomic module. This is + // based on rustc's compiler/rustc_target/src/spec/*.rs. + let has_atomic64 = target.starts_with("x86_64") + || target.starts_with("i686") + || target.starts_with("aarch64") + || target.starts_with("powerpc64") + || target.starts_with("sparc64") + || target.starts_with("mips64el") + || target.starts_with("riscv64"); + let has_atomic32 = has_atomic64 || emscripten; + if minor < 34 || !has_atomic64 { + println!("cargo:rustc-cfg=no_std_atomic64"); + } + if minor < 34 || !has_atomic32 { + println!("cargo:rustc-cfg=no_std_atomic"); + } + } +} + +fn rustc_minor_version() -> Option<u32> { + let rustc = match env::var_os("RUSTC") { + Some(rustc) => rustc, + None => return None, + }; + + let output = match Command::new(rustc).arg("--version").output() { + Ok(output) => output, + Err(_) => return None, + }; + + let version = match str::from_utf8(&output.stdout) { + Ok(version) => version, + Err(_) => return None, + }; + + let mut pieces = version.split('.'); + if pieces.next() != Some("rustc 1") { + return None; + } + + let next = match pieces.next() { + Some(next) => next, + None => return None, + }; + + u32::from_str(next).ok() +} diff --git a/crates-io.md b/crates-io.md new file mode 100644 index 0000000..6e0ec28 --- /dev/null +++ b/crates-io.md @@ -0,0 +1,65 @@ +<!-- Serde readme rendered on crates.io --> + +**Serde is a framework for *ser*ializing and *de*serializing Rust data structures efficiently and generically.** + +--- + +You may be looking for: + +- [An overview of Serde](https://serde.rs/) +- [Data formats supported by Serde](https://serde.rs/#data-formats) +- [Setting up `#[derive(Serialize, Deserialize)]`](https://serde.rs/derive.html) +- [Examples](https://serde.rs/examples.html) +- [API documentation](https://docs.rs/serde) +- [Release notes](https://github.com/serde-rs/serde/releases) + +## Serde in action + +```rust +use serde::{Serialize, Deserialize}; + +#[derive(Serialize, Deserialize, Debug)] +struct Point { + x: i32, + y: i32, +} + +fn main() { + let point = Point { x: 1, y: 2 }; + + // Convert the Point to a JSON string. + let serialized = serde_json::to_string(&point).unwrap(); + + // Prints serialized = {"x":1,"y":2} + println!("serialized = {}", serialized); + + // Convert the JSON string back to a Point. + let deserialized: Point = serde_json::from_str(&serialized).unwrap(); + + // Prints deserialized = Point { x: 1, y: 2 } + println!("deserialized = {:?}", deserialized); +} +``` + +## Getting help + +Serde is one of the most widely used Rust libraries so any place that Rustaceans +congregate will be able to help you out. For chat, consider trying the +[#rust-questions] or [#rust-beginners] channels of the unofficial community +Discord (invite: <https://discord.gg/rust-lang-community>, the [#rust-usage] or +[#beginners] channels of the official Rust Project Discord (invite: +<https://discord.gg/rust-lang>), or the [#general][zulip] stream in Zulip. For +asynchronous, consider the [\[rust\] tag on StackOverflow][stackoverflow], the +[/r/rust] subreddit which has a pinned weekly easy questions post, or the Rust +[Discourse forum][discourse]. It's acceptable to file a support issue in this +repo but they tend not to get as many eyes as any of the above and may get +closed without a response after some time. + +[#rust-questions]: https://discord.com/channels/273534239310479360/274215136414400513 +[#rust-beginners]: https://discord.com/channels/273534239310479360/273541522815713281 +[#rust-usage]: https://discord.com/channels/442252698964721669/443150878111694848 +[#beginners]: https://discord.com/channels/442252698964721669/448238009733742612 +[zulip]: https://rust-lang.zulipchat.com/#narrow/stream/122651-general +[stackoverflow]: https://stackoverflow.com/questions/tagged/rust +[/r/rust]: https://www.reddit.com/r/rust +[discourse]: https://users.rust-lang.org diff --git a/src/de/format.rs b/src/de/format.rs new file mode 100644 index 0000000..f14580b --- /dev/null +++ b/src/de/format.rs @@ -0,0 +1,30 @@ +use lib::fmt::{self, Write}; +use lib::str; + +pub(super) struct Buf<'a> { + bytes: &'a mut [u8], + offset: usize, +} + +impl<'a> Buf<'a> { + pub fn new(bytes: &'a mut [u8]) -> Self { + Buf { bytes, offset: 0 } + } + + pub fn as_str(&self) -> &str { + let slice = &self.bytes[..self.offset]; + unsafe { str::from_utf8_unchecked(slice) } + } +} + +impl<'a> Write for Buf<'a> { + fn write_str(&mut self, s: &str) -> fmt::Result { + if self.offset + s.len() > self.bytes.len() { + Err(fmt::Error) + } else { + self.bytes[self.offset..self.offset + s.len()].copy_from_slice(s.as_bytes()); + self.offset += s.len(); + Ok(()) + } + } +} diff --git a/src/de/ignored_any.rs b/src/de/ignored_any.rs new file mode 100644 index 0000000..9ed438e --- /dev/null +++ b/src/de/ignored_any.rs @@ -0,0 +1,243 @@ +use lib::*; + +use de::{ + Deserialize, Deserializer, EnumAccess, Error, MapAccess, SeqAccess, VariantAccess, Visitor, +}; + +/// An efficient way of discarding data from a deserializer. +/// +/// Think of this like `serde_json::Value` in that it can be deserialized from +/// any type, except that it does not store any information about the data that +/// gets deserialized. +/// +/// ```edition2018 +/// use std::fmt; +/// use std::marker::PhantomData; +/// +/// use serde::de::{ +/// self, Deserialize, DeserializeSeed, Deserializer, IgnoredAny, SeqAccess, Visitor, +/// }; +/// +/// /// A seed that can be used to deserialize only the `n`th element of a sequence +/// /// while efficiently discarding elements of any type before or after index `n`. +/// /// +/// /// For example to deserialize only the element at index 3: +/// /// +/// /// ``` +/// /// NthElement::new(3).deserialize(deserializer) +/// /// ``` +/// pub struct NthElement<T> { +/// n: usize, +/// marker: PhantomData<T>, +/// } +/// +/// impl<T> NthElement<T> { +/// pub fn new(n: usize) -> Self { +/// NthElement { +/// n: n, +/// marker: PhantomData, +/// } +/// } +/// } +/// +/// impl<'de, T> Visitor<'de> for NthElement<T> +/// where +/// T: Deserialize<'de>, +/// { +/// type Value = T; +/// +/// fn expecting(&self, formatter: &mut fmt::Formatter) -> fmt::Result { +/// write!( +/// formatter, +/// "a sequence in which we care about element {}", +/// self.n +/// ) +/// } +/// +/// fn visit_seq<A>(self, mut seq: A) -> Result<Self::Value, A::Error> +/// where +/// A: SeqAccess<'de>, +/// { +/// // Skip over the first `n` elements. +/// for i in 0..self.n { +/// // It is an error if the sequence ends before we get to element `n`. +/// if seq.next_element::<IgnoredAny>()?.is_none() { +/// return Err(de::Error::invalid_length(i, &self)); +/// } +/// } +/// +/// // Deserialize the one we care about. +/// let nth = match seq.next_element()? { +/// Some(nth) => nth, +/// None => { +/// return Err(de::Error::invalid_length(self.n, &self)); +/// } +/// }; +/// +/// // Skip over any remaining elements in the sequence after `n`. +/// while let Some(IgnoredAny) = seq.next_element()? { +/// // ignore +/// } +/// +/// Ok(nth) +/// } +/// } +/// +/// impl<'de, T> DeserializeSeed<'de> for NthElement<T> +/// where +/// T: Deserialize<'de>, +/// { +/// type Value = T; +/// +/// fn deserialize<D>(self, deserializer: D) -> Result<Self::Value, D::Error> +/// where +/// D: Deserializer<'de>, +/// { +/// deserializer.deserialize_seq(self) +/// } +/// } +/// +/// # fn example<'de, D>(deserializer: D) -> Result<(), D::Error> +/// # where +/// # D: Deserializer<'de>, +/// # { +/// // Deserialize only the sequence element at index 3 from this deserializer. +/// // The element at index 3 is required to be a string. Elements before and +/// // after index 3 are allowed to be of any type. +/// let s: String = NthElement::new(3).deserialize(deserializer)?; +/// # Ok(()) +/// # } +/// ``` +#[derive(Copy, Clone, Debug, Default)] +pub struct IgnoredAny; + +impl<'de> Visitor<'de> for IgnoredAny { + type Value = IgnoredAny; + + fn expecting(&self, formatter: &mut fmt::Formatter) -> fmt::Result { + formatter.write_str("anything at all") + } + + #[inline] + fn visit_bool<E>(self, x: bool) -> Result<Self::Value, E> { + let _ = x; + Ok(IgnoredAny) + } + + #[inline] + fn visit_i64<E>(self, x: i64) -> Result<Self::Value, E> { + let _ = x; + Ok(IgnoredAny) + } + + serde_if_integer128! { + #[inline] + fn visit_i128<E>(self, x: i128) -> Result<Self::Value, E> { + let _ = x; + Ok(IgnoredAny) + } + } + + #[inline] + fn visit_u64<E>(self, x: u64) -> Result<Self::Value, E> { + let _ = x; + Ok(IgnoredAny) + } + + serde_if_integer128! { + #[inline] + fn visit_u128<E>(self, x: u128) -> Result<Self::Value, E> { + let _ = x; + Ok(IgnoredAny) + } + } + + #[inline] + fn visit_f64<E>(self, x: f64) -> Result<Self::Value, E> { + let _ = x; + Ok(IgnoredAny) + } + + #[inline] + fn visit_str<E>(self, s: &str) -> Result<Self::Value, E> + where + E: Error, + { + let _ = s; + Ok(IgnoredAny) + } + + #[inline] + fn visit_none<E>(self) -> Result<Self::Value, E> { + Ok(IgnoredAny) + } + + #[inline] + fn visit_some<D>(self, deserializer: D) -> Result<Self::Value, D::Error> + where + D: Deserializer<'de>, + { + IgnoredAny::deserialize(deserializer) + } + + #[inline] + fn visit_newtype_struct<D>(self, deserializer: D) -> Result<Self::Value, D::Error> + where + D: Deserializer<'de>, + { + IgnoredAny::deserialize(deserializer) + } + + #[inline] + fn visit_unit<E>(self) -> Result<Self::Value, E> { + Ok(IgnoredAny) + } + + #[inline] + fn visit_seq<A>(self, mut seq: A) -> Result<Self::Value, A::Error> + where + A: SeqAccess<'de>, + { + while let Some(IgnoredAny) = try!(seq.next_element()) { + // Gobble + } + Ok(IgnoredAny) + } + + #[inline] + fn visit_map<A>(self, mut map: A) -> Result<Self::Value, A::Error> + where + A: MapAccess<'de>, + { + while let Some((IgnoredAny, IgnoredAny)) = try!(map.next_entry()) { + // Gobble + } + Ok(IgnoredAny) + } + + #[inline] + fn visit_bytes<E>(self, bytes: &[u8]) -> Result<Self::Value, E> + where + E: Error, + { + let _ = bytes; + Ok(IgnoredAny) + } + + fn visit_enum<A>(self, data: A) -> Result<Self::Value, A::Error> + where + A: EnumAccess<'de>, + { + try!(data.variant::<IgnoredAny>()).1.newtype_variant() + } +} + +impl<'de> Deserialize<'de> for IgnoredAny { + #[inline] + fn deserialize<D>(deserializer: D) -> Result<IgnoredAny, D::Error> + where + D: Deserializer<'de>, + { + deserializer.deserialize_ignored_any(IgnoredAny) + } +} diff --git a/src/de/impls.rs b/src/de/impls.rs new file mode 100644 index 0000000..a257d9e --- /dev/null +++ b/src/de/impls.rs @@ -0,0 +1,2733 @@ +use lib::*; + +use de::{ + Deserialize, Deserializer, EnumAccess, Error, SeqAccess, Unexpected, VariantAccess, Visitor, +}; + +#[cfg(any(feature = "std", feature = "alloc", not(no_core_duration)))] +use de::MapAccess; + +use seed::InPlaceSeed; + +#[cfg(any(feature = "std", feature = "alloc"))] +use __private::size_hint; + +//////////////////////////////////////////////////////////////////////////////// + +struct UnitVisitor; + +impl<'de> Visitor<'de> for UnitVisitor { + type Value = (); + + fn expecting(&self, formatter: &mut fmt::Formatter) -> fmt::Result { + formatter.write_str("unit") + } + + fn visit_unit<E>(self) -> Result<Self::Value, E> + where + E: Error, + { + Ok(()) + } +} + +impl<'de> Deserialize<'de> for () { + fn deserialize<D>(deserializer: D) -> Result<Self, D::Error> + where + D: Deserializer<'de>, + { + deserializer.deserialize_unit(UnitVisitor) + } +} + +#[cfg(feature = "unstable")] +impl<'de> Deserialize<'de> for ! { + fn deserialize<D>(_deserializer: D) -> Result<Self, D::Error> + where + D: Deserializer<'de>, + { + Err(Error::custom("cannot deserialize `!`")) + } +} + +//////////////////////////////////////////////////////////////////////////////// + +struct BoolVisitor; + +impl<'de> Visitor<'de> for BoolVisitor { + type Value = bool; + + fn expecting(&self, formatter: &mut fmt::Formatter) -> fmt::Result { + formatter.write_str("a boolean") + } + + fn visit_bool<E>(self, v: bool) -> Result<Self::Value, E> + where + E: Error, + { + Ok(v) + } +} + +impl<'de> Deserialize<'de> for bool { + fn deserialize<D>(deserializer: D) -> Result<Self, D::Error> + where + D: Deserializer<'de>, + { + deserializer.deserialize_bool(BoolVisitor) + } +} + +//////////////////////////////////////////////////////////////////////////////// + +macro_rules! impl_deserialize_num { + ($primitive:ident, $nonzero:ident $(cfg($($cfg:tt)*))*, $deserialize:ident $($method:ident!($($val:ident : $visit:ident)*);)*) => { + impl_deserialize_num!($primitive, $deserialize $($method!($($val : $visit)*);)*); + + #[cfg(all(not(no_num_nonzero), $($($cfg)*)*))] + impl<'de> Deserialize<'de> for num::$nonzero { + fn deserialize<D>(deserializer: D) -> Result<Self, D::Error> + where + D: Deserializer<'de>, + { + struct NonZeroVisitor; + + impl<'de> Visitor<'de> for NonZeroVisitor { + type Value = num::$nonzero; + + fn expecting(&self, formatter: &mut fmt::Formatter) -> fmt::Result { + formatter.write_str(concat!("a nonzero ", stringify!($primitive))) + } + + $($($method!(nonzero $primitive $val : $visit);)*)* + } + + deserializer.$deserialize(NonZeroVisitor) + } + } + }; + + ($primitive:ident, $deserialize:ident $($method:ident!($($val:ident : $visit:ident)*);)*) => { + impl<'de> Deserialize<'de> for $primitive { + #[inline] + fn deserialize<D>(deserializer: D) -> Result<Self, D::Error> + where + D: Deserializer<'de>, + { + struct PrimitiveVisitor; + + impl<'de> Visitor<'de> for PrimitiveVisitor { + type Value = $primitive; + + fn expecting(&self, formatter: &mut fmt::Formatter) -> fmt::Result { + formatter.write_str(stringify!($primitive)) + } + + $($($method!($val : $visit);)*)* + } + + deserializer.$deserialize(PrimitiveVisitor) + } + } + }; +} + +macro_rules! num_self { + ($ty:ident : $visit:ident) => { + #[inline] + fn $visit<E>(self, v: $ty) -> Result<Self::Value, E> + where + E: Error, + { + Ok(v) + } + }; + + (nonzero $primitive:ident $ty:ident : $visit:ident) => { + fn $visit<E>(self, v: $ty) -> Result<Self::Value, E> + where + E: Error, + { + if let Some(nonzero) = Self::Value::new(v) { + Ok(nonzero) + } else { + Err(Error::invalid_value(Unexpected::Unsigned(0), &self)) + } + } + }; +} + +macro_rules! num_as_self { + ($ty:ident : $visit:ident) => { + #[inline] + fn $visit<E>(self, v: $ty) -> Result<Self::Value, E> + where + E: Error, + { + Ok(v as Self::Value) + } + }; + + (nonzero $primitive:ident $ty:ident : $visit:ident) => { + fn $visit<E>(self, v: $ty) -> Result<Self::Value, E> + where + E: Error, + { + if let Some(nonzero) = Self::Value::new(v as $primitive) { + Ok(nonzero) + } else { + Err(Error::invalid_value(Unexpected::Unsigned(0), &self)) + } + } + }; +} + +macro_rules! int_to_int { + ($ty:ident : $visit:ident) => { + #[inline] + fn $visit<E>(self, v: $ty) -> Result<Self::Value, E> + where + E: Error, + { + if Self::Value::min_value() as i64 <= v as i64 + && v as i64 <= Self::Value::max_value() as i64 + { + Ok(v as Self::Value) + } else { + Err(Error::invalid_value(Unexpected::Signed(v as i64), &self)) + } + } + }; + + (nonzero $primitive:ident $ty:ident : $visit:ident) => { + fn $visit<E>(self, v: $ty) -> Result<Self::Value, E> + where + E: Error, + { + if $primitive::min_value() as i64 <= v as i64 + && v as i64 <= $primitive::max_value() as i64 + { + if let Some(nonzero) = Self::Value::new(v as $primitive) { + return Ok(nonzero); + } + } + Err(Error::invalid_value(Unexpected::Signed(v as i64), &self)) + } + }; +} + +macro_rules! int_to_uint { + ($ty:ident : $visit:ident) => { + #[inline] + fn $visit<E>(self, v: $ty) -> Result<Self::Value, E> + where + E: Error, + { + if 0 <= v && v as u64 <= Self::Value::max_value() as u64 { + Ok(v as Self::Value) + } else { + Err(Error::invalid_value(Unexpected::Signed(v as i64), &self)) + } + } + }; + + (nonzero $primitive:ident $ty:ident : $visit:ident) => { + fn $visit<E>(self, v: $ty) -> Result<Self::Value, E> + where + E: Error, + { + if 0 < v && v as u64 <= $primitive::max_value() as u64 { + if let Some(nonzero) = Self::Value::new(v as $primitive) { + return Ok(nonzero); + } + } + Err(Error::invalid_value(Unexpected::Signed(v as i64), &self)) + } + }; +} + +macro_rules! uint_to_self { + ($ty:ident : $visit:ident) => { + #[inline] + fn $visit<E>(self, v: $ty) -> Result<Self::Value, E> + where + E: Error, + { + if v as u64 <= Self::Value::max_value() as u64 { + Ok(v as Self::Value) + } else { + Err(Error::invalid_value(Unexpected::Unsigned(v as u64), &self)) + } + } + }; + + (nonzero $primitive:ident $ty:ident : $visit:ident) => { + fn $visit<E>(self, v: $ty) -> Result<Self::Value, E> + where + E: Error, + { + if v as u64 <= $primitive::max_value() as u64 { + if let Some(nonzero) = Self::Value::new(v as $primitive) { + return Ok(nonzero); + } + } + Err(Error::invalid_value(Unexpected::Unsigned(v as u64), &self)) + } + }; +} + +impl_deserialize_num! { + i8, NonZeroI8 cfg(not(no_num_nonzero_signed)), deserialize_i8 + num_self!(i8:visit_i8); + int_to_int!(i16:visit_i16 i32:visit_i32 i64:visit_i64); + uint_to_self!(u8:visit_u8 u16:visit_u16 u32:visit_u32 u64:visit_u64); +} + +impl_deserialize_num! { + i16, NonZeroI16 cfg(not(no_num_nonzero_signed)), deserialize_i16 + num_self!(i16:visit_i16); + num_as_self!(i8:visit_i8); + int_to_int!(i32:visit_i32 i64:visit_i64); + uint_to_self!(u8:visit_u8 u16:visit_u16 u32:visit_u32 u64:visit_u64); +} + +impl_deserialize_num! { + i32, NonZeroI32 cfg(not(no_num_nonzero_signed)), deserialize_i32 + num_self!(i32:visit_i32); + num_as_self!(i8:visit_i8 i16:visit_i16); + int_to_int!(i64:visit_i64); + uint_to_self!(u8:visit_u8 u16:visit_u16 u32:visit_u32 u64:visit_u64); +} + +impl_deserialize_num! { + i64, NonZeroI64 cfg(not(no_num_nonzero_signed)), deserialize_i64 + num_self!(i64:visit_i64); + num_as_self!(i8:visit_i8 i16:visit_i16 i32:visit_i32); + uint_to_self!(u8:visit_u8 u16:visit_u16 u32:visit_u32 u64:visit_u64); +} + +impl_deserialize_num! { + isize, NonZeroIsize cfg(not(no_num_nonzero_signed)), deserialize_i64 + num_as_self!(i8:visit_i8 i16:visit_i16); + int_to_int!(i32:visit_i32 i64:visit_i64); + uint_to_self!(u8:visit_u8 u16:visit_u16 u32:visit_u32 u64:visit_u64); +} + +impl_deserialize_num! { + u8, NonZeroU8, deserialize_u8 + num_self!(u8:visit_u8); + int_to_uint!(i8:visit_i8 i16:visit_i16 i32:visit_i32 i64:visit_i64); + uint_to_self!(u16:visit_u16 u32:visit_u32 u64:visit_u64); +} + +impl_deserialize_num! { + u16, NonZeroU16, deserialize_u16 + num_self!(u16:visit_u16); + num_as_self!(u8:visit_u8); + int_to_uint!(i8:visit_i8 i16:visit_i16 i32:visit_i32 i64:visit_i64); + uint_to_self!(u32:visit_u32 u64:visit_u64); +} + +impl_deserialize_num! { + u32, NonZeroU32, deserialize_u32 + num_self!(u32:visit_u32); + num_as_self!(u8:visit_u8 u16:visit_u16); + int_to_uint!(i8:visit_i8 i16:visit_i16 i32:visit_i32 i64:visit_i64); + uint_to_self!(u64:visit_u64); +} + +impl_deserialize_num! { + u64, NonZeroU64, deserialize_u64 + num_self!(u64:visit_u64); + num_as_self!(u8:visit_u8 u16:visit_u16 u32:visit_u32); + int_to_uint!(i8:visit_i8 i16:visit_i16 i32:visit_i32 i64:visit_i64); +} + +impl_deserialize_num! { + usize, NonZeroUsize, deserialize_u64 + num_as_self!(u8:visit_u8 u16:visit_u16); + int_to_uint!(i8:visit_i8 i16:visit_i16 i32:visit_i32 i64:visit_i64); + uint_to_self!(u32:visit_u32 u64:visit_u64); +} + +impl_deserialize_num! { + f32, deserialize_f32 + num_self!(f32:visit_f32); + num_as_self!(f64:visit_f64); + num_as_self!(i8:visit_i8 i16:visit_i16 i32:visit_i32 i64:visit_i64); + num_as_self!(u8:visit_u8 u16:visit_u16 u32:visit_u32 u64:visit_u64); +} + +impl_deserialize_num! { + f64, deserialize_f64 + num_self!(f64:visit_f64); + num_as_self!(f32:visit_f32); + num_as_self!(i8:visit_i8 i16:visit_i16 i32:visit_i32 i64:visit_i64); + num_as_self!(u8:visit_u8 u16:visit_u16 u32:visit_u32 u64:visit_u64); +} + +serde_if_integer128! { + macro_rules! num_128 { + ($ty:ident : $visit:ident) => { + fn $visit<E>(self, v: $ty) -> Result<Self::Value, E> + where + E: Error, + { + if v as i128 >= Self::Value::min_value() as i128 + && v as u128 <= Self::Value::max_value() as u128 + { + Ok(v as Self::Value) + } else { + Err(Error::invalid_value( + Unexpected::Other(stringify!($ty)), + &self, + )) + } + } + }; + + (nonzero $primitive:ident $ty:ident : $visit:ident) => { + fn $visit<E>(self, v: $ty) -> Result<Self::Value, E> + where + E: Error, + { + if v as i128 >= $primitive::min_value() as i128 + && v as u128 <= $primitive::max_value() as u128 + { + if let Some(nonzero) = Self::Value::new(v as $primitive) { + Ok(nonzero) + } else { + Err(Error::invalid_value(Unexpected::Unsigned(0), &self)) + } + } else { + Err(Error::invalid_value( + Unexpected::Other(stringify!($ty)), + &self, + )) + } + } + }; + } + + impl_deserialize_num! { + i128, NonZeroI128 cfg(not(no_num_nonzero_signed)), deserialize_i128 + num_self!(i128:visit_i128); + num_as_self!(i8:visit_i8 i16:visit_i16 i32:visit_i32 i64:visit_i64); + num_as_self!(u8:visit_u8 u16:visit_u16 u32:visit_u32 u64:visit_u64); + num_128!(u128:visit_u128); + } + + impl_deserialize_num! { + u128, NonZeroU128, deserialize_u128 + num_self!(u128:visit_u128); + num_as_self!(u8:visit_u8 u16:visit_u16 u32:visit_u32 u64:visit_u64); + int_to_uint!(i8:visit_i8 i16:visit_i16 i32:visit_i32 i64:visit_i64); + num_128!(i128:visit_i128); + } +} + +//////////////////////////////////////////////////////////////////////////////// + +struct CharVisitor; + +impl<'de> Visitor<'de> for CharVisitor { + type Value = char; + + fn expecting(&self, formatter: &mut fmt::Formatter) -> fmt::Result { + formatter.write_str("a character") + } + + #[inline] + fn visit_char<E>(self, v: char) -> Result<Self::Value, E> + where + E: Error, + { + Ok(v) + } + + #[inline] + fn visit_str<E>(self, v: &str) -> Result<Self::Value, E> + where + E: Error, + { + let mut iter = v.chars(); + match (iter.next(), iter.next()) { + (Some(c), None) => Ok(c), + _ => Err(Error::invalid_value(Unexpected::Str(v), &self)), + } + } +} + +impl<'de> Deserialize<'de> for char { + #[inline] + fn deserialize<D>(deserializer: D) -> Result<Self, D::Error> + where + D: Deserializer<'de>, + { + deserializer.deserialize_char(CharVisitor) + } +} + +//////////////////////////////////////////////////////////////////////////////// + +#[cfg(any(feature = "std", feature = "alloc"))] +struct StringVisitor; +#[cfg(any(feature = "std", feature = "alloc"))] +struct StringInPlaceVisitor<'a>(&'a mut String); + +#[cfg(any(feature = "std", feature = "alloc"))] +impl<'de> Visitor<'de> for StringVisitor { + type Value = String; + + fn expecting(&self, formatter: &mut fmt::Formatter) -> fmt::Result { + formatter.write_str("a string") + } + + fn visit_str<E>(self, v: &str) -> Result<Self::Value, E> + where + E: Error, + { + Ok(v.to_owned()) + } + + fn visit_string<E>(self, v: String) -> Result<Self::Value, E> + where + E: Error, + { + Ok(v) + } + + fn visit_bytes<E>(self, v: &[u8]) -> Result<Self::Value, E> + where + E: Error, + { + match str::from_utf8(v) { + Ok(s) => Ok(s.to_owned()), + Err(_) => Err(Error::invalid_value(Unexpected::Bytes(v), &self)), + } + } + + fn visit_byte_buf<E>(self, v: Vec<u8>) -> Result<Self::Value, E> + where + E: Error, + { + match String::from_utf8(v) { + Ok(s) => Ok(s), + Err(e) => Err(Error::invalid_value( + Unexpected::Bytes(&e.into_bytes()), + &self, + )), + } + } +} + +#[cfg(any(feature = "std", feature = "alloc"))] +impl<'a, 'de> Visitor<'de> for StringInPlaceVisitor<'a> { + type Value = (); + + fn expecting(&self, formatter: &mut fmt::Formatter) -> fmt::Result { + formatter.write_str("a string") + } + + fn visit_str<E>(self, v: &str) -> Result<Self::Value, E> + where + E: Error, + { + self.0.clear(); + self.0.push_str(v); + Ok(()) + } + + fn visit_string<E>(self, v: String) -> Result<Self::Value, E> + where + E: Error, + { + *self.0 = v; + Ok(()) + } + + fn visit_bytes<E>(self, v: &[u8]) -> Result<Self::Value, E> + where + E: Error, + { + match str::from_utf8(v) { + Ok(s) => { + self.0.clear(); + self.0.push_str(s); + Ok(()) + } + Err(_) => Err(Error::invalid_value(Unexpected::Bytes(v), &self)), + } + } + + fn visit_byte_buf<E>(self, v: Vec<u8>) -> Result<Self::Value, E> + where + E: Error, + { + match String::from_utf8(v) { + Ok(s) => { + *self.0 = s; + Ok(()) + } + Err(e) => Err(Error::invalid_value( + Unexpected::Bytes(&e.into_bytes()), + &self, + )), + } + } +} + +#[cfg(any(feature = "std", feature = "alloc"))] +impl<'de> Deserialize<'de> for String { + fn deserialize<D>(deserializer: D) -> Result<Self, D::Error> + where + D: Deserializer<'de>, + { + deserializer.deserialize_string(StringVisitor) + } + + fn deserialize_in_place<D>(deserializer: D, place: &mut Self) -> Result<(), D::Error> + where + D: Deserializer<'de>, + { + deserializer.deserialize_string(StringInPlaceVisitor(place)) + } +} + +//////////////////////////////////////////////////////////////////////////////// + +struct StrVisitor; + +impl<'a> Visitor<'a> for StrVisitor { + type Value = &'a str; + + fn expecting(&self, formatter: &mut fmt::Formatter) -> fmt::Result { + formatter.write_str("a borrowed string") + } + + fn visit_borrowed_str<E>(self, v: &'a str) -> Result<Self::Value, E> + where + E: Error, + { + Ok(v) // so easy + } + + fn visit_borrowed_bytes<E>(self, v: &'a [u8]) -> Result<Self::Value, E> + where + E: Error, + { + str::from_utf8(v).map_err(|_| Error::invalid_value(Unexpected::Bytes(v), &self)) + } +} + +impl<'de: 'a, 'a> Deserialize<'de> for &'a str { + fn deserialize<D>(deserializer: D) -> Result<Self, D::Error> + where + D: Deserializer<'de>, + { + deserializer.deserialize_str(StrVisitor) + } +} + +//////////////////////////////////////////////////////////////////////////////// + +struct BytesVisitor; + +impl<'a> Visitor<'a> for BytesVisitor { + type Value = &'a [u8]; + + fn expecting(&self, formatter: &mut fmt::Formatter) -> fmt::Result { + formatter.write_str("a borrowed byte array") + } + + fn visit_borrowed_bytes<E>(self, v: &'a [u8]) -> Result<Self::Value, E> + where + E: Error, + { + Ok(v) + } + + fn visit_borrowed_str<E>(self, v: &'a str) -> Result<Self::Value, E> + where + E: Error, + { + Ok(v.as_bytes()) + } +} + +impl<'de: 'a, 'a> Deserialize<'de> for &'a [u8] { + fn deserialize<D>(deserializer: D) -> Result<Self, D::Error> + where + D: Deserializer<'de>, + { + deserializer.deserialize_bytes(BytesVisitor) + } +} + +//////////////////////////////////////////////////////////////////////////////// + +#[cfg(feature = "std")] +struct CStringVisitor; + +#[cfg(feature = "std")] +impl<'de> Visitor<'de> for CStringVisitor { + type Value = CString; + + fn expecting(&self, formatter: &mut fmt::Formatter) -> fmt::Result { + formatter.write_str("byte array") + } + + fn visit_seq<A>(self, mut seq: A) -> Result<Self::Value, A::Error> + where + A: SeqAccess<'de>, + { + let len = size_hint::cautious(seq.size_hint()); + let mut values = Vec::with_capacity(len); + + while let Some(value) = try!(seq.next_element()) { + values.push(value); + } + + CString::new(values).map_err(Error::custom) + } + + fn visit_bytes<E>(self, v: &[u8]) -> Result<Self::Value, E> + where + E: Error, + { + CString::new(v).map_err(Error::custom) + } + + fn visit_byte_buf<E>(self, v: Vec<u8>) -> Result<Self::Value, E> + where + E: Error, + { + CString::new(v).map_err(Error::custom) + } + + fn visit_str<E>(self, v: &str) -> Result<Self::Value, E> + where + E: Error, + { + CString::new(v).map_err(Error::custom) + } + + fn visit_string<E>(self, v: String) -> Result<Self::Value, E> + where + E: Error, + { + CString::new(v).map_err(Error::custom) + } +} + +#[cfg(feature = "std")] +impl<'de> Deserialize<'de> for CString { + fn deserialize<D>(deserializer: D) -> Result<Self, D::Error> + where + D: Deserializer<'de>, + { + deserializer.deserialize_byte_buf(CStringVisitor) + } +} + +macro_rules! forwarded_impl { + ( + $(#[doc = $doc:tt])* + ($($id:ident),*), $ty:ty, $func:expr + ) => { + $(#[doc = $doc])* + impl<'de $(, $id : Deserialize<'de>,)*> Deserialize<'de> for $ty { + fn deserialize<D>(deserializer: D) -> Result<Self, D::Error> + where + D: Deserializer<'de>, + { + Deserialize::deserialize(deserializer).map($func) + } + } + } +} + +#[cfg(all(feature = "std", not(no_de_boxed_c_str)))] +forwarded_impl!((), Box<CStr>, CString::into_boxed_c_str); + +#[cfg(not(no_core_reverse))] +forwarded_impl!((T), Reverse<T>, Reverse); + +//////////////////////////////////////////////////////////////////////////////// + +struct OptionVisitor<T> { + marker: PhantomData<T>, +} + +impl<'de, T> Visitor<'de> for OptionVisitor<T> +where + T: Deserialize<'de>, +{ + type Value = Option<T>; + + fn expecting(&self, formatter: &mut fmt::Formatter) -> fmt::Result { + formatter.write_str("option") + } + + #[inline] + fn visit_unit<E>(self) -> Result<Self::Value, E> + where + E: Error, + { + Ok(None) + } + + #[inline] + fn visit_none<E>(self) -> Result<Self::Value, E> + where + E: Error, + { + Ok(None) + } + + #[inline] + fn visit_some<D>(self, deserializer: D) -> Result<Self::Value, D::Error> + where + D: Deserializer<'de>, + { + T::deserialize(deserializer).map(Some) + } + + fn __private_visit_untagged_option<D>(self, deserializer: D) -> Result<Self::Value, ()> + where + D: Deserializer<'de>, + { + Ok(T::deserialize(deserializer).ok()) + } +} + +impl<'de, T> Deserialize<'de> for Option<T> +where + T: Deserialize<'de>, +{ + fn deserialize<D>(deserializer: D) -> Result<Self, D::Error> + where + D: Deserializer<'de>, + { + deserializer.deserialize_option(OptionVisitor { + marker: PhantomData, + }) + } + + // The Some variant's repr is opaque, so we can't play cute tricks with its + // tag to have deserialize_in_place build the content in place unconditionally. + // + // FIXME: investigate whether branching on the old value being Some to + // deserialize_in_place the value is profitable (probably data-dependent?) +} + +//////////////////////////////////////////////////////////////////////////////// + +struct PhantomDataVisitor<T: ?Sized> { + marker: PhantomData<T>, +} + +impl<'de, T: ?Sized> Visitor<'de> for PhantomDataVisitor<T> { + type Value = PhantomData<T>; + + fn expecting(&self, formatter: &mut fmt::Formatter) -> fmt::Result { + formatter.write_str("unit") + } + + #[inline] + fn visit_unit<E>(self) -> Result<Self::Value, E> + where + E: Error, + { + Ok(PhantomData) + } +} + +impl<'de, T: ?Sized> Deserialize<'de> for PhantomData<T> { + fn deserialize<D>(deserializer: D) -> Result<Self, D::Error> + where + D: Deserializer<'de>, + { + let visitor = PhantomDataVisitor { + marker: PhantomData, + }; + deserializer.deserialize_unit_struct("PhantomData", visitor) + } +} + +//////////////////////////////////////////////////////////////////////////////// + +#[cfg(any(feature = "std", feature = "alloc"))] +macro_rules! seq_impl { + ( + $ty:ident <T $(: $tbound1:ident $(+ $tbound2:ident)*)* $(, $typaram:ident : $bound1:ident $(+ $bound2:ident)*)*>, + $access:ident, + $clear:expr, + $with_capacity:expr, + $reserve:expr, + $insert:expr + ) => { + impl<'de, T $(, $typaram)*> Deserialize<'de> for $ty<T $(, $typaram)*> + where + T: Deserialize<'de> $(+ $tbound1 $(+ $tbound2)*)*, + $($typaram: $bound1 $(+ $bound2)*,)* + { + fn deserialize<D>(deserializer: D) -> Result<Self, D::Error> + where + D: Deserializer<'de>, + { + struct SeqVisitor<T $(, $typaram)*> { + marker: PhantomData<$ty<T $(, $typaram)*>>, + } + + impl<'de, T $(, $typaram)*> Visitor<'de> for SeqVisitor<T $(, $typaram)*> + where + T: Deserialize<'de> $(+ $tbound1 $(+ $tbound2)*)*, + $($typaram: $bound1 $(+ $bound2)*,)* + { + type Value = $ty<T $(, $typaram)*>; + + fn expecting(&self, formatter: &mut fmt::Formatter) -> fmt::Result { + formatter.write_str("a sequence") + } + + #[inline] + fn visit_seq<A>(self, mut $access: A) -> Result<Self::Value, A::Error> + where + A: SeqAccess<'de>, + { + let mut values = $with_capacity; + + while let Some(value) = try!($access.next_element()) { + $insert(&mut values, value); + } + + Ok(values) + } + } + + let visitor = SeqVisitor { marker: PhantomData }; + deserializer.deserialize_seq(visitor) + } + + fn deserialize_in_place<D>(deserializer: D, place: &mut Self) -> Result<(), D::Error> + where + D: Deserializer<'de>, + { + struct SeqInPlaceVisitor<'a, T: 'a $(, $typaram: 'a)*>(&'a mut $ty<T $(, $typaram)*>); + + impl<'a, 'de, T $(, $typaram)*> Visitor<'de> for SeqInPlaceVisitor<'a, T $(, $typaram)*> + where + T: Deserialize<'de> $(+ $tbound1 $(+ $tbound2)*)*, + $($typaram: $bound1 $(+ $bound2)*,)* + { + type Value = (); + + fn expecting(&self, formatter: &mut fmt::Formatter) -> fmt::Result { + formatter.write_str("a sequence") + } + + #[inline] + fn visit_seq<A>(mut self, mut $access: A) -> Result<Self::Value, A::Error> + where + A: SeqAccess<'de>, + { + $clear(&mut self.0); + $reserve(&mut self.0, size_hint::cautious($access.size_hint())); + + // FIXME: try to overwrite old values here? (Vec, VecDeque, LinkedList) + while let Some(value) = try!($access.next_element()) { + $insert(&mut self.0, value); + } + + Ok(()) + } + } + + deserializer.deserialize_seq(SeqInPlaceVisitor(place)) + } + } + } +} + +// Dummy impl of reserve +#[cfg(any(feature = "std", feature = "alloc"))] +fn nop_reserve<T>(_seq: T, _n: usize) {} + +#[cfg(any(feature = "std", feature = "alloc"))] +seq_impl!( + BinaryHeap<T: Ord>, + seq, + BinaryHeap::clear, + BinaryHeap::with_capacity(size_hint::cautious(seq.size_hint())), + BinaryHeap::reserve, + BinaryHeap::push +); + +#[cfg(any(feature = "std", feature = "alloc"))] +seq_impl!( + BTreeSet<T: Eq + Ord>, + seq, + BTreeSet::clear, + BTreeSet::new(), + nop_reserve, + BTreeSet::insert +); + +#[cfg(any(feature = "std", feature = "alloc"))] +seq_impl!( + LinkedList<T>, + seq, + LinkedList::clear, + LinkedList::new(), + nop_reserve, + LinkedList::push_back +); + +#[cfg(feature = "std")] +seq_impl!( + HashSet<T: Eq + Hash, S: BuildHasher + Default>, + seq, + HashSet::clear, + HashSet::with_capacity_and_hasher(size_hint::cautious(seq.size_hint()), S::default()), + HashSet::reserve, + HashSet::insert); + +#[cfg(any(feature = "std", feature = "alloc"))] +seq_impl!( + VecDeque<T>, + seq, + VecDeque::clear, + VecDeque::with_capacity(size_hint::cautious(seq.size_hint())), + VecDeque::reserve, + VecDeque::push_back +); + +//////////////////////////////////////////////////////////////////////////////// + +#[cfg(any(feature = "std", feature = "alloc"))] +impl<'de, T> Deserialize<'de> for Vec<T> +where + T: Deserialize<'de>, +{ + fn deserialize<D>(deserializer: D) -> Result<Self, D::Error> + where + D: Deserializer<'de>, + { + struct VecVisitor<T> { + marker: PhantomData<T>, + } + + impl<'de, T> Visitor<'de> for VecVisitor<T> + where + T: Deserialize<'de>, + { + type Value = Vec<T>; + + fn expecting(&self, formatter: &mut fmt::Formatter) -> fmt::Result { + formatter.write_str("a sequence") + } + + fn visit_seq<A>(self, mut seq: A) -> Result<Self::Value, A::Error> + where + A: SeqAccess<'de>, + { + let mut values = Vec::with_capacity(size_hint::cautious(seq.size_hint())); + + while let Some(value) = try!(seq.next_element()) { + values.push(value); + } + + Ok(values) + } + } + + let visitor = VecVisitor { + marker: PhantomData, + }; + deserializer.deserialize_seq(visitor) + } + + fn deserialize_in_place<D>(deserializer: D, place: &mut Self) -> Result<(), D::Error> + where + D: Deserializer<'de>, + { + struct VecInPlaceVisitor<'a, T: 'a>(&'a mut Vec<T>); + + impl<'a, 'de, T> Visitor<'de> for VecInPlaceVisitor<'a, T> + where + T: Deserialize<'de>, + { + type Value = (); + + fn expecting(&self, formatter: &mut fmt::Formatter) -> fmt::Result { + formatter.write_str("a sequence") + } + + fn visit_seq<A>(self, mut seq: A) -> Result<Self::Value, A::Error> + where + A: SeqAccess<'de>, + { + let hint = size_hint::cautious(seq.size_hint()); + if let Some(additional) = hint.checked_sub(self.0.len()) { + self.0.reserve(additional); + } + + for i in 0..self.0.len() { + let next = { + let next_place = InPlaceSeed(&mut self.0[i]); + try!(seq.next_element_seed(next_place)) + }; + if next.is_none() { + self.0.truncate(i); + return Ok(()); + } + } + + while let Some(value) = try!(seq.next_element()) { + self.0.push(value); + } + + Ok(()) + } + } + + deserializer.deserialize_seq(VecInPlaceVisitor(place)) + } +} + +//////////////////////////////////////////////////////////////////////////////// + +struct ArrayVisitor<A> { + marker: PhantomData<A>, +} +struct ArrayInPlaceVisitor<'a, A: 'a>(&'a mut A); + +impl<A> ArrayVisitor<A> { + fn new() -> Self { + ArrayVisitor { + marker: PhantomData, + } + } +} + +impl<'de, T> Visitor<'de> for ArrayVisitor<[T; 0]> { + type Value = [T; 0]; + + fn expecting(&self, formatter: &mut fmt::Formatter) -> fmt::Result { + formatter.write_str("an empty array") + } + + #[inline] + fn visit_seq<A>(self, _: A) -> Result<Self::Value, A::Error> + where + A: SeqAccess<'de>, + { + Ok([]) + } +} + +// Does not require T: Deserialize<'de>. +impl<'de, T> Deserialize<'de> for [T; 0] { + fn deserialize<D>(deserializer: D) -> Result<Self, D::Error> + where + D: Deserializer<'de>, + { + deserializer.deserialize_tuple(0, ArrayVisitor::<[T; 0]>::new()) + } +} + +macro_rules! array_impls { + ($($len:expr => ($($n:tt)+))+) => { + $( + impl<'de, T> Visitor<'de> for ArrayVisitor<[T; $len]> + where + T: Deserialize<'de>, + { + type Value = [T; $len]; + + fn expecting(&self, formatter: &mut fmt::Formatter) -> fmt::Result { + formatter.write_str(concat!("an array of length ", $len)) + } + + #[inline] + fn visit_seq<A>(self, mut seq: A) -> Result<Self::Value, A::Error> + where + A: SeqAccess<'de>, + { + Ok([$( + match try!(seq.next_element()) { + Some(val) => val, + None => return Err(Error::invalid_length($n, &self)), + } + ),+]) + } + } + + impl<'a, 'de, T> Visitor<'de> for ArrayInPlaceVisitor<'a, [T; $len]> + where + T: Deserialize<'de>, + { + type Value = (); + + fn expecting(&self, formatter: &mut fmt::Formatter) -> fmt::Result { + formatter.write_str(concat!("an array of length ", $len)) + } + + #[inline] + fn visit_seq<A>(self, mut seq: A) -> Result<Self::Value, A::Error> + where + A: SeqAccess<'de>, + { + let mut fail_idx = None; + for (idx, dest) in self.0[..].iter_mut().enumerate() { + if try!(seq.next_element_seed(InPlaceSeed(dest))).is_none() { + fail_idx = Some(idx); + break; + } + } + if let Some(idx) = fail_idx { + return Err(Error::invalid_length(idx, &self)); + } + Ok(()) + } + } + + impl<'de, T> Deserialize<'de> for [T; $len] + where + T: Deserialize<'de>, + { + fn deserialize<D>(deserializer: D) -> Result<Self, D::Error> + where + D: Deserializer<'de>, + { + deserializer.deserialize_tuple($len, ArrayVisitor::<[T; $len]>::new()) + } + + fn deserialize_in_place<D>(deserializer: D, place: &mut Self) -> Result<(), D::Error> + where + D: Deserializer<'de>, + { + deserializer.deserialize_tuple($len, ArrayInPlaceVisitor(place)) + } + } + )+ + } +} + +array_impls! { + 1 => (0) + 2 => (0 1) + 3 => (0 1 2) + 4 => (0 1 2 3) + 5 => (0 1 2 3 4) + 6 => (0 1 2 3 4 5) + 7 => (0 1 2 3 4 5 6) + 8 => (0 1 2 3 4 5 6 7) + 9 => (0 1 2 3 4 5 6 7 8) + 10 => (0 1 2 3 4 5 6 7 8 9) + 11 => (0 1 2 3 4 5 6 7 8 9 10) + 12 => (0 1 2 3 4 5 6 7 8 9 10 11) + 13 => (0 1 2 3 4 5 6 7 8 9 10 11 12) + 14 => (0 1 2 3 4 5 6 7 8 9 10 11 12 13) + 15 => (0 1 2 3 4 5 6 7 8 9 10 11 12 13 14) + 16 => (0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15) + 17 => (0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16) + 18 => (0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17) + 19 => (0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18) + 20 => (0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19) + 21 => (0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20) + 22 => (0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21) + 23 => (0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22) + 24 => (0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23) + 25 => (0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24) + 26 => (0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25) + 27 => (0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26) + 28 => (0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27) + 29 => (0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28) + 30 => (0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29) + 31 => (0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30) + 32 => (0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31) +} + +//////////////////////////////////////////////////////////////////////////////// + +macro_rules! tuple_impls { + ($($len:tt => ($($n:tt $name:ident)+))+) => { + $( + impl<'de, $($name: Deserialize<'de>),+> Deserialize<'de> for ($($name,)+) { + #[inline] + fn deserialize<D>(deserializer: D) -> Result<Self, D::Error> + where + D: Deserializer<'de>, + { + struct TupleVisitor<$($name,)+> { + marker: PhantomData<($($name,)+)>, + } + + impl<'de, $($name: Deserialize<'de>),+> Visitor<'de> for TupleVisitor<$($name,)+> { + type Value = ($($name,)+); + + fn expecting(&self, formatter: &mut fmt::Formatter) -> fmt::Result { + formatter.write_str(concat!("a tuple of size ", $len)) + } + + #[inline] + #[allow(non_snake_case)] + fn visit_seq<A>(self, mut seq: A) -> Result<Self::Value, A::Error> + where + A: SeqAccess<'de>, + { + $( + let $name = match try!(seq.next_element()) { + Some(value) => value, + None => return Err(Error::invalid_length($n, &self)), + }; + )+ + + Ok(($($name,)+)) + } + } + + deserializer.deserialize_tuple($len, TupleVisitor { marker: PhantomData }) + } + + #[inline] + fn deserialize_in_place<D>(deserializer: D, place: &mut Self) -> Result<(), D::Error> + where + D: Deserializer<'de>, + { + struct TupleInPlaceVisitor<'a, $($name: 'a,)+>(&'a mut ($($name,)+)); + + impl<'a, 'de, $($name: Deserialize<'de>),+> Visitor<'de> for TupleInPlaceVisitor<'a, $($name,)+> { + type Value = (); + + fn expecting(&self, formatter: &mut fmt::Formatter) -> fmt::Result { + formatter.write_str(concat!("a tuple of size ", $len)) + } + + #[inline] + #[allow(non_snake_case)] + fn visit_seq<A>(self, mut seq: A) -> Result<Self::Value, A::Error> + where + A: SeqAccess<'de>, + { + $( + if try!(seq.next_element_seed(InPlaceSeed(&mut (self.0).$n))).is_none() { + return Err(Error::invalid_length($n, &self)); + } + )+ + + Ok(()) + } + } + + deserializer.deserialize_tuple($len, TupleInPlaceVisitor(place)) + } + } + )+ + } +} + +tuple_impls! { + 1 => (0 T0) + 2 => (0 T0 1 T1) + 3 => (0 T0 1 T1 2 T2) + 4 => (0 T0 1 T1 2 T2 3 T3) + 5 => (0 T0 1 T1 2 T2 3 T3 4 T4) + 6 => (0 T0 1 T1 2 T2 3 T3 4 T4 5 T5) + 7 => (0 T0 1 T1 2 T2 3 T3 4 T4 5 T5 6 T6) + 8 => (0 T0 1 T1 2 T2 3 T3 4 T4 5 T5 6 T6 7 T7) + 9 => (0 T0 1 T1 2 T2 3 T3 4 T4 5 T5 6 T6 7 T7 8 T8) + 10 => (0 T0 1 T1 2 T2 3 T3 4 T4 5 T5 6 T6 7 T7 8 T8 9 T9) + 11 => (0 T0 1 T1 2 T2 3 T3 4 T4 5 T5 6 T6 7 T7 8 T8 9 T9 10 T10) + 12 => (0 T0 1 T1 2 T2 3 T3 4 T4 5 T5 6 T6 7 T7 8 T8 9 T9 10 T10 11 T11) + 13 => (0 T0 1 T1 2 T2 3 T3 4 T4 5 T5 6 T6 7 T7 8 T8 9 T9 10 T10 11 T11 12 T12) + 14 => (0 T0 1 T1 2 T2 3 T3 4 T4 5 T5 6 T6 7 T7 8 T8 9 T9 10 T10 11 T11 12 T12 13 T13) + 15 => (0 T0 1 T1 2 T2 3 T3 4 T4 5 T5 6 T6 7 T7 8 T8 9 T9 10 T10 11 T11 12 T12 13 T13 14 T14) + 16 => (0 T0 1 T1 2 T2 3 T3 4 T4 5 T5 6 T6 7 T7 8 T8 9 T9 10 T10 11 T11 12 T12 13 T13 14 T14 15 T15) +} + +//////////////////////////////////////////////////////////////////////////////// + +#[cfg(any(feature = "std", feature = "alloc"))] +macro_rules! map_impl { + ( + $ty:ident <K $(: $kbound1:ident $(+ $kbound2:ident)*)*, V $(, $typaram:ident : $bound1:ident $(+ $bound2:ident)*)*>, + $access:ident, + $with_capacity:expr + ) => { + impl<'de, K, V $(, $typaram)*> Deserialize<'de> for $ty<K, V $(, $typaram)*> + where + K: Deserialize<'de> $(+ $kbound1 $(+ $kbound2)*)*, + V: Deserialize<'de>, + $($typaram: $bound1 $(+ $bound2)*),* + { + fn deserialize<D>(deserializer: D) -> Result<Self, D::Error> + where + D: Deserializer<'de>, + { + struct MapVisitor<K, V $(, $typaram)*> { + marker: PhantomData<$ty<K, V $(, $typaram)*>>, + } + + impl<'de, K, V $(, $typaram)*> Visitor<'de> for MapVisitor<K, V $(, $typaram)*> + where + K: Deserialize<'de> $(+ $kbound1 $(+ $kbound2)*)*, + V: Deserialize<'de>, + $($typaram: $bound1 $(+ $bound2)*),* + { + type Value = $ty<K, V $(, $typaram)*>; + + fn expecting(&self, formatter: &mut fmt::Formatter) -> fmt::Result { + formatter.write_str("a map") + } + + #[inline] + fn visit_map<A>(self, mut $access: A) -> Result<Self::Value, A::Error> + where + A: MapAccess<'de>, + { + let mut values = $with_capacity; + + while let Some((key, value)) = try!($access.next_entry()) { + values.insert(key, value); + } + + Ok(values) + } + } + + let visitor = MapVisitor { marker: PhantomData }; + deserializer.deserialize_map(visitor) + } + } + } +} + +#[cfg(any(feature = "std", feature = "alloc"))] +map_impl!( + BTreeMap<K: Ord, V>, + map, + BTreeMap::new()); + +#[cfg(feature = "std")] +map_impl!( + HashMap<K: Eq + Hash, V, S: BuildHasher + Default>, + map, + HashMap::with_capacity_and_hasher(size_hint::cautious(map.size_hint()), S::default())); + +//////////////////////////////////////////////////////////////////////////////// + +#[cfg(feature = "std")] +macro_rules! parse_ip_impl { + ($expecting:tt $ty:ty; $size:tt) => { + impl<'de> Deserialize<'de> for $ty { + fn deserialize<D>(deserializer: D) -> Result<Self, D::Error> + where + D: Deserializer<'de>, + { + if deserializer.is_human_readable() { + deserializer.deserialize_str(FromStrVisitor::new($expecting)) + } else { + <[u8; $size]>::deserialize(deserializer).map(<$ty>::from) + } + } + } + }; +} + +#[cfg(feature = "std")] +macro_rules! variant_identifier { + ( + $name_kind:ident ($($variant:ident; $bytes:expr; $index:expr),*) + $expecting_message:expr, + $variants_name:ident + ) => { + enum $name_kind { + $($variant),* + } + + static $variants_name: &'static [&'static str] = &[$(stringify!($variant)),*]; + + impl<'de> Deserialize<'de> for $name_kind { + fn deserialize<D>(deserializer: D) -> Result<Self, D::Error> + where + D: Deserializer<'de>, + { + struct KindVisitor; + + impl<'de> Visitor<'de> for KindVisitor { + type Value = $name_kind; + + fn expecting(&self, formatter: &mut fmt::Formatter) -> fmt::Result { + formatter.write_str($expecting_message) + } + + fn visit_u64<E>(self, value: u64) -> Result<Self::Value, E> + where + E: Error, + { + match value { + $( + $index => Ok($name_kind :: $variant), + )* + _ => Err(Error::invalid_value(Unexpected::Unsigned(value), &self),), + } + } + + fn visit_str<E>(self, value: &str) -> Result<Self::Value, E> + where + E: Error, + { + match value { + $( + stringify!($variant) => Ok($name_kind :: $variant), + )* + _ => Err(Error::unknown_variant(value, $variants_name)), + } + } + + fn visit_bytes<E>(self, value: &[u8]) -> Result<Self::Value, E> + where + E: Error, + { + match value { + $( + $bytes => Ok($name_kind :: $variant), + )* + _ => { + match str::from_utf8(value) { + Ok(value) => Err(Error::unknown_variant(value, $variants_name)), + Err(_) => Err(Error::invalid_value(Unexpected::Bytes(value), &self)), + } + } + } + } + } + + deserializer.deserialize_identifier(KindVisitor) + } + } + } +} + +#[cfg(feature = "std")] +macro_rules! deserialize_enum { + ( + $name:ident $name_kind:ident ($($variant:ident; $bytes:expr; $index:expr),*) + $expecting_message:expr, + $deserializer:expr + ) => { + variant_identifier! { + $name_kind ($($variant; $bytes; $index),*) + $expecting_message, + VARIANTS + } + + struct EnumVisitor; + impl<'de> Visitor<'de> for EnumVisitor { + type Value = $name; + + fn expecting(&self, formatter: &mut fmt::Formatter) -> fmt::Result { + formatter.write_str(concat!("a ", stringify!($name))) + } + + + fn visit_enum<A>(self, data: A) -> Result<Self::Value, A::Error> + where + A: EnumAccess<'de>, + { + match try!(data.variant()) { + $( + ($name_kind :: $variant, v) => v.newtype_variant().map($name :: $variant), + )* + } + } + } + $deserializer.deserialize_enum(stringify!($name), VARIANTS, EnumVisitor) + } +} + +#[cfg(feature = "std")] +impl<'de> Deserialize<'de> for net::IpAddr { + fn deserialize<D>(deserializer: D) -> Result<Self, D::Error> + where + D: Deserializer<'de>, + { + if deserializer.is_human_readable() { + deserializer.deserialize_str(FromStrVisitor::new("IP address")) + } else { + use lib::net::IpAddr; + deserialize_enum! { + IpAddr IpAddrKind (V4; b"V4"; 0, V6; b"V6"; 1) + "`V4` or `V6`", + deserializer + } + } + } +} + +#[cfg(feature = "std")] +parse_ip_impl!("IPv4 address" net::Ipv4Addr; 4); + +#[cfg(feature = "std")] +parse_ip_impl!("IPv6 address" net::Ipv6Addr; 16); + +#[cfg(feature = "std")] +macro_rules! parse_socket_impl { + ($expecting:tt $ty:ty, $new:expr) => { + impl<'de> Deserialize<'de> for $ty { + fn deserialize<D>(deserializer: D) -> Result<Self, D::Error> + where + D: Deserializer<'de>, + { + if deserializer.is_human_readable() { + deserializer.deserialize_str(FromStrVisitor::new($expecting)) + } else { + <(_, u16)>::deserialize(deserializer).map(|(ip, port)| $new(ip, port)) + } + } + } + }; +} + +#[cfg(feature = "std")] +impl<'de> Deserialize<'de> for net::SocketAddr { + fn deserialize<D>(deserializer: D) -> Result<Self, D::Error> + where + D: Deserializer<'de>, + { + if deserializer.is_human_readable() { + deserializer.deserialize_str(FromStrVisitor::new("socket address")) + } else { + use lib::net::SocketAddr; + deserialize_enum! { + SocketAddr SocketAddrKind (V4; b"V4"; 0, V6; b"V6"; 1) + "`V4` or `V6`", + deserializer + } + } + } +} + +#[cfg(feature = "std")] +parse_socket_impl!("IPv4 socket address" net::SocketAddrV4, net::SocketAddrV4::new); + +#[cfg(feature = "std")] +parse_socket_impl!("IPv6 socket address" net::SocketAddrV6, |ip, port| net::SocketAddrV6::new( + ip, port, 0, 0 +)); + +//////////////////////////////////////////////////////////////////////////////// + +#[cfg(feature = "std")] +struct PathVisitor; + +#[cfg(feature = "std")] +impl<'a> Visitor<'a> for PathVisitor { + type Value = &'a Path; + + fn expecting(&self, formatter: &mut fmt::Formatter) -> fmt::Result { + formatter.write_str("a borrowed path") + } + + fn visit_borrowed_str<E>(self, v: &'a str) -> Result<Self::Value, E> + where + E: Error, + { + Ok(v.as_ref()) + } + + fn visit_borrowed_bytes<E>(self, v: &'a [u8]) -> Result<Self::Value, E> + where + E: Error, + { + str::from_utf8(v) + .map(AsRef::as_ref) + .map_err(|_| Error::invalid_value(Unexpected::Bytes(v), &self)) + } +} + +#[cfg(feature = "std")] +impl<'de: 'a, 'a> Deserialize<'de> for &'a Path { + fn deserialize<D>(deserializer: D) -> Result<Self, D::Error> + where + D: Deserializer<'de>, + { + deserializer.deserialize_str(PathVisitor) + } +} + +#[cfg(feature = "std")] +struct PathBufVisitor; + +#[cfg(feature = "std")] +impl<'de> Visitor<'de> for PathBufVisitor { + type Value = PathBuf; + + fn expecting(&self, formatter: &mut fmt::Formatter) -> fmt::Result { + formatter.write_str("path string") + } + + fn visit_str<E>(self, v: &str) -> Result<Self::Value, E> + where + E: Error, + { + Ok(From::from(v)) + } + + fn visit_string<E>(self, v: String) -> Result<Self::Value, E> + where + E: Error, + { + Ok(From::from(v)) + } + + fn visit_bytes<E>(self, v: &[u8]) -> Result<Self::Value, E> + where + E: Error, + { + str::from_utf8(v) + .map(From::from) + .map_err(|_| Error::invalid_value(Unexpected::Bytes(v), &self)) + } + + fn visit_byte_buf<E>(self, v: Vec<u8>) -> Result<Self::Value, E> + where + E: Error, + { + String::from_utf8(v) + .map(From::from) + .map_err(|e| Error::invalid_value(Unexpected::Bytes(&e.into_bytes()), &self)) + } +} + +#[cfg(feature = "std")] +impl<'de> Deserialize<'de> for PathBuf { + fn deserialize<D>(deserializer: D) -> Result<Self, D::Error> + where + D: Deserializer<'de>, + { + deserializer.deserialize_string(PathBufVisitor) + } +} + +#[cfg(all(feature = "std", not(no_de_boxed_path)))] +forwarded_impl!((), Box<Path>, PathBuf::into_boxed_path); + +//////////////////////////////////////////////////////////////////////////////// + +// If this were outside of the serde crate, it would just use: +// +// #[derive(Deserialize)] +// #[serde(variant_identifier)] +#[cfg(all(feature = "std", any(unix, windows)))] +variant_identifier! { + OsStringKind (Unix; b"Unix"; 0, Windows; b"Windows"; 1) + "`Unix` or `Windows`", + OSSTR_VARIANTS +} + +#[cfg(all(feature = "std", any(unix, windows)))] +struct OsStringVisitor; + +#[cfg(all(feature = "std", any(unix, windows)))] +impl<'de> Visitor<'de> for OsStringVisitor { + type Value = OsString; + + fn expecting(&self, formatter: &mut fmt::Formatter) -> fmt::Result { + formatter.write_str("os string") + } + + #[cfg(unix)] + fn visit_enum<A>(self, data: A) -> Result<Self::Value, A::Error> + where + A: EnumAccess<'de>, + { + use std::os::unix::ffi::OsStringExt; + + match try!(data.variant()) { + (OsStringKind::Unix, v) => v.newtype_variant().map(OsString::from_vec), + (OsStringKind::Windows, _) => Err(Error::custom( + "cannot deserialize Windows OS string on Unix", + )), + } + } + + #[cfg(windows)] + fn visit_enum<A>(self, data: A) -> Result<Self::Value, A::Error> + where + A: EnumAccess<'de>, + { + use std::os::windows::ffi::OsStringExt; + + match try!(data.variant()) { + (OsStringKind::Windows, v) => v + .newtype_variant::<Vec<u16>>() + .map(|vec| OsString::from_wide(&vec)), + (OsStringKind::Unix, _) => Err(Error::custom( + "cannot deserialize Unix OS string on Windows", + )), + } + } +} + +#[cfg(all(feature = "std", any(unix, windows)))] +impl<'de> Deserialize<'de> for OsString { + fn deserialize<D>(deserializer: D) -> Result<Self, D::Error> + where + D: Deserializer<'de>, + { + deserializer.deserialize_enum("OsString", OSSTR_VARIANTS, OsStringVisitor) + } +} + +//////////////////////////////////////////////////////////////////////////////// + +#[cfg(any(feature = "std", feature = "alloc"))] +forwarded_impl!((T), Box<T>, Box::new); + +#[cfg(any(feature = "std", feature = "alloc"))] +forwarded_impl!((T), Box<[T]>, Vec::into_boxed_slice); + +#[cfg(any(feature = "std", feature = "alloc"))] +forwarded_impl!((), Box<str>, String::into_boxed_str); + +#[cfg(all(no_de_rc_dst, feature = "rc", any(feature = "std", feature = "alloc")))] +forwarded_impl! { + /// This impl requires the [`"rc"`] Cargo feature of Serde. + /// + /// Deserializing a data structure containing `Arc` will not attempt to + /// deduplicate `Arc` references to the same data. Every deserialized `Arc` + /// will end up with a strong count of 1. + /// + /// [`"rc"`]: https://serde.rs/feature-flags.html#-features-rc + (T), Arc<T>, Arc::new +} + +#[cfg(all(no_de_rc_dst, feature = "rc", any(feature = "std", feature = "alloc")))] +forwarded_impl! { + /// This impl requires the [`"rc"`] Cargo feature of Serde. + /// + /// Deserializing a data structure containing `Rc` will not attempt to + /// deduplicate `Rc` references to the same data. Every deserialized `Rc` + /// will end up with a strong count of 1. + /// + /// [`"rc"`]: https://serde.rs/feature-flags.html#-features-rc + (T), Rc<T>, Rc::new +} + +#[cfg(any(feature = "std", feature = "alloc"))] +impl<'de, 'a, T: ?Sized> Deserialize<'de> for Cow<'a, T> +where + T: ToOwned, + T::Owned: Deserialize<'de>, +{ + #[inline] + fn deserialize<D>(deserializer: D) -> Result<Self, D::Error> + where + D: Deserializer<'de>, + { + T::Owned::deserialize(deserializer).map(Cow::Owned) + } +} + +//////////////////////////////////////////////////////////////////////////////// + +/// This impl requires the [`"rc"`] Cargo feature of Serde. The resulting +/// `Weak<T>` has a reference count of 0 and cannot be upgraded. +/// +/// [`"rc"`]: https://serde.rs/feature-flags.html#-features-rc +#[cfg(all(feature = "rc", any(feature = "std", feature = "alloc")))] +impl<'de, T: ?Sized> Deserialize<'de> for RcWeak<T> +where + T: Deserialize<'de>, +{ + fn deserialize<D>(deserializer: D) -> Result<Self, D::Error> + where + D: Deserializer<'de>, + { + try!(Option::<T>::deserialize(deserializer)); + Ok(RcWeak::new()) + } +} + +/// This impl requires the [`"rc"`] Cargo feature of Serde. The resulting +/// `Weak<T>` has a reference count of 0 and cannot be upgraded. +/// +/// [`"rc"`]: https://serde.rs/feature-flags.html#-features-rc +#[cfg(all(feature = "rc", any(feature = "std", feature = "alloc")))] +impl<'de, T: ?Sized> Deserialize<'de> for ArcWeak<T> +where + T: Deserialize<'de>, +{ + fn deserialize<D>(deserializer: D) -> Result<Self, D::Error> + where + D: Deserializer<'de>, + { + try!(Option::<T>::deserialize(deserializer)); + Ok(ArcWeak::new()) + } +} + +//////////////////////////////////////////////////////////////////////////////// + +#[cfg(all( + not(no_de_rc_dst), + feature = "rc", + any(feature = "std", feature = "alloc") +))] +macro_rules! box_forwarded_impl { + ( + $(#[doc = $doc:tt])* + $t:ident + ) => { + $(#[doc = $doc])* + impl<'de, T: ?Sized> Deserialize<'de> for $t<T> + where + Box<T>: Deserialize<'de>, + { + fn deserialize<D>(deserializer: D) -> Result<Self, D::Error> + where + D: Deserializer<'de>, + { + Box::deserialize(deserializer).map(Into::into) + } + } + }; +} + +#[cfg(all( + not(no_de_rc_dst), + feature = "rc", + any(feature = "std", feature = "alloc") +))] +box_forwarded_impl! { + /// This impl requires the [`"rc"`] Cargo feature of Serde. + /// + /// Deserializing a data structure containing `Rc` will not attempt to + /// deduplicate `Rc` references to the same data. Every deserialized `Rc` + /// will end up with a strong count of 1. + /// + /// [`"rc"`]: https://serde.rs/feature-flags.html#-features-rc + Rc +} + +#[cfg(all( + not(no_de_rc_dst), + feature = "rc", + any(feature = "std", feature = "alloc") +))] +box_forwarded_impl! { + /// This impl requires the [`"rc"`] Cargo feature of Serde. + /// + /// Deserializing a data structure containing `Arc` will not attempt to + /// deduplicate `Arc` references to the same data. Every deserialized `Arc` + /// will end up with a strong count of 1. + /// + /// [`"rc"`]: https://serde.rs/feature-flags.html#-features-rc + Arc +} + +//////////////////////////////////////////////////////////////////////////////// + +impl<'de, T> Deserialize<'de> for Cell<T> +where + T: Deserialize<'de> + Copy, +{ + fn deserialize<D>(deserializer: D) -> Result<Self, D::Error> + where + D: Deserializer<'de>, + { + T::deserialize(deserializer).map(Cell::new) + } +} + +forwarded_impl!((T), RefCell<T>, RefCell::new); + +#[cfg(feature = "std")] +forwarded_impl!((T), Mutex<T>, Mutex::new); + +#[cfg(feature = "std")] +forwarded_impl!((T), RwLock<T>, RwLock::new); + +//////////////////////////////////////////////////////////////////////////////// + +// This is a cleaned-up version of the impl generated by: +// +// #[derive(Deserialize)] +// #[serde(deny_unknown_fields)] +// struct Duration { +// secs: u64, +// nanos: u32, +// } +#[cfg(any(feature = "std", not(no_core_duration)))] +impl<'de> Deserialize<'de> for Duration { + fn deserialize<D>(deserializer: D) -> Result<Self, D::Error> + where + D: Deserializer<'de>, + { + // If this were outside of the serde crate, it would just use: + // + // #[derive(Deserialize)] + // #[serde(field_identifier, rename_all = "lowercase")] + enum Field { + Secs, + Nanos, + } + + impl<'de> Deserialize<'de> for Field { + fn deserialize<D>(deserializer: D) -> Result<Self, D::Error> + where + D: Deserializer<'de>, + { + struct FieldVisitor; + + impl<'de> Visitor<'de> for FieldVisitor { + type Value = Field; + + fn expecting(&self, formatter: &mut fmt::Formatter) -> fmt::Result { + formatter.write_str("`secs` or `nanos`") + } + + fn visit_str<E>(self, value: &str) -> Result<Self::Value, E> + where + E: Error, + { + match value { + "secs" => Ok(Field::Secs), + "nanos" => Ok(Field::Nanos), + _ => Err(Error::unknown_field(value, FIELDS)), + } + } + + fn visit_bytes<E>(self, value: &[u8]) -> Result<Self::Value, E> + where + E: Error, + { + match value { + b"secs" => Ok(Field::Secs), + b"nanos" => Ok(Field::Nanos), + _ => { + let value = ::__private::from_utf8_lossy(value); + Err(Error::unknown_field(&*value, FIELDS)) + } + } + } + } + + deserializer.deserialize_identifier(FieldVisitor) + } + } + + fn check_overflow<E>(secs: u64, nanos: u32) -> Result<(), E> + where + E: Error, + { + static NANOS_PER_SEC: u32 = 1_000_000_000; + match secs.checked_add((nanos / NANOS_PER_SEC) as u64) { + Some(_) => Ok(()), + None => Err(E::custom("overflow deserializing Duration")), + } + } + + struct DurationVisitor; + + impl<'de> Visitor<'de> for DurationVisitor { + type Value = Duration; + + fn expecting(&self, formatter: &mut fmt::Formatter) -> fmt::Result { + formatter.write_str("struct Duration") + } + + fn visit_seq<A>(self, mut seq: A) -> Result<Self::Value, A::Error> + where + A: SeqAccess<'de>, + { + let secs: u64 = match try!(seq.next_element()) { + Some(value) => value, + None => { + return Err(Error::invalid_length(0, &self)); + } + }; + let nanos: u32 = match try!(seq.next_element()) { + Some(value) => value, + None => { + return Err(Error::invalid_length(1, &self)); + } + }; + try!(check_overflow(secs, nanos)); + Ok(Duration::new(secs, nanos)) + } + + fn visit_map<A>(self, mut map: A) -> Result<Self::Value, A::Error> + where + A: MapAccess<'de>, + { + let mut secs: Option<u64> = None; + let mut nanos: Option<u32> = None; + while let Some(key) = try!(map.next_key()) { + match key { + Field::Secs => { + if secs.is_some() { + return Err(<A::Error as Error>::duplicate_field("secs")); + } + secs = Some(try!(map.next_value())); + } + Field::Nanos => { + if nanos.is_some() { + return Err(<A::Error as Error>::duplicate_field("nanos")); + } + nanos = Some(try!(map.next_value())); + } + } + } + let secs = match secs { + Some(secs) => secs, + None => return Err(<A::Error as Error>::missing_field("secs")), + }; + let nanos = match nanos { + Some(nanos) => nanos, + None => return Err(<A::Error as Error>::missing_field("nanos")), + }; + try!(check_overflow(secs, nanos)); + Ok(Duration::new(secs, nanos)) + } + } + + const FIELDS: &'static [&'static str] = &["secs", "nanos"]; + deserializer.deserialize_struct("Duration", FIELDS, DurationVisitor) + } +} + +//////////////////////////////////////////////////////////////////////////////// + +#[cfg(feature = "std")] +impl<'de> Deserialize<'de> for SystemTime { + fn deserialize<D>(deserializer: D) -> Result<Self, D::Error> + where + D: Deserializer<'de>, + { + // Reuse duration + enum Field { + Secs, + Nanos, + } + + impl<'de> Deserialize<'de> for Field { + fn deserialize<D>(deserializer: D) -> Result<Self, D::Error> + where + D: Deserializer<'de>, + { + struct FieldVisitor; + + impl<'de> Visitor<'de> for FieldVisitor { + type Value = Field; + + fn expecting(&self, formatter: &mut fmt::Formatter) -> fmt::Result { + formatter.write_str("`secs_since_epoch` or `nanos_since_epoch`") + } + + fn visit_str<E>(self, value: &str) -> Result<Self::Value, E> + where + E: Error, + { + match value { + "secs_since_epoch" => Ok(Field::Secs), + "nanos_since_epoch" => Ok(Field::Nanos), + _ => Err(Error::unknown_field(value, FIELDS)), + } + } + + fn visit_bytes<E>(self, value: &[u8]) -> Result<Self::Value, E> + where + E: Error, + { + match value { + b"secs_since_epoch" => Ok(Field::Secs), + b"nanos_since_epoch" => Ok(Field::Nanos), + _ => { + let value = String::from_utf8_lossy(value); + Err(Error::unknown_field(&value, FIELDS)) + } + } + } + } + + deserializer.deserialize_identifier(FieldVisitor) + } + } + + fn check_overflow<E>(secs: u64, nanos: u32) -> Result<(), E> + where + E: Error, + { + static NANOS_PER_SEC: u32 = 1_000_000_000; + match secs.checked_add((nanos / NANOS_PER_SEC) as u64) { + Some(_) => Ok(()), + None => Err(E::custom("overflow deserializing SystemTime epoch offset")), + } + } + + struct DurationVisitor; + + impl<'de> Visitor<'de> for DurationVisitor { + type Value = Duration; + + fn expecting(&self, formatter: &mut fmt::Formatter) -> fmt::Result { + formatter.write_str("struct SystemTime") + } + + fn visit_seq<A>(self, mut seq: A) -> Result<Self::Value, A::Error> + where + A: SeqAccess<'de>, + { + let secs: u64 = match try!(seq.next_element()) { + Some(value) => value, + None => { + return Err(Error::invalid_length(0, &self)); + } + }; + let nanos: u32 = match try!(seq.next_element()) { + Some(value) => value, + None => { + return Err(Error::invalid_length(1, &self)); + } + }; + try!(check_overflow(secs, nanos)); + Ok(Duration::new(secs, nanos)) + } + + fn visit_map<A>(self, mut map: A) -> Result<Self::Value, A::Error> + where + A: MapAccess<'de>, + { + let mut secs: Option<u64> = None; + let mut nanos: Option<u32> = None; + while let Some(key) = try!(map.next_key()) { + match key { + Field::Secs => { + if secs.is_some() { + return Err(<A::Error as Error>::duplicate_field( + "secs_since_epoch", + )); + } + secs = Some(try!(map.next_value())); + } + Field::Nanos => { + if nanos.is_some() { + return Err(<A::Error as Error>::duplicate_field( + "nanos_since_epoch", + )); + } + nanos = Some(try!(map.next_value())); + } + } + } + let secs = match secs { + Some(secs) => secs, + None => return Err(<A::Error as Error>::missing_field("secs_since_epoch")), + }; + let nanos = match nanos { + Some(nanos) => nanos, + None => return Err(<A::Error as Error>::missing_field("nanos_since_epoch")), + }; + try!(check_overflow(secs, nanos)); + Ok(Duration::new(secs, nanos)) + } + } + + const FIELDS: &'static [&'static str] = &["secs_since_epoch", "nanos_since_epoch"]; + let duration = try!(deserializer.deserialize_struct("SystemTime", FIELDS, DurationVisitor)); + #[cfg(not(no_systemtime_checked_add))] + let ret = UNIX_EPOCH + .checked_add(duration) + .ok_or_else(|| D::Error::custom("overflow deserializing SystemTime")); + #[cfg(no_systemtime_checked_add)] + let ret = Ok(UNIX_EPOCH + duration); + ret + } +} + +//////////////////////////////////////////////////////////////////////////////// + +// Similar to: +// +// #[derive(Deserialize)] +// #[serde(deny_unknown_fields)] +// struct Range { +// start: u64, +// end: u32, +// } +impl<'de, Idx> Deserialize<'de> for Range<Idx> +where + Idx: Deserialize<'de>, +{ + fn deserialize<D>(deserializer: D) -> Result<Self, D::Error> + where + D: Deserializer<'de>, + { + let (start, end) = try!(deserializer.deserialize_struct( + "Range", + range::FIELDS, + range::RangeVisitor { + expecting: "struct Range", + phantom: PhantomData, + }, + )); + Ok(start..end) + } +} + +#[cfg(not(no_range_inclusive))] +impl<'de, Idx> Deserialize<'de> for RangeInclusive<Idx> +where + Idx: Deserialize<'de>, +{ + fn deserialize<D>(deserializer: D) -> Result<Self, D::Error> + where + D: Deserializer<'de>, + { + let (start, end) = try!(deserializer.deserialize_struct( + "RangeInclusive", + range::FIELDS, + range::RangeVisitor { + expecting: "struct RangeInclusive", + phantom: PhantomData, + }, + )); + Ok(RangeInclusive::new(start, end)) + } +} + +mod range { + use lib::*; + + use de::{Deserialize, Deserializer, Error, MapAccess, SeqAccess, Visitor}; + + pub const FIELDS: &'static [&'static str] = &["start", "end"]; + + // If this were outside of the serde crate, it would just use: + // + // #[derive(Deserialize)] + // #[serde(field_identifier, rename_all = "lowercase")] + enum Field { + Start, + End, + } + + impl<'de> Deserialize<'de> for Field { + fn deserialize<D>(deserializer: D) -> Result<Self, D::Error> + where + D: Deserializer<'de>, + { + struct FieldVisitor; + + impl<'de> Visitor<'de> for FieldVisitor { + type Value = Field; + + fn expecting(&self, formatter: &mut fmt::Formatter) -> fmt::Result { + formatter.write_str("`start` or `end`") + } + + fn visit_str<E>(self, value: &str) -> Result<Self::Value, E> + where + E: Error, + { + match value { + "start" => Ok(Field::Start), + "end" => Ok(Field::End), + _ => Err(Error::unknown_field(value, FIELDS)), + } + } + + fn visit_bytes<E>(self, value: &[u8]) -> Result<Self::Value, E> + where + E: Error, + { + match value { + b"start" => Ok(Field::Start), + b"end" => Ok(Field::End), + _ => { + let value = ::__private::from_utf8_lossy(value); + Err(Error::unknown_field(&*value, FIELDS)) + } + } + } + } + + deserializer.deserialize_identifier(FieldVisitor) + } + } + + pub struct RangeVisitor<Idx> { + pub expecting: &'static str, + pub phantom: PhantomData<Idx>, + } + + impl<'de, Idx> Visitor<'de> for RangeVisitor<Idx> + where + Idx: Deserialize<'de>, + { + type Value = (Idx, Idx); + + fn expecting(&self, formatter: &mut fmt::Formatter) -> fmt::Result { + formatter.write_str(self.expecting) + } + + fn visit_seq<A>(self, mut seq: A) -> Result<Self::Value, A::Error> + where + A: SeqAccess<'de>, + { + let start: Idx = match try!(seq.next_element()) { + Some(value) => value, + None => { + return Err(Error::invalid_length(0, &self)); + } + }; + let end: Idx = match try!(seq.next_element()) { + Some(value) => value, + None => { + return Err(Error::invalid_length(1, &self)); + } + }; + Ok((start, end)) + } + + fn visit_map<A>(self, mut map: A) -> Result<Self::Value, A::Error> + where + A: MapAccess<'de>, + { + let mut start: Option<Idx> = None; + let mut end: Option<Idx> = None; + while let Some(key) = try!(map.next_key()) { + match key { + Field::Start => { + if start.is_some() { + return Err(<A::Error as Error>::duplicate_field("start")); + } + start = Some(try!(map.next_value())); + } + Field::End => { + if end.is_some() { + return Err(<A::Error as Error>::duplicate_field("end")); + } + end = Some(try!(map.next_value())); + } + } + } + let start = match start { + Some(start) => start, + None => return Err(<A::Error as Error>::missing_field("start")), + }; + let end = match end { + Some(end) => end, + None => return Err(<A::Error as Error>::missing_field("end")), + }; + Ok((start, end)) + } + } +} + +//////////////////////////////////////////////////////////////////////////////// + +#[cfg(any(not(no_ops_bound), all(feature = "std", not(no_collections_bound))))] +impl<'de, T> Deserialize<'de> for Bound<T> +where + T: Deserialize<'de>, +{ + fn deserialize<D>(deserializer: D) -> Result<Self, D::Error> + where + D: Deserializer<'de>, + { + enum Field { + Unbounded, + Included, + Excluded, + } + + impl<'de> Deserialize<'de> for Field { + #[inline] + fn deserialize<D>(deserializer: D) -> Result<Self, D::Error> + where + D: Deserializer<'de>, + { + struct FieldVisitor; + + impl<'de> Visitor<'de> for FieldVisitor { + type Value = Field; + + fn expecting(&self, formatter: &mut fmt::Formatter) -> fmt::Result { + formatter.write_str("`Unbounded`, `Included` or `Excluded`") + } + + fn visit_u64<E>(self, value: u64) -> Result<Self::Value, E> + where + E: Error, + { + match value { + 0 => Ok(Field::Unbounded), + 1 => Ok(Field::Included), + 2 => Ok(Field::Excluded), + _ => Err(Error::invalid_value(Unexpected::Unsigned(value), &self)), + } + } + + fn visit_str<E>(self, value: &str) -> Result<Self::Value, E> + where + E: Error, + { + match value { + "Unbounded" => Ok(Field::Unbounded), + "Included" => Ok(Field::Included), + "Excluded" => Ok(Field::Excluded), + _ => Err(Error::unknown_variant(value, VARIANTS)), + } + } + + fn visit_bytes<E>(self, value: &[u8]) -> Result<Self::Value, E> + where + E: Error, + { + match value { + b"Unbounded" => Ok(Field::Unbounded), + b"Included" => Ok(Field::Included), + b"Excluded" => Ok(Field::Excluded), + _ => match str::from_utf8(value) { + Ok(value) => Err(Error::unknown_variant(value, VARIANTS)), + Err(_) => { + Err(Error::invalid_value(Unexpected::Bytes(value), &self)) + } + }, + } + } + } + + deserializer.deserialize_identifier(FieldVisitor) + } + } + + struct BoundVisitor<T>(PhantomData<Bound<T>>); + + impl<'de, T> Visitor<'de> for BoundVisitor<T> + where + T: Deserialize<'de>, + { + type Value = Bound<T>; + + fn expecting(&self, formatter: &mut fmt::Formatter) -> fmt::Result { + formatter.write_str("enum Bound") + } + + fn visit_enum<A>(self, data: A) -> Result<Self::Value, A::Error> + where + A: EnumAccess<'de>, + { + match try!(data.variant()) { + (Field::Unbounded, v) => v.unit_variant().map(|()| Bound::Unbounded), + (Field::Included, v) => v.newtype_variant().map(Bound::Included), + (Field::Excluded, v) => v.newtype_variant().map(Bound::Excluded), + } + } + } + + const VARIANTS: &'static [&'static str] = &["Unbounded", "Included", "Excluded"]; + + deserializer.deserialize_enum("Bound", VARIANTS, BoundVisitor(PhantomData)) + } +} + +//////////////////////////////////////////////////////////////////////////////// + +impl<'de, T, E> Deserialize<'de> for Result<T, E> +where + T: Deserialize<'de>, + E: Deserialize<'de>, +{ + fn deserialize<D>(deserializer: D) -> Result<Self, D::Error> + where + D: Deserializer<'de>, + { + // If this were outside of the serde crate, it would just use: + // + // #[derive(Deserialize)] + // #[serde(variant_identifier)] + enum Field { + Ok, + Err, + } + + impl<'de> Deserialize<'de> for Field { + #[inline] + fn deserialize<D>(deserializer: D) -> Result<Self, D::Error> + where + D: Deserializer<'de>, + { + struct FieldVisitor; + + impl<'de> Visitor<'de> for FieldVisitor { + type Value = Field; + + fn expecting(&self, formatter: &mut fmt::Formatter) -> fmt::Result { + formatter.write_str("`Ok` or `Err`") + } + + fn visit_u64<E>(self, value: u64) -> Result<Self::Value, E> + where + E: Error, + { + match value { + 0 => Ok(Field::Ok), + 1 => Ok(Field::Err), + _ => Err(Error::invalid_value(Unexpected::Unsigned(value), &self)), + } + } + + fn visit_str<E>(self, value: &str) -> Result<Self::Value, E> + where + E: Error, + { + match value { + "Ok" => Ok(Field::Ok), + "Err" => Ok(Field::Err), + _ => Err(Error::unknown_variant(value, VARIANTS)), + } + } + + fn visit_bytes<E>(self, value: &[u8]) -> Result<Self::Value, E> + where + E: Error, + { + match value { + b"Ok" => Ok(Field::Ok), + b"Err" => Ok(Field::Err), + _ => match str::from_utf8(value) { + Ok(value) => Err(Error::unknown_variant(value, VARIANTS)), + Err(_) => { + Err(Error::invalid_value(Unexpected::Bytes(value), &self)) + } + }, + } + } + } + + deserializer.deserialize_identifier(FieldVisitor) + } + } + + struct ResultVisitor<T, E>(PhantomData<Result<T, E>>); + + impl<'de, T, E> Visitor<'de> for ResultVisitor<T, E> + where + T: Deserialize<'de>, + E: Deserialize<'de>, + { + type Value = Result<T, E>; + + fn expecting(&self, formatter: &mut fmt::Formatter) -> fmt::Result { + formatter.write_str("enum Result") + } + + fn visit_enum<A>(self, data: A) -> Result<Self::Value, A::Error> + where + A: EnumAccess<'de>, + { + match try!(data.variant()) { + (Field::Ok, v) => v.newtype_variant().map(Ok), + (Field::Err, v) => v.newtype_variant().map(Err), + } + } + } + + const VARIANTS: &'static [&'static str] = &["Ok", "Err"]; + + deserializer.deserialize_enum("Result", VARIANTS, ResultVisitor(PhantomData)) + } +} + +//////////////////////////////////////////////////////////////////////////////// + +impl<'de, T> Deserialize<'de> for Wrapping<T> +where + T: Deserialize<'de>, +{ + fn deserialize<D>(deserializer: D) -> Result<Self, D::Error> + where + D: Deserializer<'de>, + { + Deserialize::deserialize(deserializer).map(Wrapping) + } +} + +#[cfg(all(feature = "std", not(no_std_atomic)))] +macro_rules! atomic_impl { + ($($ty:ident $size:expr)*) => { + $( + #[cfg(any(no_target_has_atomic, target_has_atomic = $size))] + impl<'de> Deserialize<'de> for $ty { + fn deserialize<D>(deserializer: D) -> Result<Self, D::Error> + where + D: Deserializer<'de>, + { + Deserialize::deserialize(deserializer).map(Self::new) + } + } + )* + }; +} + +#[cfg(all(feature = "std", not(no_std_atomic)))] +atomic_impl! { + AtomicBool "8" + AtomicI8 "8" + AtomicI16 "16" + AtomicI32 "32" + AtomicIsize "ptr" + AtomicU8 "8" + AtomicU16 "16" + AtomicU32 "32" + AtomicUsize "ptr" +} + +#[cfg(all(feature = "std", not(no_std_atomic64)))] +atomic_impl! { + AtomicI64 "64" + AtomicU64 "64" +} + +#[cfg(feature = "std")] +struct FromStrVisitor<T> { + expecting: &'static str, + ty: PhantomData<T>, +} + +#[cfg(feature = "std")] +impl<T> FromStrVisitor<T> { + fn new(expecting: &'static str) -> Self { + FromStrVisitor { + expecting: expecting, + ty: PhantomData, + } + } +} + +#[cfg(feature = "std")] +impl<'de, T> Visitor<'de> for FromStrVisitor<T> +where + T: str::FromStr, + T::Err: fmt::Display, +{ + type Value = T; + + fn expecting(&self, formatter: &mut fmt::Formatter) -> fmt::Result { + formatter.write_str(self.expecting) + } + + fn visit_str<E>(self, s: &str) -> Result<Self::Value, E> + where + E: Error, + { + s.parse().map_err(Error::custom) + } +} diff --git a/src/de/mod.rs b/src/de/mod.rs new file mode 100644 index 0000000..ca29ec6 --- /dev/null +++ b/src/de/mod.rs @@ -0,0 +1,2299 @@ +//! Generic data structure deserialization framework. +//! +//! The two most important traits in this module are [`Deserialize`] and +//! [`Deserializer`]. +//! +//! - **A type that implements `Deserialize` is a data structure** that can be +//! deserialized from any data format supported by Serde, and conversely +//! - **A type that implements `Deserializer` is a data format** that can +//! deserialize any data structure supported by Serde. +//! +//! # The Deserialize trait +//! +//! Serde provides [`Deserialize`] implementations for many Rust primitive and +//! standard library types. The complete list is below. All of these can be +//! deserialized using Serde out of the box. +//! +//! Additionally, Serde provides a procedural macro called [`serde_derive`] to +//! automatically generate [`Deserialize`] implementations for structs and enums +//! in your program. See the [derive section of the manual] for how to use this. +//! +//! In rare cases it may be necessary to implement [`Deserialize`] manually for +//! some type in your program. See the [Implementing `Deserialize`] section of +//! the manual for more about this. +//! +//! Third-party crates may provide [`Deserialize`] implementations for types +//! that they expose. For example the [`linked-hash-map`] crate provides a +//! [`LinkedHashMap<K, V>`] type that is deserializable by Serde because the +//! crate provides an implementation of [`Deserialize`] for it. +//! +//! # The Deserializer trait +//! +//! [`Deserializer`] implementations are provided by third-party crates, for +//! example [`serde_json`], [`serde_yaml`] and [`postcard`]. +//! +//! A partial list of well-maintained formats is given on the [Serde +//! website][data formats]. +//! +//! # Implementations of Deserialize provided by Serde +//! +//! This is a slightly different set of types than what is supported for +//! serialization. Some types can be serialized by Serde but not deserialized. +//! One example is `OsStr`. +//! +//! - **Primitive types**: +//! - bool +//! - i8, i16, i32, i64, i128, isize +//! - u8, u16, u32, u64, u128, usize +//! - f32, f64 +//! - char +//! - **Compound types**: +//! - \[T; 0\] through \[T; 32\] +//! - tuples up to size 16 +//! - **Common standard library types**: +//! - String +//! - Option\<T\> +//! - Result\<T, E\> +//! - PhantomData\<T\> +//! - **Wrapper types**: +//! - Box\<T\> +//! - Box\<\[T\]\> +//! - Box\<str\> +//! - Cow\<'a, T\> +//! - Cell\<T\> +//! - RefCell\<T\> +//! - Mutex\<T\> +//! - RwLock\<T\> +//! - Rc\<T\> *(if* features = ["rc"] *is enabled)* +//! - Arc\<T\> *(if* features = ["rc"] *is enabled)* +//! - **Collection types**: +//! - BTreeMap\<K, V\> +//! - BTreeSet\<T\> +//! - BinaryHeap\<T\> +//! - HashMap\<K, V, H\> +//! - HashSet\<T, H\> +//! - LinkedList\<T\> +//! - VecDeque\<T\> +//! - Vec\<T\> +//! - **Zero-copy types**: +//! - &str +//! - &\[u8\] +//! - **FFI types**: +//! - CString +//! - Box\<CStr\> +//! - OsString +//! - **Miscellaneous standard library types**: +//! - Duration +//! - SystemTime +//! - Path +//! - PathBuf +//! - Range\<T\> +//! - RangeInclusive\<T\> +//! - Bound\<T\> +//! - num::NonZero* +//! - `!` *(unstable)* +//! - **Net types**: +//! - IpAddr +//! - Ipv4Addr +//! - Ipv6Addr +//! - SocketAddr +//! - SocketAddrV4 +//! - SocketAddrV6 +//! +//! [Implementing `Deserialize`]: https://serde.rs/impl-deserialize.html +//! [`Deserialize`]: ../trait.Deserialize.html +//! [`Deserializer`]: ../trait.Deserializer.html +//! [`LinkedHashMap<K, V>`]: https://docs.rs/linked-hash-map/*/linked_hash_map/struct.LinkedHashMap.html +//! [`postcard`]: https://github.com/jamesmunns/postcard +//! [`linked-hash-map`]: https://crates.io/crates/linked-hash-map +//! [`serde_derive`]: https://crates.io/crates/serde_derive +//! [`serde_json`]: https://github.com/serde-rs/json +//! [`serde_yaml`]: https://github.com/dtolnay/serde-yaml +//! [derive section of the manual]: https://serde.rs/derive.html +//! [data formats]: https://serde.rs/#data-formats + +use lib::*; + +//////////////////////////////////////////////////////////////////////////////// + +pub mod value; + +#[cfg(not(no_integer128))] +mod format; +mod ignored_any; +mod impls; +mod utf8; + +pub use self::ignored_any::IgnoredAny; + +#[cfg(feature = "std")] +#[doc(no_inline)] +pub use std::error::Error as StdError; +#[cfg(not(feature = "std"))] +#[doc(no_inline)] +pub use std_error::Error as StdError; + +//////////////////////////////////////////////////////////////////////////////// + +macro_rules! declare_error_trait { + (Error: Sized $(+ $($supertrait:ident)::+)*) => { + /// The `Error` trait allows `Deserialize` implementations to create descriptive + /// error messages belonging to the `Deserializer` against which they are + /// currently running. + /// + /// Every `Deserializer` declares an `Error` type that encompasses both + /// general-purpose deserialization errors as well as errors specific to the + /// particular deserialization format. For example the `Error` type of + /// `serde_json` can represent errors like an invalid JSON escape sequence or an + /// unterminated string literal, in addition to the error cases that are part of + /// this trait. + /// + /// Most deserializers should only need to provide the `Error::custom` method + /// and inherit the default behavior for the other methods. + /// + /// # Example implementation + /// + /// The [example data format] presented on the website shows an error + /// type appropriate for a basic JSON data format. + /// + /// [example data format]: https://serde.rs/data-format.html + pub trait Error: Sized $(+ $($supertrait)::+)* { + /// Raised when there is general error when deserializing a type. + /// + /// The message should not be capitalized and should not end with a period. + /// + /// ```edition2018 + /// # use std::str::FromStr; + /// # + /// # struct IpAddr; + /// # + /// # impl FromStr for IpAddr { + /// # type Err = String; + /// # + /// # fn from_str(_: &str) -> Result<Self, String> { + /// # unimplemented!() + /// # } + /// # } + /// # + /// use serde::de::{self, Deserialize, Deserializer}; + /// + /// impl<'de> Deserialize<'de> for IpAddr { + /// fn deserialize<D>(deserializer: D) -> Result<Self, D::Error> + /// where + /// D: Deserializer<'de>, + /// { + /// let s = String::deserialize(deserializer)?; + /// s.parse().map_err(de::Error::custom) + /// } + /// } + /// ``` + fn custom<T>(msg: T) -> Self + where + T: Display; + + /// Raised when a `Deserialize` receives a type different from what it was + /// expecting. + /// + /// The `unexp` argument provides information about what type was received. + /// This is the type that was present in the input file or other source data + /// of the Deserializer. + /// + /// The `exp` argument provides information about what type was being + /// expected. This is the type that is written in the program. + /// + /// For example if we try to deserialize a String out of a JSON file + /// containing an integer, the unexpected type is the integer and the + /// expected type is the string. + #[cold] + fn invalid_type(unexp: Unexpected, exp: &Expected) -> Self { + Error::custom(format_args!("invalid type: {}, expected {}", unexp, exp)) + } + + /// Raised when a `Deserialize` receives a value of the right type but that + /// is wrong for some other reason. + /// + /// The `unexp` argument provides information about what value was received. + /// This is the value that was present in the input file or other source + /// data of the Deserializer. + /// + /// The `exp` argument provides information about what value was being + /// expected. This is the type that is written in the program. + /// + /// For example if we try to deserialize a String out of some binary data + /// that is not valid UTF-8, the unexpected value is the bytes and the + /// expected value is a string. + #[cold] + fn invalid_value(unexp: Unexpected, exp: &Expected) -> Self { + Error::custom(format_args!("invalid value: {}, expected {}", unexp, exp)) + } + + /// Raised when deserializing a sequence or map and the input data contains + /// too many or too few elements. + /// + /// The `len` argument is the number of elements encountered. The sequence + /// or map may have expected more arguments or fewer arguments. + /// + /// The `exp` argument provides information about what data was being + /// expected. For example `exp` might say that a tuple of size 6 was + /// expected. + #[cold] + fn invalid_length(len: usize, exp: &Expected) -> Self { + Error::custom(format_args!("invalid length {}, expected {}", len, exp)) + } + + /// Raised when a `Deserialize` enum type received a variant with an + /// unrecognized name. + #[cold] + fn unknown_variant(variant: &str, expected: &'static [&'static str]) -> Self { + if expected.is_empty() { + Error::custom(format_args!( + "unknown variant `{}`, there are no variants", + variant + )) + } else { + Error::custom(format_args!( + "unknown variant `{}`, expected {}", + variant, + OneOf { names: expected } + )) + } + } + + /// Raised when a `Deserialize` struct type received a field with an + /// unrecognized name. + #[cold] + fn unknown_field(field: &str, expected: &'static [&'static str]) -> Self { + if expected.is_empty() { + Error::custom(format_args!( + "unknown field `{}`, there are no fields", + field + )) + } else { + Error::custom(format_args!( + "unknown field `{}`, expected {}", + field, + OneOf { names: expected } + )) + } + } + + /// Raised when a `Deserialize` struct type expected to receive a required + /// field with a particular name but that field was not present in the + /// input. + #[cold] + fn missing_field(field: &'static str) -> Self { + Error::custom(format_args!("missing field `{}`", field)) + } + + /// Raised when a `Deserialize` struct type received more than one of the + /// same field. + #[cold] + fn duplicate_field(field: &'static str) -> Self { + Error::custom(format_args!("duplicate field `{}`", field)) + } + } + } +} + +#[cfg(feature = "std")] +declare_error_trait!(Error: Sized + StdError); + +#[cfg(not(feature = "std"))] +declare_error_trait!(Error: Sized + Debug + Display); + +/// `Unexpected` represents an unexpected invocation of any one of the `Visitor` +/// trait methods. +/// +/// This is used as an argument to the `invalid_type`, `invalid_value`, and +/// `invalid_length` methods of the `Error` trait to build error messages. +/// +/// ```edition2018 +/// # use std::fmt; +/// # +/// # use serde::de::{self, Unexpected, Visitor}; +/// # +/// # struct Example; +/// # +/// # impl<'de> Visitor<'de> for Example { +/// # type Value = (); +/// # +/// # fn expecting(&self, formatter: &mut fmt::Formatter) -> fmt::Result { +/// # write!(formatter, "definitely not a boolean") +/// # } +/// # +/// fn visit_bool<E>(self, v: bool) -> Result<Self::Value, E> +/// where +/// E: de::Error, +/// { +/// Err(de::Error::invalid_type(Unexpected::Bool(v), &self)) +/// } +/// # } +/// ``` +#[derive(Copy, Clone, PartialEq, Debug)] +pub enum Unexpected<'a> { + /// The input contained a boolean value that was not expected. + Bool(bool), + + /// The input contained an unsigned integer `u8`, `u16`, `u32` or `u64` that + /// was not expected. + Unsigned(u64), + + /// The input contained a signed integer `i8`, `i16`, `i32` or `i64` that + /// was not expected. + Signed(i64), + + /// The input contained a floating point `f32` or `f64` that was not + /// expected. + Float(f64), + + /// The input contained a `char` that was not expected. + Char(char), + + /// The input contained a `&str` or `String` that was not expected. + Str(&'a str), + + /// The input contained a `&[u8]` or `Vec<u8>` that was not expected. + Bytes(&'a [u8]), + + /// The input contained a unit `()` that was not expected. + Unit, + + /// The input contained an `Option<T>` that was not expected. + Option, + + /// The input contained a newtype struct that was not expected. + NewtypeStruct, + + /// The input contained a sequence that was not expected. + Seq, + + /// The input contained a map that was not expected. + Map, + + /// The input contained an enum that was not expected. + Enum, + + /// The input contained a unit variant that was not expected. + UnitVariant, + + /// The input contained a newtype variant that was not expected. + NewtypeVariant, + + /// The input contained a tuple variant that was not expected. + TupleVariant, + + /// The input contained a struct variant that was not expected. + StructVariant, + + /// A message stating what uncategorized thing the input contained that was + /// not expected. + /// + /// The message should be a noun or noun phrase, not capitalized and without + /// a period. An example message is "unoriginal superhero". + Other(&'a str), +} + +impl<'a> fmt::Display for Unexpected<'a> { + fn fmt(&self, formatter: &mut fmt::Formatter) -> fmt::Result { + use self::Unexpected::*; + match *self { + Bool(b) => write!(formatter, "boolean `{}`", b), + Unsigned(i) => write!(formatter, "integer `{}`", i), + Signed(i) => write!(formatter, "integer `{}`", i), + Float(f) => write!(formatter, "floating point `{}`", f), + Char(c) => write!(formatter, "character `{}`", c), + Str(s) => write!(formatter, "string {:?}", s), + Bytes(_) => write!(formatter, "byte array"), + Unit => write!(formatter, "unit value"), + Option => write!(formatter, "Option value"), + NewtypeStruct => write!(formatter, "newtype struct"), + Seq => write!(formatter, "sequence"), + Map => write!(formatter, "map"), + Enum => write!(formatter, "enum"), + UnitVariant => write!(formatter, "unit variant"), + NewtypeVariant => write!(formatter, "newtype variant"), + TupleVariant => write!(formatter, "tuple variant"), + StructVariant => write!(formatter, "struct variant"), + Other(other) => formatter.write_str(other), + } + } +} + +/// `Expected` represents an explanation of what data a `Visitor` was expecting +/// to receive. +/// +/// This is used as an argument to the `invalid_type`, `invalid_value`, and +/// `invalid_length` methods of the `Error` trait to build error messages. The +/// message should be a noun or noun phrase that completes the sentence "This +/// Visitor expects to receive ...", for example the message could be "an +/// integer between 0 and 64". The message should not be capitalized and should +/// not end with a period. +/// +/// Within the context of a `Visitor` implementation, the `Visitor` itself +/// (`&self`) is an implementation of this trait. +/// +/// ```edition2018 +/// # use std::fmt; +/// # +/// # use serde::de::{self, Unexpected, Visitor}; +/// # +/// # struct Example; +/// # +/// # impl<'de> Visitor<'de> for Example { +/// # type Value = (); +/// # +/// # fn expecting(&self, formatter: &mut fmt::Formatter) -> fmt::Result { +/// # write!(formatter, "definitely not a boolean") +/// # } +/// # +/// fn visit_bool<E>(self, v: bool) -> Result<Self::Value, E> +/// where +/// E: de::Error, +/// { +/// Err(de::Error::invalid_type(Unexpected::Bool(v), &self)) +/// } +/// # } +/// ``` +/// +/// Outside of a `Visitor`, `&"..."` can be used. +/// +/// ```edition2018 +/// # use serde::de::{self, Unexpected}; +/// # +/// # fn example<E>() -> Result<(), E> +/// # where +/// # E: de::Error, +/// # { +/// # let v = true; +/// return Err(de::Error::invalid_type(Unexpected::Bool(v), &"a negative integer")); +/// # } +/// ``` +pub trait Expected { + /// Format an explanation of what data was being expected. Same signature as + /// the `Display` and `Debug` traits. + fn fmt(&self, formatter: &mut fmt::Formatter) -> fmt::Result; +} + +impl<'de, T> Expected for T +where + T: Visitor<'de>, +{ + fn fmt(&self, formatter: &mut fmt::Formatter) -> fmt::Result { + self.expecting(formatter) + } +} + +impl<'a> Expected for &'a str { + fn fmt(&self, formatter: &mut fmt::Formatter) -> fmt::Result { + formatter.write_str(self) + } +} + +impl<'a> Display for Expected + 'a { + fn fmt(&self, formatter: &mut fmt::Formatter) -> fmt::Result { + Expected::fmt(self, formatter) + } +} + +//////////////////////////////////////////////////////////////////////////////// + +/// A **data structure** that can be deserialized from any data format supported +/// by Serde. +/// +/// Serde provides `Deserialize` implementations for many Rust primitive and +/// standard library types. The complete list is [here][crate::de]. All of these +/// can be deserialized using Serde out of the box. +/// +/// Additionally, Serde provides a procedural macro called `serde_derive` to +/// automatically generate `Deserialize` implementations for structs and enums +/// in your program. See the [derive section of the manual][derive] for how to +/// use this. +/// +/// In rare cases it may be necessary to implement `Deserialize` manually for +/// some type in your program. See the [Implementing +/// `Deserialize`][impl-deserialize] section of the manual for more about this. +/// +/// Third-party crates may provide `Deserialize` implementations for types that +/// they expose. For example the `linked-hash-map` crate provides a +/// `LinkedHashMap<K, V>` type that is deserializable by Serde because the crate +/// provides an implementation of `Deserialize` for it. +/// +/// [derive]: https://serde.rs/derive.html +/// [impl-deserialize]: https://serde.rs/impl-deserialize.html +/// +/// # Lifetime +/// +/// The `'de` lifetime of this trait is the lifetime of data that may be +/// borrowed by `Self` when deserialized. See the page [Understanding +/// deserializer lifetimes] for a more detailed explanation of these lifetimes. +/// +/// [Understanding deserializer lifetimes]: https://serde.rs/lifetimes.html +pub trait Deserialize<'de>: Sized { + /// Deserialize this value from the given Serde deserializer. + /// + /// See the [Implementing `Deserialize`][impl-deserialize] section of the + /// manual for more information about how to implement this method. + /// + /// [impl-deserialize]: https://serde.rs/impl-deserialize.html + fn deserialize<D>(deserializer: D) -> Result<Self, D::Error> + where + D: Deserializer<'de>; + + /// Deserializes a value into `self` from the given Deserializer. + /// + /// The purpose of this method is to allow the deserializer to reuse + /// resources and avoid copies. As such, if this method returns an error, + /// `self` will be in an indeterminate state where some parts of the struct + /// have been overwritten. Although whatever state that is will be + /// memory-safe. + /// + /// This is generally useful when repeatedly deserializing values that + /// are processed one at a time, where the value of `self` doesn't matter + /// when the next deserialization occurs. + /// + /// If you manually implement this, your recursive deserializations should + /// use `deserialize_in_place`. + /// + /// This method is stable and an official public API, but hidden from the + /// documentation because it is almost never what newbies are looking for. + /// Showing it in rustdoc would cause it to be featured more prominently + /// than it deserves. + #[doc(hidden)] + fn deserialize_in_place<D>(deserializer: D, place: &mut Self) -> Result<(), D::Error> + where + D: Deserializer<'de>, + { + // Default implementation just delegates to `deserialize` impl. + *place = try!(Deserialize::deserialize(deserializer)); + Ok(()) + } +} + +/// A data structure that can be deserialized without borrowing any data from +/// the deserializer. +/// +/// This is primarily useful for trait bounds on functions. For example a +/// `from_str` function may be able to deserialize a data structure that borrows +/// from the input string, but a `from_reader` function may only deserialize +/// owned data. +/// +/// ```edition2018 +/// # use serde::de::{Deserialize, DeserializeOwned}; +/// # use std::io::{Read, Result}; +/// # +/// # trait Ignore { +/// fn from_str<'a, T>(s: &'a str) -> Result<T> +/// where +/// T: Deserialize<'a>; +/// +/// fn from_reader<R, T>(rdr: R) -> Result<T> +/// where +/// R: Read, +/// T: DeserializeOwned; +/// # } +/// ``` +/// +/// # Lifetime +/// +/// The relationship between `Deserialize` and `DeserializeOwned` in trait +/// bounds is explained in more detail on the page [Understanding deserializer +/// lifetimes]. +/// +/// [Understanding deserializer lifetimes]: https://serde.rs/lifetimes.html +pub trait DeserializeOwned: for<'de> Deserialize<'de> {} +impl<T> DeserializeOwned for T where T: for<'de> Deserialize<'de> {} + +/// `DeserializeSeed` is the stateful form of the `Deserialize` trait. If you +/// ever find yourself looking for a way to pass data into a `Deserialize` impl, +/// this trait is the way to do it. +/// +/// As one example of stateful deserialization consider deserializing a JSON +/// array into an existing buffer. Using the `Deserialize` trait we could +/// deserialize a JSON array into a `Vec<T>` but it would be a freshly allocated +/// `Vec<T>`; there is no way for `Deserialize` to reuse a previously allocated +/// buffer. Using `DeserializeSeed` instead makes this possible as in the +/// example code below. +/// +/// The canonical API for stateless deserialization looks like this: +/// +/// ```edition2018 +/// # use serde::Deserialize; +/// # +/// # enum Error {} +/// # +/// fn func<'de, T: Deserialize<'de>>() -> Result<T, Error> +/// # { +/// # unimplemented!() +/// # } +/// ``` +/// +/// Adjusting an API like this to support stateful deserialization is a matter +/// of accepting a seed as input: +/// +/// ```edition2018 +/// # use serde::de::DeserializeSeed; +/// # +/// # enum Error {} +/// # +/// fn func_seed<'de, T: DeserializeSeed<'de>>(seed: T) -> Result<T::Value, Error> +/// # { +/// # let _ = seed; +/// # unimplemented!() +/// # } +/// ``` +/// +/// In practice the majority of deserialization is stateless. An API expecting a +/// seed can be appeased by passing `std::marker::PhantomData` as a seed in the +/// case of stateless deserialization. +/// +/// # Lifetime +/// +/// The `'de` lifetime of this trait is the lifetime of data that may be +/// borrowed by `Self::Value` when deserialized. See the page [Understanding +/// deserializer lifetimes] for a more detailed explanation of these lifetimes. +/// +/// [Understanding deserializer lifetimes]: https://serde.rs/lifetimes.html +/// +/// # Example +/// +/// Suppose we have JSON that looks like `[[1, 2], [3, 4, 5], [6]]` and we need +/// to deserialize it into a flat representation like `vec![1, 2, 3, 4, 5, 6]`. +/// Allocating a brand new `Vec<T>` for each subarray would be slow. Instead we +/// would like to allocate a single `Vec<T>` and then deserialize each subarray +/// into it. This requires stateful deserialization using the `DeserializeSeed` +/// trait. +/// +/// ```edition2018 +/// use std::fmt; +/// use std::marker::PhantomData; +/// +/// use serde::de::{Deserialize, DeserializeSeed, Deserializer, SeqAccess, Visitor}; +/// +/// // A DeserializeSeed implementation that uses stateful deserialization to +/// // append array elements onto the end of an existing vector. The preexisting +/// // state ("seed") in this case is the Vec<T>. The `deserialize` method of +/// // `ExtendVec` will be traversing the inner arrays of the JSON input and +/// // appending each integer into the existing Vec. +/// struct ExtendVec<'a, T: 'a>(&'a mut Vec<T>); +/// +/// impl<'de, 'a, T> DeserializeSeed<'de> for ExtendVec<'a, T> +/// where +/// T: Deserialize<'de>, +/// { +/// // The return type of the `deserialize` method. This implementation +/// // appends onto an existing vector but does not create any new data +/// // structure, so the return type is (). +/// type Value = (); +/// +/// fn deserialize<D>(self, deserializer: D) -> Result<Self::Value, D::Error> +/// where +/// D: Deserializer<'de>, +/// { +/// // Visitor implementation that will walk an inner array of the JSON +/// // input. +/// struct ExtendVecVisitor<'a, T: 'a>(&'a mut Vec<T>); +/// +/// impl<'de, 'a, T> Visitor<'de> for ExtendVecVisitor<'a, T> +/// where +/// T: Deserialize<'de>, +/// { +/// type Value = (); +/// +/// fn expecting(&self, formatter: &mut fmt::Formatter) -> fmt::Result { +/// write!(formatter, "an array of integers") +/// } +/// +/// fn visit_seq<A>(self, mut seq: A) -> Result<(), A::Error> +/// where +/// A: SeqAccess<'de>, +/// { +/// // Decrease the number of reallocations if there are many elements +/// if let Some(size_hint) = seq.size_hint() { +/// self.0.reserve(size_hint); +/// } +/// +/// // Visit each element in the inner array and push it onto +/// // the existing vector. +/// while let Some(elem) = seq.next_element()? { +/// self.0.push(elem); +/// } +/// Ok(()) +/// } +/// } +/// +/// deserializer.deserialize_seq(ExtendVecVisitor(self.0)) +/// } +/// } +/// +/// // Visitor implementation that will walk the outer array of the JSON input. +/// struct FlattenedVecVisitor<T>(PhantomData<T>); +/// +/// impl<'de, T> Visitor<'de> for FlattenedVecVisitor<T> +/// where +/// T: Deserialize<'de>, +/// { +/// // This Visitor constructs a single Vec<T> to hold the flattened +/// // contents of the inner arrays. +/// type Value = Vec<T>; +/// +/// fn expecting(&self, formatter: &mut fmt::Formatter) -> fmt::Result { +/// write!(formatter, "an array of arrays") +/// } +/// +/// fn visit_seq<A>(self, mut seq: A) -> Result<Vec<T>, A::Error> +/// where +/// A: SeqAccess<'de>, +/// { +/// // Create a single Vec to hold the flattened contents. +/// let mut vec = Vec::new(); +/// +/// // Each iteration through this loop is one inner array. +/// while let Some(()) = seq.next_element_seed(ExtendVec(&mut vec))? { +/// // Nothing to do; inner array has been appended into `vec`. +/// } +/// +/// // Return the finished vec. +/// Ok(vec) +/// } +/// } +/// +/// # fn example<'de, D>(deserializer: D) -> Result<(), D::Error> +/// # where +/// # D: Deserializer<'de>, +/// # { +/// let visitor = FlattenedVecVisitor(PhantomData); +/// let flattened: Vec<u64> = deserializer.deserialize_seq(visitor)?; +/// # Ok(()) +/// # } +/// ``` +pub trait DeserializeSeed<'de>: Sized { + /// The type produced by using this seed. + type Value; + + /// Equivalent to the more common `Deserialize::deserialize` method, except + /// with some initial piece of data (the seed) passed in. + fn deserialize<D>(self, deserializer: D) -> Result<Self::Value, D::Error> + where + D: Deserializer<'de>; +} + +impl<'de, T> DeserializeSeed<'de> for PhantomData<T> +where + T: Deserialize<'de>, +{ + type Value = T; + + #[inline] + fn deserialize<D>(self, deserializer: D) -> Result<T, D::Error> + where + D: Deserializer<'de>, + { + T::deserialize(deserializer) + } +} + +//////////////////////////////////////////////////////////////////////////////// + +/// A **data format** that can deserialize any data structure supported by +/// Serde. +/// +/// The role of this trait is to define the deserialization half of the [Serde +/// data model], which is a way to categorize every Rust data type into one of +/// 29 possible types. Each method of the `Deserializer` trait corresponds to one +/// of the types of the data model. +/// +/// Implementations of `Deserialize` map themselves into this data model by +/// passing to the `Deserializer` a `Visitor` implementation that can receive +/// these various types. +/// +/// The types that make up the Serde data model are: +/// +/// - **14 primitive types** +/// - bool +/// - i8, i16, i32, i64, i128 +/// - u8, u16, u32, u64, u128 +/// - f32, f64 +/// - char +/// - **string** +/// - UTF-8 bytes with a length and no null terminator. +/// - When serializing, all strings are handled equally. When deserializing, +/// there are three flavors of strings: transient, owned, and borrowed. +/// - **byte array** - \[u8\] +/// - Similar to strings, during deserialization byte arrays can be +/// transient, owned, or borrowed. +/// - **option** +/// - Either none or some value. +/// - **unit** +/// - The type of `()` in Rust. It represents an anonymous value containing +/// no data. +/// - **unit_struct** +/// - For example `struct Unit` or `PhantomData<T>`. It represents a named +/// value containing no data. +/// - **unit_variant** +/// - For example the `E::A` and `E::B` in `enum E { A, B }`. +/// - **newtype_struct** +/// - For example `struct Millimeters(u8)`. +/// - **newtype_variant** +/// - For example the `E::N` in `enum E { N(u8) }`. +/// - **seq** +/// - A variably sized heterogeneous sequence of values, for example `Vec<T>` +/// or `HashSet<T>`. When serializing, the length may or may not be known +/// before iterating through all the data. When deserializing, the length +/// is determined by looking at the serialized data. +/// - **tuple** +/// - A statically sized heterogeneous sequence of values for which the +/// length will be known at deserialization time without looking at the +/// serialized data, for example `(u8,)` or `(String, u64, Vec<T>)` or +/// `[u64; 10]`. +/// - **tuple_struct** +/// - A named tuple, for example `struct Rgb(u8, u8, u8)`. +/// - **tuple_variant** +/// - For example the `E::T` in `enum E { T(u8, u8) }`. +/// - **map** +/// - A heterogeneous key-value pairing, for example `BTreeMap<K, V>`. +/// - **struct** +/// - A heterogeneous key-value pairing in which the keys are strings and +/// will be known at deserialization time without looking at the serialized +/// data, for example `struct S { r: u8, g: u8, b: u8 }`. +/// - **struct_variant** +/// - For example the `E::S` in `enum E { S { r: u8, g: u8, b: u8 } }`. +/// +/// The `Deserializer` trait supports two entry point styles which enables +/// different kinds of deserialization. +/// +/// 1. The `deserialize_any` method. Self-describing data formats like JSON are +/// able to look at the serialized data and tell what it represents. For +/// example the JSON deserializer may see an opening curly brace (`{`) and +/// know that it is seeing a map. If the data format supports +/// `Deserializer::deserialize_any`, it will drive the Visitor using whatever +/// type it sees in the input. JSON uses this approach when deserializing +/// `serde_json::Value` which is an enum that can represent any JSON +/// document. Without knowing what is in a JSON document, we can deserialize +/// it to `serde_json::Value` by going through +/// `Deserializer::deserialize_any`. +/// +/// 2. The various `deserialize_*` methods. Non-self-describing formats like +/// Postcard need to be told what is in the input in order to deserialize it. +/// The `deserialize_*` methods are hints to the deserializer for how to +/// interpret the next piece of input. Non-self-describing formats are not +/// able to deserialize something like `serde_json::Value` which relies on +/// `Deserializer::deserialize_any`. +/// +/// When implementing `Deserialize`, you should avoid relying on +/// `Deserializer::deserialize_any` unless you need to be told by the +/// Deserializer what type is in the input. Know that relying on +/// `Deserializer::deserialize_any` means your data type will be able to +/// deserialize from self-describing formats only, ruling out Postcard and many +/// others. +/// +/// [Serde data model]: https://serde.rs/data-model.html +/// +/// # Lifetime +/// +/// The `'de` lifetime of this trait is the lifetime of data that may be +/// borrowed from the input when deserializing. See the page [Understanding +/// deserializer lifetimes] for a more detailed explanation of these lifetimes. +/// +/// [Understanding deserializer lifetimes]: https://serde.rs/lifetimes.html +/// +/// # Example implementation +/// +/// The [example data format] presented on the website contains example code for +/// a basic JSON `Deserializer`. +/// +/// [example data format]: https://serde.rs/data-format.html +pub trait Deserializer<'de>: Sized { + /// The error type that can be returned if some error occurs during + /// deserialization. + type Error: Error; + + /// Require the `Deserializer` to figure out how to drive the visitor based + /// on what data type is in the input. + /// + /// When implementing `Deserialize`, you should avoid relying on + /// `Deserializer::deserialize_any` unless you need to be told by the + /// Deserializer what type is in the input. Know that relying on + /// `Deserializer::deserialize_any` means your data type will be able to + /// deserialize from self-describing formats only, ruling out Postcard and + /// many others. + fn deserialize_any<V>(self, visitor: V) -> Result<V::Value, Self::Error> + where + V: Visitor<'de>; + + /// Hint that the `Deserialize` type is expecting a `bool` value. + fn deserialize_bool<V>(self, visitor: V) -> Result<V::Value, Self::Error> + where + V: Visitor<'de>; + + /// Hint that the `Deserialize` type is expecting an `i8` value. + fn deserialize_i8<V>(self, visitor: V) -> Result<V::Value, Self::Error> + where + V: Visitor<'de>; + + /// Hint that the `Deserialize` type is expecting an `i16` value. + fn deserialize_i16<V>(self, visitor: V) -> Result<V::Value, Self::Error> + where + V: Visitor<'de>; + + /// Hint that the `Deserialize` type is expecting an `i32` value. + fn deserialize_i32<V>(self, visitor: V) -> Result<V::Value, Self::Error> + where + V: Visitor<'de>; + + /// Hint that the `Deserialize` type is expecting an `i64` value. + fn deserialize_i64<V>(self, visitor: V) -> Result<V::Value, Self::Error> + where + V: Visitor<'de>; + + serde_if_integer128! { + /// Hint that the `Deserialize` type is expecting an `i128` value. + /// + /// This method is available only on Rust compiler versions >=1.26. The + /// default behavior unconditionally returns an error. + fn deserialize_i128<V>(self, visitor: V) -> Result<V::Value, Self::Error> + where + V: Visitor<'de> + { + let _ = visitor; + Err(Error::custom("i128 is not supported")) + } + } + + /// Hint that the `Deserialize` type is expecting a `u8` value. + fn deserialize_u8<V>(self, visitor: V) -> Result<V::Value, Self::Error> + where + V: Visitor<'de>; + + /// Hint that the `Deserialize` type is expecting a `u16` value. + fn deserialize_u16<V>(self, visitor: V) -> Result<V::Value, Self::Error> + where + V: Visitor<'de>; + + /// Hint that the `Deserialize` type is expecting a `u32` value. + fn deserialize_u32<V>(self, visitor: V) -> Result<V::Value, Self::Error> + where + V: Visitor<'de>; + + /// Hint that the `Deserialize` type is expecting a `u64` value. + fn deserialize_u64<V>(self, visitor: V) -> Result<V::Value, Self::Error> + where + V: Visitor<'de>; + + serde_if_integer128! { + /// Hint that the `Deserialize` type is expecting an `u128` value. + /// + /// This method is available only on Rust compiler versions >=1.26. The + /// default behavior unconditionally returns an error. + fn deserialize_u128<V>(self, visitor: V) -> Result<V::Value, Self::Error> + where + V: Visitor<'de> + { + let _ = visitor; + Err(Error::custom("u128 is not supported")) + } + } + + /// Hint that the `Deserialize` type is expecting a `f32` value. + fn deserialize_f32<V>(self, visitor: V) -> Result<V::Value, Self::Error> + where + V: Visitor<'de>; + + /// Hint that the `Deserialize` type is expecting a `f64` value. + fn deserialize_f64<V>(self, visitor: V) -> Result<V::Value, Self::Error> + where + V: Visitor<'de>; + + /// Hint that the `Deserialize` type is expecting a `char` value. + fn deserialize_char<V>(self, visitor: V) -> Result<V::Value, Self::Error> + where + V: Visitor<'de>; + + /// Hint that the `Deserialize` type is expecting a string value and does + /// not benefit from taking ownership of buffered data owned by the + /// `Deserializer`. + /// + /// If the `Visitor` would benefit from taking ownership of `String` data, + /// indicate this to the `Deserializer` by using `deserialize_string` + /// instead. + fn deserialize_str<V>(self, visitor: V) -> Result<V::Value, Self::Error> + where + V: Visitor<'de>; + + /// Hint that the `Deserialize` type is expecting a string value and would + /// benefit from taking ownership of buffered data owned by the + /// `Deserializer`. + /// + /// If the `Visitor` would not benefit from taking ownership of `String` + /// data, indicate that to the `Deserializer` by using `deserialize_str` + /// instead. + fn deserialize_string<V>(self, visitor: V) -> Result<V::Value, Self::Error> + where + V: Visitor<'de>; + + /// Hint that the `Deserialize` type is expecting a byte array and does not + /// benefit from taking ownership of buffered data owned by the + /// `Deserializer`. + /// + /// If the `Visitor` would benefit from taking ownership of `Vec<u8>` data, + /// indicate this to the `Deserializer` by using `deserialize_byte_buf` + /// instead. + fn deserialize_bytes<V>(self, visitor: V) -> Result<V::Value, Self::Error> + where + V: Visitor<'de>; + + /// Hint that the `Deserialize` type is expecting a byte array and would + /// benefit from taking ownership of buffered data owned by the + /// `Deserializer`. + /// + /// If the `Visitor` would not benefit from taking ownership of `Vec<u8>` + /// data, indicate that to the `Deserializer` by using `deserialize_bytes` + /// instead. + fn deserialize_byte_buf<V>(self, visitor: V) -> Result<V::Value, Self::Error> + where + V: Visitor<'de>; + + /// Hint that the `Deserialize` type is expecting an optional value. + /// + /// This allows deserializers that encode an optional value as a nullable + /// value to convert the null value into `None` and a regular value into + /// `Some(value)`. + fn deserialize_option<V>(self, visitor: V) -> Result<V::Value, Self::Error> + where + V: Visitor<'de>; + + /// Hint that the `Deserialize` type is expecting a unit value. + fn deserialize_unit<V>(self, visitor: V) -> Result<V::Value, Self::Error> + where + V: Visitor<'de>; + + /// Hint that the `Deserialize` type is expecting a unit struct with a + /// particular name. + fn deserialize_unit_struct<V>( + self, + name: &'static str, + visitor: V, + ) -> Result<V::Value, Self::Error> + where + V: Visitor<'de>; + + /// Hint that the `Deserialize` type is expecting a newtype struct with a + /// particular name. + fn deserialize_newtype_struct<V>( + self, + name: &'static str, + visitor: V, + ) -> Result<V::Value, Self::Error> + where + V: Visitor<'de>; + + /// Hint that the `Deserialize` type is expecting a sequence of values. + fn deserialize_seq<V>(self, visitor: V) -> Result<V::Value, Self::Error> + where + V: Visitor<'de>; + + /// Hint that the `Deserialize` type is expecting a sequence of values and + /// knows how many values there are without looking at the serialized data. + fn deserialize_tuple<V>(self, len: usize, visitor: V) -> Result<V::Value, Self::Error> + where + V: Visitor<'de>; + + /// Hint that the `Deserialize` type is expecting a tuple struct with a + /// particular name and number of fields. + fn deserialize_tuple_struct<V>( + self, + name: &'static str, + len: usize, + visitor: V, + ) -> Result<V::Value, Self::Error> + where + V: Visitor<'de>; + + /// Hint that the `Deserialize` type is expecting a map of key-value pairs. + fn deserialize_map<V>(self, visitor: V) -> Result<V::Value, Self::Error> + where + V: Visitor<'de>; + + /// Hint that the `Deserialize` type is expecting a struct with a particular + /// name and fields. + fn deserialize_struct<V>( + self, + name: &'static str, + fields: &'static [&'static str], + visitor: V, + ) -> Result<V::Value, Self::Error> + where + V: Visitor<'de>; + + /// Hint that the `Deserialize` type is expecting an enum value with a + /// particular name and possible variants. + fn deserialize_enum<V>( + self, + name: &'static str, + variants: &'static [&'static str], + visitor: V, + ) -> Result<V::Value, Self::Error> + where + V: Visitor<'de>; + + /// Hint that the `Deserialize` type is expecting the name of a struct + /// field or the discriminant of an enum variant. + fn deserialize_identifier<V>(self, visitor: V) -> Result<V::Value, Self::Error> + where + V: Visitor<'de>; + + /// Hint that the `Deserialize` type needs to deserialize a value whose type + /// doesn't matter because it is ignored. + /// + /// Deserializers for non-self-describing formats may not support this mode. + fn deserialize_ignored_any<V>(self, visitor: V) -> Result<V::Value, Self::Error> + where + V: Visitor<'de>; + + /// Determine whether `Deserialize` implementations should expect to + /// deserialize their human-readable form. + /// + /// Some types have a human-readable form that may be somewhat expensive to + /// construct, as well as a binary form that is compact and efficient. + /// Generally text-based formats like JSON and YAML will prefer to use the + /// human-readable one and binary formats like Postcard will prefer the + /// compact one. + /// + /// ```edition2018 + /// # use std::ops::Add; + /// # use std::str::FromStr; + /// # + /// # struct Timestamp; + /// # + /// # impl Timestamp { + /// # const EPOCH: Timestamp = Timestamp; + /// # } + /// # + /// # impl FromStr for Timestamp { + /// # type Err = String; + /// # fn from_str(_: &str) -> Result<Self, Self::Err> { + /// # unimplemented!() + /// # } + /// # } + /// # + /// # struct Duration; + /// # + /// # impl Duration { + /// # fn seconds(_: u64) -> Self { unimplemented!() } + /// # } + /// # + /// # impl Add<Duration> for Timestamp { + /// # type Output = Timestamp; + /// # fn add(self, _: Duration) -> Self::Output { + /// # unimplemented!() + /// # } + /// # } + /// # + /// use serde::de::{self, Deserialize, Deserializer}; + /// + /// impl<'de> Deserialize<'de> for Timestamp { + /// fn deserialize<D>(deserializer: D) -> Result<Self, D::Error> + /// where + /// D: Deserializer<'de>, + /// { + /// if deserializer.is_human_readable() { + /// // Deserialize from a human-readable string like "2015-05-15T17:01:00Z". + /// let s = String::deserialize(deserializer)?; + /// Timestamp::from_str(&s).map_err(de::Error::custom) + /// } else { + /// // Deserialize from a compact binary representation, seconds since + /// // the Unix epoch. + /// let n = u64::deserialize(deserializer)?; + /// Ok(Timestamp::EPOCH + Duration::seconds(n)) + /// } + /// } + /// } + /// ``` + /// + /// The default implementation of this method returns `true`. Data formats + /// may override this to `false` to request a compact form for types that + /// support one. Note that modifying this method to change a format from + /// human-readable to compact or vice versa should be regarded as a breaking + /// change, as a value serialized in human-readable mode is not required to + /// deserialize from the same data in compact mode. + #[inline] + fn is_human_readable(&self) -> bool { + true + } + + // Not public API. + #[cfg(all(not(no_serde_derive), any(feature = "std", feature = "alloc")))] + #[doc(hidden)] + fn __deserialize_content<V>( + self, + _: ::actually_private::T, + visitor: V, + ) -> Result<::private::de::Content<'de>, Self::Error> + where + V: Visitor<'de, Value = ::private::de::Content<'de>>, + { + self.deserialize_any(visitor) + } +} + +//////////////////////////////////////////////////////////////////////////////// + +/// This trait represents a visitor that walks through a deserializer. +/// +/// # Lifetime +/// +/// The `'de` lifetime of this trait is the requirement for lifetime of data +/// that may be borrowed by `Self::Value`. See the page [Understanding +/// deserializer lifetimes] for a more detailed explanation of these lifetimes. +/// +/// [Understanding deserializer lifetimes]: https://serde.rs/lifetimes.html +/// +/// # Example +/// +/// ```edition2018 +/// # use std::fmt; +/// # +/// # use serde::de::{self, Unexpected, Visitor}; +/// # +/// /// A visitor that deserializes a long string - a string containing at least +/// /// some minimum number of bytes. +/// struct LongString { +/// min: usize, +/// } +/// +/// impl<'de> Visitor<'de> for LongString { +/// type Value = String; +/// +/// fn expecting(&self, formatter: &mut fmt::Formatter) -> fmt::Result { +/// write!(formatter, "a string containing at least {} bytes", self.min) +/// } +/// +/// fn visit_str<E>(self, s: &str) -> Result<Self::Value, E> +/// where +/// E: de::Error, +/// { +/// if s.len() >= self.min { +/// Ok(s.to_owned()) +/// } else { +/// Err(de::Error::invalid_value(Unexpected::Str(s), &self)) +/// } +/// } +/// } +/// ``` +pub trait Visitor<'de>: Sized { + /// The value produced by this visitor. + type Value; + + /// Format a message stating what data this Visitor expects to receive. + /// + /// This is used in error messages. The message should complete the sentence + /// "This Visitor expects to receive ...", for example the message could be + /// "an integer between 0 and 64". The message should not be capitalized and + /// should not end with a period. + /// + /// ```edition2018 + /// # use std::fmt; + /// # + /// # struct S { + /// # max: usize, + /// # } + /// # + /// # impl<'de> serde::de::Visitor<'de> for S { + /// # type Value = (); + /// # + /// fn expecting(&self, formatter: &mut fmt::Formatter) -> fmt::Result { + /// write!(formatter, "an integer between 0 and {}", self.max) + /// } + /// # } + /// ``` + fn expecting(&self, formatter: &mut fmt::Formatter) -> fmt::Result; + + /// The input contains a boolean. + /// + /// The default implementation fails with a type error. + fn visit_bool<E>(self, v: bool) -> Result<Self::Value, E> + where + E: Error, + { + Err(Error::invalid_type(Unexpected::Bool(v), &self)) + } + + /// The input contains an `i8`. + /// + /// The default implementation forwards to [`visit_i64`]. + /// + /// [`visit_i64`]: #method.visit_i64 + fn visit_i8<E>(self, v: i8) -> Result<Self::Value, E> + where + E: Error, + { + self.visit_i64(v as i64) + } + + /// The input contains an `i16`. + /// + /// The default implementation forwards to [`visit_i64`]. + /// + /// [`visit_i64`]: #method.visit_i64 + fn visit_i16<E>(self, v: i16) -> Result<Self::Value, E> + where + E: Error, + { + self.visit_i64(v as i64) + } + + /// The input contains an `i32`. + /// + /// The default implementation forwards to [`visit_i64`]. + /// + /// [`visit_i64`]: #method.visit_i64 + fn visit_i32<E>(self, v: i32) -> Result<Self::Value, E> + where + E: Error, + { + self.visit_i64(v as i64) + } + + /// The input contains an `i64`. + /// + /// The default implementation fails with a type error. + fn visit_i64<E>(self, v: i64) -> Result<Self::Value, E> + where + E: Error, + { + Err(Error::invalid_type(Unexpected::Signed(v), &self)) + } + + serde_if_integer128! { + /// The input contains a `i128`. + /// + /// This method is available only on Rust compiler versions >=1.26. The + /// default implementation fails with a type error. + fn visit_i128<E>(self, v: i128) -> Result<Self::Value, E> + where + E: Error, + { + let mut buf = [0u8; 58]; + let mut writer = format::Buf::new(&mut buf); + fmt::Write::write_fmt(&mut writer, format_args!("integer `{}` as i128", v)).unwrap(); + Err(Error::invalid_type(Unexpected::Other(writer.as_str()), &self)) + } + } + + /// The input contains a `u8`. + /// + /// The default implementation forwards to [`visit_u64`]. + /// + /// [`visit_u64`]: #method.visit_u64 + fn visit_u8<E>(self, v: u8) -> Result<Self::Value, E> + where + E: Error, + { + self.visit_u64(v as u64) + } + + /// The input contains a `u16`. + /// + /// The default implementation forwards to [`visit_u64`]. + /// + /// [`visit_u64`]: #method.visit_u64 + fn visit_u16<E>(self, v: u16) -> Result<Self::Value, E> + where + E: Error, + { + self.visit_u64(v as u64) + } + + /// The input contains a `u32`. + /// + /// The default implementation forwards to [`visit_u64`]. + /// + /// [`visit_u64`]: #method.visit_u64 + fn visit_u32<E>(self, v: u32) -> Result<Self::Value, E> + where + E: Error, + { + self.visit_u64(v as u64) + } + + /// The input contains a `u64`. + /// + /// The default implementation fails with a type error. + fn visit_u64<E>(self, v: u64) -> Result<Self::Value, E> + where + E: Error, + { + Err(Error::invalid_type(Unexpected::Unsigned(v), &self)) + } + + serde_if_integer128! { + /// The input contains a `u128`. + /// + /// This method is available only on Rust compiler versions >=1.26. The + /// default implementation fails with a type error. + fn visit_u128<E>(self, v: u128) -> Result<Self::Value, E> + where + E: Error, + { + let mut buf = [0u8; 57]; + let mut writer = format::Buf::new(&mut buf); + fmt::Write::write_fmt(&mut writer, format_args!("integer `{}` as u128", v)).unwrap(); + Err(Error::invalid_type(Unexpected::Other(writer.as_str()), &self)) + } + } + + /// The input contains an `f32`. + /// + /// The default implementation forwards to [`visit_f64`]. + /// + /// [`visit_f64`]: #method.visit_f64 + fn visit_f32<E>(self, v: f32) -> Result<Self::Value, E> + where + E: Error, + { + self.visit_f64(v as f64) + } + + /// The input contains an `f64`. + /// + /// The default implementation fails with a type error. + fn visit_f64<E>(self, v: f64) -> Result<Self::Value, E> + where + E: Error, + { + Err(Error::invalid_type(Unexpected::Float(v), &self)) + } + + /// The input contains a `char`. + /// + /// The default implementation forwards to [`visit_str`] as a one-character + /// string. + /// + /// [`visit_str`]: #method.visit_str + #[inline] + fn visit_char<E>(self, v: char) -> Result<Self::Value, E> + where + E: Error, + { + self.visit_str(utf8::encode(v).as_str()) + } + + /// The input contains a string. The lifetime of the string is ephemeral and + /// it may be destroyed after this method returns. + /// + /// This method allows the `Deserializer` to avoid a copy by retaining + /// ownership of any buffered data. `Deserialize` implementations that do + /// not benefit from taking ownership of `String` data should indicate that + /// to the deserializer by using `Deserializer::deserialize_str` rather than + /// `Deserializer::deserialize_string`. + /// + /// It is never correct to implement `visit_string` without implementing + /// `visit_str`. Implement neither, both, or just `visit_str`. + fn visit_str<E>(self, v: &str) -> Result<Self::Value, E> + where + E: Error, + { + Err(Error::invalid_type(Unexpected::Str(v), &self)) + } + + /// The input contains a string that lives at least as long as the + /// `Deserializer`. + /// + /// This enables zero-copy deserialization of strings in some formats. For + /// example JSON input containing the JSON string `"borrowed"` can be + /// deserialized with zero copying into a `&'a str` as long as the input + /// data outlives `'a`. + /// + /// The default implementation forwards to `visit_str`. + #[inline] + fn visit_borrowed_str<E>(self, v: &'de str) -> Result<Self::Value, E> + where + E: Error, + { + self.visit_str(v) + } + + /// The input contains a string and ownership of the string is being given + /// to the `Visitor`. + /// + /// This method allows the `Visitor` to avoid a copy by taking ownership of + /// a string created by the `Deserializer`. `Deserialize` implementations + /// that benefit from taking ownership of `String` data should indicate that + /// to the deserializer by using `Deserializer::deserialize_string` rather + /// than `Deserializer::deserialize_str`, although not every deserializer + /// will honor such a request. + /// + /// It is never correct to implement `visit_string` without implementing + /// `visit_str`. Implement neither, both, or just `visit_str`. + /// + /// The default implementation forwards to `visit_str` and then drops the + /// `String`. + #[inline] + #[cfg(any(feature = "std", feature = "alloc"))] + fn visit_string<E>(self, v: String) -> Result<Self::Value, E> + where + E: Error, + { + self.visit_str(&v) + } + + /// The input contains a byte array. The lifetime of the byte array is + /// ephemeral and it may be destroyed after this method returns. + /// + /// This method allows the `Deserializer` to avoid a copy by retaining + /// ownership of any buffered data. `Deserialize` implementations that do + /// not benefit from taking ownership of `Vec<u8>` data should indicate that + /// to the deserializer by using `Deserializer::deserialize_bytes` rather + /// than `Deserializer::deserialize_byte_buf`. + /// + /// It is never correct to implement `visit_byte_buf` without implementing + /// `visit_bytes`. Implement neither, both, or just `visit_bytes`. + fn visit_bytes<E>(self, v: &[u8]) -> Result<Self::Value, E> + where + E: Error, + { + let _ = v; + Err(Error::invalid_type(Unexpected::Bytes(v), &self)) + } + + /// The input contains a byte array that lives at least as long as the + /// `Deserializer`. + /// + /// This enables zero-copy deserialization of bytes in some formats. For + /// example Postcard data containing bytes can be deserialized with zero + /// copying into a `&'a [u8]` as long as the input data outlives `'a`. + /// + /// The default implementation forwards to `visit_bytes`. + #[inline] + fn visit_borrowed_bytes<E>(self, v: &'de [u8]) -> Result<Self::Value, E> + where + E: Error, + { + self.visit_bytes(v) + } + + /// The input contains a byte array and ownership of the byte array is being + /// given to the `Visitor`. + /// + /// This method allows the `Visitor` to avoid a copy by taking ownership of + /// a byte buffer created by the `Deserializer`. `Deserialize` + /// implementations that benefit from taking ownership of `Vec<u8>` data + /// should indicate that to the deserializer by using + /// `Deserializer::deserialize_byte_buf` rather than + /// `Deserializer::deserialize_bytes`, although not every deserializer will + /// honor such a request. + /// + /// It is never correct to implement `visit_byte_buf` without implementing + /// `visit_bytes`. Implement neither, both, or just `visit_bytes`. + /// + /// The default implementation forwards to `visit_bytes` and then drops the + /// `Vec<u8>`. + #[cfg(any(feature = "std", feature = "alloc"))] + fn visit_byte_buf<E>(self, v: Vec<u8>) -> Result<Self::Value, E> + where + E: Error, + { + self.visit_bytes(&v) + } + + /// The input contains an optional that is absent. + /// + /// The default implementation fails with a type error. + fn visit_none<E>(self) -> Result<Self::Value, E> + where + E: Error, + { + Err(Error::invalid_type(Unexpected::Option, &self)) + } + + /// The input contains an optional that is present. + /// + /// The default implementation fails with a type error. + fn visit_some<D>(self, deserializer: D) -> Result<Self::Value, D::Error> + where + D: Deserializer<'de>, + { + let _ = deserializer; + Err(Error::invalid_type(Unexpected::Option, &self)) + } + + /// The input contains a unit `()`. + /// + /// The default implementation fails with a type error. + fn visit_unit<E>(self) -> Result<Self::Value, E> + where + E: Error, + { + Err(Error::invalid_type(Unexpected::Unit, &self)) + } + + /// The input contains a newtype struct. + /// + /// The content of the newtype struct may be read from the given + /// `Deserializer`. + /// + /// The default implementation fails with a type error. + fn visit_newtype_struct<D>(self, deserializer: D) -> Result<Self::Value, D::Error> + where + D: Deserializer<'de>, + { + let _ = deserializer; + Err(Error::invalid_type(Unexpected::NewtypeStruct, &self)) + } + + /// The input contains a sequence of elements. + /// + /// The default implementation fails with a type error. + fn visit_seq<A>(self, seq: A) -> Result<Self::Value, A::Error> + where + A: SeqAccess<'de>, + { + let _ = seq; + Err(Error::invalid_type(Unexpected::Seq, &self)) + } + + /// The input contains a key-value map. + /// + /// The default implementation fails with a type error. + fn visit_map<A>(self, map: A) -> Result<Self::Value, A::Error> + where + A: MapAccess<'de>, + { + let _ = map; + Err(Error::invalid_type(Unexpected::Map, &self)) + } + + /// The input contains an enum. + /// + /// The default implementation fails with a type error. + fn visit_enum<A>(self, data: A) -> Result<Self::Value, A::Error> + where + A: EnumAccess<'de>, + { + let _ = data; + Err(Error::invalid_type(Unexpected::Enum, &self)) + } + + // Used when deserializing a flattened Option field. Not public API. + #[doc(hidden)] + fn __private_visit_untagged_option<D>(self, _: D) -> Result<Self::Value, ()> + where + D: Deserializer<'de>, + { + Err(()) + } +} + +//////////////////////////////////////////////////////////////////////////////// + +/// Provides a `Visitor` access to each element of a sequence in the input. +/// +/// This is a trait that a `Deserializer` passes to a `Visitor` implementation, +/// which deserializes each item in a sequence. +/// +/// # Lifetime +/// +/// The `'de` lifetime of this trait is the lifetime of data that may be +/// borrowed by deserialized sequence elements. See the page [Understanding +/// deserializer lifetimes] for a more detailed explanation of these lifetimes. +/// +/// [Understanding deserializer lifetimes]: https://serde.rs/lifetimes.html +/// +/// # Example implementation +/// +/// The [example data format] presented on the website demonstrates an +/// implementation of `SeqAccess` for a basic JSON data format. +/// +/// [example data format]: https://serde.rs/data-format.html +pub trait SeqAccess<'de> { + /// The error type that can be returned if some error occurs during + /// deserialization. + type Error: Error; + + /// This returns `Ok(Some(value))` for the next value in the sequence, or + /// `Ok(None)` if there are no more remaining items. + /// + /// `Deserialize` implementations should typically use + /// `SeqAccess::next_element` instead. + fn next_element_seed<T>(&mut self, seed: T) -> Result<Option<T::Value>, Self::Error> + where + T: DeserializeSeed<'de>; + + /// This returns `Ok(Some(value))` for the next value in the sequence, or + /// `Ok(None)` if there are no more remaining items. + /// + /// This method exists as a convenience for `Deserialize` implementations. + /// `SeqAccess` implementations should not override the default behavior. + #[inline] + fn next_element<T>(&mut self) -> Result<Option<T>, Self::Error> + where + T: Deserialize<'de>, + { + self.next_element_seed(PhantomData) + } + + /// Returns the number of elements remaining in the sequence, if known. + #[inline] + fn size_hint(&self) -> Option<usize> { + None + } +} + +impl<'de, 'a, A: ?Sized> SeqAccess<'de> for &'a mut A +where + A: SeqAccess<'de>, +{ + type Error = A::Error; + + #[inline] + fn next_element_seed<T>(&mut self, seed: T) -> Result<Option<T::Value>, Self::Error> + where + T: DeserializeSeed<'de>, + { + (**self).next_element_seed(seed) + } + + #[inline] + fn next_element<T>(&mut self) -> Result<Option<T>, Self::Error> + where + T: Deserialize<'de>, + { + (**self).next_element() + } + + #[inline] + fn size_hint(&self) -> Option<usize> { + (**self).size_hint() + } +} + +//////////////////////////////////////////////////////////////////////////////// + +/// Provides a `Visitor` access to each entry of a map in the input. +/// +/// This is a trait that a `Deserializer` passes to a `Visitor` implementation. +/// +/// # Lifetime +/// +/// The `'de` lifetime of this trait is the lifetime of data that may be +/// borrowed by deserialized map entries. See the page [Understanding +/// deserializer lifetimes] for a more detailed explanation of these lifetimes. +/// +/// [Understanding deserializer lifetimes]: https://serde.rs/lifetimes.html +/// +/// # Example implementation +/// +/// The [example data format] presented on the website demonstrates an +/// implementation of `MapAccess` for a basic JSON data format. +/// +/// [example data format]: https://serde.rs/data-format.html +pub trait MapAccess<'de> { + /// The error type that can be returned if some error occurs during + /// deserialization. + type Error: Error; + + /// This returns `Ok(Some(key))` for the next key in the map, or `Ok(None)` + /// if there are no more remaining entries. + /// + /// `Deserialize` implementations should typically use + /// `MapAccess::next_key` or `MapAccess::next_entry` instead. + fn next_key_seed<K>(&mut self, seed: K) -> Result<Option<K::Value>, Self::Error> + where + K: DeserializeSeed<'de>; + + /// This returns a `Ok(value)` for the next value in the map. + /// + /// `Deserialize` implementations should typically use + /// `MapAccess::next_value` instead. + /// + /// # Panics + /// + /// Calling `next_value_seed` before `next_key_seed` is incorrect and is + /// allowed to panic or return bogus results. + fn next_value_seed<V>(&mut self, seed: V) -> Result<V::Value, Self::Error> + where + V: DeserializeSeed<'de>; + + /// This returns `Ok(Some((key, value)))` for the next (key-value) pair in + /// the map, or `Ok(None)` if there are no more remaining items. + /// + /// `MapAccess` implementations should override the default behavior if a + /// more efficient implementation is possible. + /// + /// `Deserialize` implementations should typically use + /// `MapAccess::next_entry` instead. + #[inline] + fn next_entry_seed<K, V>( + &mut self, + kseed: K, + vseed: V, + ) -> Result<Option<(K::Value, V::Value)>, Self::Error> + where + K: DeserializeSeed<'de>, + V: DeserializeSeed<'de>, + { + match try!(self.next_key_seed(kseed)) { + Some(key) => { + let value = try!(self.next_value_seed(vseed)); + Ok(Some((key, value))) + } + None => Ok(None), + } + } + + /// This returns `Ok(Some(key))` for the next key in the map, or `Ok(None)` + /// if there are no more remaining entries. + /// + /// This method exists as a convenience for `Deserialize` implementations. + /// `MapAccess` implementations should not override the default behavior. + #[inline] + fn next_key<K>(&mut self) -> Result<Option<K>, Self::Error> + where + K: Deserialize<'de>, + { + self.next_key_seed(PhantomData) + } + + /// This returns a `Ok(value)` for the next value in the map. + /// + /// This method exists as a convenience for `Deserialize` implementations. + /// `MapAccess` implementations should not override the default behavior. + /// + /// # Panics + /// + /// Calling `next_value` before `next_key` is incorrect and is allowed to + /// panic or return bogus results. + #[inline] + fn next_value<V>(&mut self) -> Result<V, Self::Error> + where + V: Deserialize<'de>, + { + self.next_value_seed(PhantomData) + } + + /// This returns `Ok(Some((key, value)))` for the next (key-value) pair in + /// the map, or `Ok(None)` if there are no more remaining items. + /// + /// This method exists as a convenience for `Deserialize` implementations. + /// `MapAccess` implementations should not override the default behavior. + #[inline] + fn next_entry<K, V>(&mut self) -> Result<Option<(K, V)>, Self::Error> + where + K: Deserialize<'de>, + V: Deserialize<'de>, + { + self.next_entry_seed(PhantomData, PhantomData) + } + + /// Returns the number of entries remaining in the map, if known. + #[inline] + fn size_hint(&self) -> Option<usize> { + None + } +} + +impl<'de, 'a, A: ?Sized> MapAccess<'de> for &'a mut A +where + A: MapAccess<'de>, +{ + type Error = A::Error; + + #[inline] + fn next_key_seed<K>(&mut self, seed: K) -> Result<Option<K::Value>, Self::Error> + where + K: DeserializeSeed<'de>, + { + (**self).next_key_seed(seed) + } + + #[inline] + fn next_value_seed<V>(&mut self, seed: V) -> Result<V::Value, Self::Error> + where + V: DeserializeSeed<'de>, + { + (**self).next_value_seed(seed) + } + + #[inline] + fn next_entry_seed<K, V>( + &mut self, + kseed: K, + vseed: V, + ) -> Result<Option<(K::Value, V::Value)>, Self::Error> + where + K: DeserializeSeed<'de>, + V: DeserializeSeed<'de>, + { + (**self).next_entry_seed(kseed, vseed) + } + + #[inline] + fn next_entry<K, V>(&mut self) -> Result<Option<(K, V)>, Self::Error> + where + K: Deserialize<'de>, + V: Deserialize<'de>, + { + (**self).next_entry() + } + + #[inline] + fn next_key<K>(&mut self) -> Result<Option<K>, Self::Error> + where + K: Deserialize<'de>, + { + (**self).next_key() + } + + #[inline] + fn next_value<V>(&mut self) -> Result<V, Self::Error> + where + V: Deserialize<'de>, + { + (**self).next_value() + } + + #[inline] + fn size_hint(&self) -> Option<usize> { + (**self).size_hint() + } +} + +//////////////////////////////////////////////////////////////////////////////// + +/// Provides a `Visitor` access to the data of an enum in the input. +/// +/// `EnumAccess` is created by the `Deserializer` and passed to the +/// `Visitor` in order to identify which variant of an enum to deserialize. +/// +/// # Lifetime +/// +/// The `'de` lifetime of this trait is the lifetime of data that may be +/// borrowed by the deserialized enum variant. See the page [Understanding +/// deserializer lifetimes] for a more detailed explanation of these lifetimes. +/// +/// [Understanding deserializer lifetimes]: https://serde.rs/lifetimes.html +/// +/// # Example implementation +/// +/// The [example data format] presented on the website demonstrates an +/// implementation of `EnumAccess` for a basic JSON data format. +/// +/// [example data format]: https://serde.rs/data-format.html +pub trait EnumAccess<'de>: Sized { + /// The error type that can be returned if some error occurs during + /// deserialization. + type Error: Error; + /// The `Visitor` that will be used to deserialize the content of the enum + /// variant. + type Variant: VariantAccess<'de, Error = Self::Error>; + + /// `variant` is called to identify which variant to deserialize. + /// + /// `Deserialize` implementations should typically use `EnumAccess::variant` + /// instead. + fn variant_seed<V>(self, seed: V) -> Result<(V::Value, Self::Variant), Self::Error> + where + V: DeserializeSeed<'de>; + + /// `variant` is called to identify which variant to deserialize. + /// + /// This method exists as a convenience for `Deserialize` implementations. + /// `EnumAccess` implementations should not override the default behavior. + #[inline] + fn variant<V>(self) -> Result<(V, Self::Variant), Self::Error> + where + V: Deserialize<'de>, + { + self.variant_seed(PhantomData) + } +} + +/// `VariantAccess` is a visitor that is created by the `Deserializer` and +/// passed to the `Deserialize` to deserialize the content of a particular enum +/// variant. +/// +/// # Lifetime +/// +/// The `'de` lifetime of this trait is the lifetime of data that may be +/// borrowed by the deserialized enum variant. See the page [Understanding +/// deserializer lifetimes] for a more detailed explanation of these lifetimes. +/// +/// [Understanding deserializer lifetimes]: https://serde.rs/lifetimes.html +/// +/// # Example implementation +/// +/// The [example data format] presented on the website demonstrates an +/// implementation of `VariantAccess` for a basic JSON data format. +/// +/// [example data format]: https://serde.rs/data-format.html +pub trait VariantAccess<'de>: Sized { + /// The error type that can be returned if some error occurs during + /// deserialization. Must match the error type of our `EnumAccess`. + type Error: Error; + + /// Called when deserializing a variant with no values. + /// + /// If the data contains a different type of variant, the following + /// `invalid_type` error should be constructed: + /// + /// ```edition2018 + /// # use serde::de::{self, value, DeserializeSeed, Visitor, VariantAccess, Unexpected}; + /// # + /// # struct X; + /// # + /// # impl<'de> VariantAccess<'de> for X { + /// # type Error = value::Error; + /// # + /// fn unit_variant(self) -> Result<(), Self::Error> { + /// // What the data actually contained; suppose it is a tuple variant. + /// let unexp = Unexpected::TupleVariant; + /// Err(de::Error::invalid_type(unexp, &"unit variant")) + /// } + /// # + /// # fn newtype_variant_seed<T>(self, _: T) -> Result<T::Value, Self::Error> + /// # where + /// # T: DeserializeSeed<'de>, + /// # { unimplemented!() } + /// # + /// # fn tuple_variant<V>(self, _: usize, _: V) -> Result<V::Value, Self::Error> + /// # where + /// # V: Visitor<'de>, + /// # { unimplemented!() } + /// # + /// # fn struct_variant<V>(self, _: &[&str], _: V) -> Result<V::Value, Self::Error> + /// # where + /// # V: Visitor<'de>, + /// # { unimplemented!() } + /// # } + /// ``` + fn unit_variant(self) -> Result<(), Self::Error>; + + /// Called when deserializing a variant with a single value. + /// + /// `Deserialize` implementations should typically use + /// `VariantAccess::newtype_variant` instead. + /// + /// If the data contains a different type of variant, the following + /// `invalid_type` error should be constructed: + /// + /// ```edition2018 + /// # use serde::de::{self, value, DeserializeSeed, Visitor, VariantAccess, Unexpected}; + /// # + /// # struct X; + /// # + /// # impl<'de> VariantAccess<'de> for X { + /// # type Error = value::Error; + /// # + /// # fn unit_variant(self) -> Result<(), Self::Error> { + /// # unimplemented!() + /// # } + /// # + /// fn newtype_variant_seed<T>(self, _seed: T) -> Result<T::Value, Self::Error> + /// where + /// T: DeserializeSeed<'de>, + /// { + /// // What the data actually contained; suppose it is a unit variant. + /// let unexp = Unexpected::UnitVariant; + /// Err(de::Error::invalid_type(unexp, &"newtype variant")) + /// } + /// # + /// # fn tuple_variant<V>(self, _: usize, _: V) -> Result<V::Value, Self::Error> + /// # where + /// # V: Visitor<'de>, + /// # { unimplemented!() } + /// # + /// # fn struct_variant<V>(self, _: &[&str], _: V) -> Result<V::Value, Self::Error> + /// # where + /// # V: Visitor<'de>, + /// # { unimplemented!() } + /// # } + /// ``` + fn newtype_variant_seed<T>(self, seed: T) -> Result<T::Value, Self::Error> + where + T: DeserializeSeed<'de>; + + /// Called when deserializing a variant with a single value. + /// + /// This method exists as a convenience for `Deserialize` implementations. + /// `VariantAccess` implementations should not override the default + /// behavior. + #[inline] + fn newtype_variant<T>(self) -> Result<T, Self::Error> + where + T: Deserialize<'de>, + { + self.newtype_variant_seed(PhantomData) + } + + /// Called when deserializing a tuple-like variant. + /// + /// The `len` is the number of fields expected in the tuple variant. + /// + /// If the data contains a different type of variant, the following + /// `invalid_type` error should be constructed: + /// + /// ```edition2018 + /// # use serde::de::{self, value, DeserializeSeed, Visitor, VariantAccess, Unexpected}; + /// # + /// # struct X; + /// # + /// # impl<'de> VariantAccess<'de> for X { + /// # type Error = value::Error; + /// # + /// # fn unit_variant(self) -> Result<(), Self::Error> { + /// # unimplemented!() + /// # } + /// # + /// # fn newtype_variant_seed<T>(self, _: T) -> Result<T::Value, Self::Error> + /// # where + /// # T: DeserializeSeed<'de>, + /// # { unimplemented!() } + /// # + /// fn tuple_variant<V>( + /// self, + /// _len: usize, + /// _visitor: V, + /// ) -> Result<V::Value, Self::Error> + /// where + /// V: Visitor<'de>, + /// { + /// // What the data actually contained; suppose it is a unit variant. + /// let unexp = Unexpected::UnitVariant; + /// Err(de::Error::invalid_type(unexp, &"tuple variant")) + /// } + /// # + /// # fn struct_variant<V>(self, _: &[&str], _: V) -> Result<V::Value, Self::Error> + /// # where + /// # V: Visitor<'de>, + /// # { unimplemented!() } + /// # } + /// ``` + fn tuple_variant<V>(self, len: usize, visitor: V) -> Result<V::Value, Self::Error> + where + V: Visitor<'de>; + + /// Called when deserializing a struct-like variant. + /// + /// The `fields` are the names of the fields of the struct variant. + /// + /// If the data contains a different type of variant, the following + /// `invalid_type` error should be constructed: + /// + /// ```edition2018 + /// # use serde::de::{self, value, DeserializeSeed, Visitor, VariantAccess, Unexpected}; + /// # + /// # struct X; + /// # + /// # impl<'de> VariantAccess<'de> for X { + /// # type Error = value::Error; + /// # + /// # fn unit_variant(self) -> Result<(), Self::Error> { + /// # unimplemented!() + /// # } + /// # + /// # fn newtype_variant_seed<T>(self, _: T) -> Result<T::Value, Self::Error> + /// # where + /// # T: DeserializeSeed<'de>, + /// # { unimplemented!() } + /// # + /// # fn tuple_variant<V>(self, _: usize, _: V) -> Result<V::Value, Self::Error> + /// # where + /// # V: Visitor<'de>, + /// # { unimplemented!() } + /// # + /// fn struct_variant<V>( + /// self, + /// _fields: &'static [&'static str], + /// _visitor: V, + /// ) -> Result<V::Value, Self::Error> + /// where + /// V: Visitor<'de>, + /// { + /// // What the data actually contained; suppose it is a unit variant. + /// let unexp = Unexpected::UnitVariant; + /// Err(de::Error::invalid_type(unexp, &"struct variant")) + /// } + /// # } + /// ``` + fn struct_variant<V>( + self, + fields: &'static [&'static str], + visitor: V, + ) -> Result<V::Value, Self::Error> + where + V: Visitor<'de>; +} + +//////////////////////////////////////////////////////////////////////////////// + +/// Converts an existing value into a `Deserializer` from which other values can +/// be deserialized. +/// +/// # Lifetime +/// +/// The `'de` lifetime of this trait is the lifetime of data that may be +/// borrowed from the resulting `Deserializer`. See the page [Understanding +/// deserializer lifetimes] for a more detailed explanation of these lifetimes. +/// +/// [Understanding deserializer lifetimes]: https://serde.rs/lifetimes.html +/// +/// # Example +/// +/// ```edition2018 +/// use std::str::FromStr; +/// use serde::Deserialize; +/// use serde::de::{value, IntoDeserializer}; +/// +/// #[derive(Deserialize)] +/// enum Setting { +/// On, +/// Off, +/// } +/// +/// impl FromStr for Setting { +/// type Err = value::Error; +/// +/// fn from_str(s: &str) -> Result<Self, Self::Err> { +/// Self::deserialize(s.into_deserializer()) +/// } +/// } +/// ``` +pub trait IntoDeserializer<'de, E: Error = value::Error> { + /// The type of the deserializer being converted into. + type Deserializer: Deserializer<'de, Error = E>; + + /// Convert this value into a deserializer. + fn into_deserializer(self) -> Self::Deserializer; +} + +//////////////////////////////////////////////////////////////////////////////// + +/// Used in error messages. +/// +/// - expected `a` +/// - expected `a` or `b` +/// - expected one of `a`, `b`, `c` +/// +/// The slice of names must not be empty. +struct OneOf { + names: &'static [&'static str], +} + +impl Display for OneOf { + fn fmt(&self, formatter: &mut fmt::Formatter) -> fmt::Result { + match self.names.len() { + 0 => panic!(), // special case elsewhere + 1 => write!(formatter, "`{}`", self.names[0]), + 2 => write!(formatter, "`{}` or `{}`", self.names[0], self.names[1]), + _ => { + try!(write!(formatter, "one of ")); + for (i, alt) in self.names.iter().enumerate() { + if i > 0 { + try!(write!(formatter, ", ")); + } + try!(write!(formatter, "`{}`", alt)); + } + Ok(()) + } + } + } +} diff --git a/src/de/seed.rs b/src/de/seed.rs new file mode 100644 index 0000000..13b7ea4 --- /dev/null +++ b/src/de/seed.rs @@ -0,0 +1,19 @@ +use de::{Deserialize, DeserializeSeed, Deserializer}; + +/// A DeserializeSeed helper for implementing deserialize_in_place Visitors. +/// +/// Wraps a mutable reference and calls deserialize_in_place on it. +pub struct InPlaceSeed<'a, T: 'a>(pub &'a mut T); + +impl<'a, 'de, T> DeserializeSeed<'de> for InPlaceSeed<'a, T> +where + T: Deserialize<'de>, +{ + type Value = (); + fn deserialize<D>(self, deserializer: D) -> Result<Self::Value, D::Error> + where + D: Deserializer<'de>, + { + T::deserialize_in_place(deserializer, self.0) + } +} diff --git a/src/de/utf8.rs b/src/de/utf8.rs new file mode 100644 index 0000000..576fd03 --- /dev/null +++ b/src/de/utf8.rs @@ -0,0 +1,46 @@ +use lib::*; + +const TAG_CONT: u8 = 0b1000_0000; +const TAG_TWO_B: u8 = 0b1100_0000; +const TAG_THREE_B: u8 = 0b1110_0000; +const TAG_FOUR_B: u8 = 0b1111_0000; +const MAX_ONE_B: u32 = 0x80; +const MAX_TWO_B: u32 = 0x800; +const MAX_THREE_B: u32 = 0x10000; + +#[inline] +pub fn encode(c: char) -> Encode { + let code = c as u32; + let mut buf = [0; 4]; + let pos = if code < MAX_ONE_B { + buf[3] = code as u8; + 3 + } else if code < MAX_TWO_B { + buf[2] = (code >> 6 & 0x1F) as u8 | TAG_TWO_B; + buf[3] = (code & 0x3F) as u8 | TAG_CONT; + 2 + } else if code < MAX_THREE_B { + buf[1] = (code >> 12 & 0x0F) as u8 | TAG_THREE_B; + buf[2] = (code >> 6 & 0x3F) as u8 | TAG_CONT; + buf[3] = (code & 0x3F) as u8 | TAG_CONT; + 1 + } else { + buf[0] = (code >> 18 & 0x07) as u8 | TAG_FOUR_B; + buf[1] = (code >> 12 & 0x3F) as u8 | TAG_CONT; + buf[2] = (code >> 6 & 0x3F) as u8 | TAG_CONT; + buf[3] = (code & 0x3F) as u8 | TAG_CONT; + 0 + }; + Encode { buf: buf, pos: pos } +} + +pub struct Encode { + buf: [u8; 4], + pos: usize, +} + +impl Encode { + pub fn as_str(&self) -> &str { + str::from_utf8(&self.buf[self.pos..]).unwrap() + } +} diff --git a/src/de/value.rs b/src/de/value.rs new file mode 100644 index 0000000..5d88862 --- /dev/null +++ b/src/de/value.rs @@ -0,0 +1,1714 @@ +//! Building blocks for deserializing basic values using the `IntoDeserializer` +//! trait. +//! +//! ```edition2018 +//! use std::str::FromStr; +//! use serde::Deserialize; +//! use serde::de::{value, IntoDeserializer}; +//! +//! #[derive(Deserialize)] +//! enum Setting { +//! On, +//! Off, +//! } +//! +//! impl FromStr for Setting { +//! type Err = value::Error; +//! +//! fn from_str(s: &str) -> Result<Self, Self::Err> { +//! Self::deserialize(s.into_deserializer()) +//! } +//! } +//! ``` + +use lib::*; + +use self::private::{First, Second}; +use __private::size_hint; +use de::{self, Deserializer, Expected, IntoDeserializer, SeqAccess, Visitor}; +use ser; + +//////////////////////////////////////////////////////////////////////////////// + +// For structs that contain a PhantomData. We do not want the trait +// bound `E: Clone` inferred by derive(Clone). +macro_rules! impl_copy_clone { + ($ty:ident $(<$lifetime:tt>)*) => { + impl<$($lifetime,)* E> Copy for $ty<$($lifetime,)* E> {} + + impl<$($lifetime,)* E> Clone for $ty<$($lifetime,)* E> { + fn clone(&self) -> Self { + *self + } + } + }; +} + +//////////////////////////////////////////////////////////////////////////////// + +/// A minimal representation of all possible errors that can occur using the +/// `IntoDeserializer` trait. +#[derive(Clone, PartialEq)] +pub struct Error { + err: ErrorImpl, +} + +#[cfg(any(feature = "std", feature = "alloc"))] +type ErrorImpl = Box<str>; +#[cfg(not(any(feature = "std", feature = "alloc")))] +type ErrorImpl = (); + +impl de::Error for Error { + #[cfg(any(feature = "std", feature = "alloc"))] + #[cold] + fn custom<T>(msg: T) -> Self + where + T: Display, + { + Error { + err: msg.to_string().into_boxed_str(), + } + } + + #[cfg(not(any(feature = "std", feature = "alloc")))] + #[cold] + fn custom<T>(msg: T) -> Self + where + T: Display, + { + let _ = msg; + Error { err: () } + } +} + +impl ser::Error for Error { + #[cold] + fn custom<T>(msg: T) -> Self + where + T: Display, + { + de::Error::custom(msg) + } +} + +impl Display for Error { + #[cfg(any(feature = "std", feature = "alloc"))] + fn fmt(&self, formatter: &mut fmt::Formatter) -> fmt::Result { + formatter.write_str(&self.err) + } + + #[cfg(not(any(feature = "std", feature = "alloc")))] + fn fmt(&self, formatter: &mut fmt::Formatter) -> fmt::Result { + formatter.write_str("Serde deserialization error") + } +} + +impl Debug for Error { + fn fmt(&self, formatter: &mut fmt::Formatter) -> fmt::Result { + let mut debug = formatter.debug_tuple("Error"); + #[cfg(any(feature = "std", feature = "alloc"))] + debug.field(&self.err); + debug.finish() + } +} + +#[cfg(feature = "std")] +impl error::Error for Error { + fn description(&self) -> &str { + &self.err + } +} + +//////////////////////////////////////////////////////////////////////////////// + +impl<'de, E> IntoDeserializer<'de, E> for () +where + E: de::Error, +{ + type Deserializer = UnitDeserializer<E>; + + fn into_deserializer(self) -> UnitDeserializer<E> { + UnitDeserializer::new() + } +} + +/// A deserializer holding a `()`. +pub struct UnitDeserializer<E> { + marker: PhantomData<E>, +} + +impl_copy_clone!(UnitDeserializer); + +impl<E> UnitDeserializer<E> { + #[allow(missing_docs)] + pub fn new() -> Self { + UnitDeserializer { + marker: PhantomData, + } + } +} + +impl<'de, E> de::Deserializer<'de> for UnitDeserializer<E> +where + E: de::Error, +{ + type Error = E; + + forward_to_deserialize_any! { + bool i8 i16 i32 i64 i128 u8 u16 u32 u64 u128 f32 f64 char str string + bytes byte_buf unit unit_struct newtype_struct seq tuple tuple_struct + map struct enum identifier ignored_any + } + + fn deserialize_any<V>(self, visitor: V) -> Result<V::Value, Self::Error> + where + V: de::Visitor<'de>, + { + visitor.visit_unit() + } + + fn deserialize_option<V>(self, visitor: V) -> Result<V::Value, Self::Error> + where + V: de::Visitor<'de>, + { + visitor.visit_none() + } +} + +impl<E> Debug for UnitDeserializer<E> { + fn fmt(&self, formatter: &mut fmt::Formatter) -> fmt::Result { + formatter.debug_struct("UnitDeserializer").finish() + } +} + +//////////////////////////////////////////////////////////////////////////////// + +/// A deserializer that cannot be instantiated. +#[cfg(feature = "unstable")] +pub struct NeverDeserializer<E> { + never: !, + marker: PhantomData<E>, +} + +#[cfg(feature = "unstable")] +impl<'de, E> IntoDeserializer<'de, E> for ! +where + E: de::Error, +{ + type Deserializer = NeverDeserializer<E>; + + fn into_deserializer(self) -> Self::Deserializer { + self + } +} + +#[cfg(feature = "unstable")] +impl<'de, E> de::Deserializer<'de> for NeverDeserializer<E> +where + E: de::Error, +{ + type Error = E; + + fn deserialize_any<V>(self, _visitor: V) -> Result<V::Value, Self::Error> + where + V: de::Visitor<'de>, + { + self.never + } + + forward_to_deserialize_any! { + bool i8 i16 i32 i64 i128 u8 u16 u32 u64 u128 f32 f64 char str string + bytes byte_buf option unit unit_struct newtype_struct seq tuple + tuple_struct map struct enum identifier ignored_any + } +} + +//////////////////////////////////////////////////////////////////////////////// + +macro_rules! primitive_deserializer { + ($ty:ty, $doc:tt, $name:ident, $method:ident $($cast:tt)*) => { + #[doc = "A deserializer holding"] + #[doc = $doc] + pub struct $name<E> { + value: $ty, + marker: PhantomData<E> + } + + impl_copy_clone!($name); + + impl<'de, E> IntoDeserializer<'de, E> for $ty + where + E: de::Error, + { + type Deserializer = $name<E>; + + fn into_deserializer(self) -> $name<E> { + $name::new(self) + } + } + + impl<E> $name<E> { + #[allow(missing_docs)] + pub fn new(value: $ty) -> Self { + $name { + value: value, + marker: PhantomData, + } + } + } + + impl<'de, E> de::Deserializer<'de> for $name<E> + where + E: de::Error, + { + type Error = E; + + forward_to_deserialize_any! { + bool i8 i16 i32 i64 i128 u8 u16 u32 u64 u128 f32 f64 char str + string bytes byte_buf option unit unit_struct newtype_struct seq + tuple tuple_struct map struct enum identifier ignored_any + } + + fn deserialize_any<V>(self, visitor: V) -> Result<V::Value, Self::Error> + where + V: de::Visitor<'de>, + { + visitor.$method(self.value $($cast)*) + } + } + + impl<E> Debug for $name<E> { + fn fmt(&self, formatter: &mut fmt::Formatter) -> fmt::Result { + formatter + .debug_struct(stringify!($name)) + .field("value", &self.value) + .finish() + } + } + } +} + +primitive_deserializer!(bool, "a `bool`.", BoolDeserializer, visit_bool); +primitive_deserializer!(i8, "an `i8`.", I8Deserializer, visit_i8); +primitive_deserializer!(i16, "an `i16`.", I16Deserializer, visit_i16); +primitive_deserializer!(i32, "an `i32`.", I32Deserializer, visit_i32); +primitive_deserializer!(i64, "an `i64`.", I64Deserializer, visit_i64); +primitive_deserializer!(isize, "an `isize`.", IsizeDeserializer, visit_i64 as i64); +primitive_deserializer!(u8, "a `u8`.", U8Deserializer, visit_u8); +primitive_deserializer!(u16, "a `u16`.", U16Deserializer, visit_u16); +primitive_deserializer!(u64, "a `u64`.", U64Deserializer, visit_u64); +primitive_deserializer!(usize, "a `usize`.", UsizeDeserializer, visit_u64 as u64); +primitive_deserializer!(f32, "an `f32`.", F32Deserializer, visit_f32); +primitive_deserializer!(f64, "an `f64`.", F64Deserializer, visit_f64); +primitive_deserializer!(char, "a `char`.", CharDeserializer, visit_char); + +serde_if_integer128! { + primitive_deserializer!(i128, "an `i128`.", I128Deserializer, visit_i128); + primitive_deserializer!(u128, "a `u128`.", U128Deserializer, visit_u128); +} + +/// A deserializer holding a `u32`. +pub struct U32Deserializer<E> { + value: u32, + marker: PhantomData<E>, +} + +impl_copy_clone!(U32Deserializer); + +impl<'de, E> IntoDeserializer<'de, E> for u32 +where + E: de::Error, +{ + type Deserializer = U32Deserializer<E>; + + fn into_deserializer(self) -> U32Deserializer<E> { + U32Deserializer::new(self) + } +} + +impl<E> U32Deserializer<E> { + #[allow(missing_docs)] + pub fn new(value: u32) -> Self { + U32Deserializer { + value: value, + marker: PhantomData, + } + } +} + +impl<'de, E> de::Deserializer<'de> for U32Deserializer<E> +where + E: de::Error, +{ + type Error = E; + + forward_to_deserialize_any! { + bool i8 i16 i32 i64 i128 u8 u16 u32 u64 u128 f32 f64 char str string + bytes byte_buf option unit unit_struct newtype_struct seq tuple + tuple_struct map struct identifier ignored_any + } + + fn deserialize_any<V>(self, visitor: V) -> Result<V::Value, Self::Error> + where + V: de::Visitor<'de>, + { + visitor.visit_u32(self.value) + } + + fn deserialize_enum<V>( + self, + name: &str, + variants: &'static [&'static str], + visitor: V, + ) -> Result<V::Value, Self::Error> + where + V: de::Visitor<'de>, + { + let _ = name; + let _ = variants; + visitor.visit_enum(self) + } +} + +impl<'de, E> de::EnumAccess<'de> for U32Deserializer<E> +where + E: de::Error, +{ + type Error = E; + type Variant = private::UnitOnly<E>; + + fn variant_seed<T>(self, seed: T) -> Result<(T::Value, Self::Variant), Self::Error> + where + T: de::DeserializeSeed<'de>, + { + seed.deserialize(self).map(private::unit_only) + } +} + +impl<E> Debug for U32Deserializer<E> { + fn fmt(&self, formatter: &mut fmt::Formatter) -> fmt::Result { + formatter + .debug_struct("U32Deserializer") + .field("value", &self.value) + .finish() + } +} + +//////////////////////////////////////////////////////////////////////////////// + +/// A deserializer holding a `&str`. +pub struct StrDeserializer<'a, E> { + value: &'a str, + marker: PhantomData<E>, +} + +impl_copy_clone!(StrDeserializer<'de>); + +impl<'de, 'a, E> IntoDeserializer<'de, E> for &'a str +where + E: de::Error, +{ + type Deserializer = StrDeserializer<'a, E>; + + fn into_deserializer(self) -> StrDeserializer<'a, E> { + StrDeserializer::new(self) + } +} + +impl<'a, E> StrDeserializer<'a, E> { + #[allow(missing_docs)] + pub fn new(value: &'a str) -> Self { + StrDeserializer { + value: value, + marker: PhantomData, + } + } +} + +impl<'de, 'a, E> de::Deserializer<'de> for StrDeserializer<'a, E> +where + E: de::Error, +{ + type Error = E; + + fn deserialize_any<V>(self, visitor: V) -> Result<V::Value, Self::Error> + where + V: de::Visitor<'de>, + { + visitor.visit_str(self.value) + } + + fn deserialize_enum<V>( + self, + name: &str, + variants: &'static [&'static str], + visitor: V, + ) -> Result<V::Value, Self::Error> + where + V: de::Visitor<'de>, + { + let _ = name; + let _ = variants; + visitor.visit_enum(self) + } + + forward_to_deserialize_any! { + bool i8 i16 i32 i64 i128 u8 u16 u32 u64 u128 f32 f64 char str string + bytes byte_buf option unit unit_struct newtype_struct seq tuple + tuple_struct map struct identifier ignored_any + } +} + +impl<'de, 'a, E> de::EnumAccess<'de> for StrDeserializer<'a, E> +where + E: de::Error, +{ + type Error = E; + type Variant = private::UnitOnly<E>; + + fn variant_seed<T>(self, seed: T) -> Result<(T::Value, Self::Variant), Self::Error> + where + T: de::DeserializeSeed<'de>, + { + seed.deserialize(self).map(private::unit_only) + } +} + +impl<'a, E> Debug for StrDeserializer<'a, E> { + fn fmt(&self, formatter: &mut fmt::Formatter) -> fmt::Result { + formatter + .debug_struct("StrDeserializer") + .field("value", &self.value) + .finish() + } +} + +//////////////////////////////////////////////////////////////////////////////// + +/// A deserializer holding a `&str` with a lifetime tied to another +/// deserializer. +pub struct BorrowedStrDeserializer<'de, E> { + value: &'de str, + marker: PhantomData<E>, +} + +impl_copy_clone!(BorrowedStrDeserializer<'de>); + +impl<'de, E> BorrowedStrDeserializer<'de, E> { + /// Create a new borrowed deserializer from the given string. + pub fn new(value: &'de str) -> BorrowedStrDeserializer<'de, E> { + BorrowedStrDeserializer { + value: value, + marker: PhantomData, + } + } +} + +impl<'de, E> de::Deserializer<'de> for BorrowedStrDeserializer<'de, E> +where + E: de::Error, +{ + type Error = E; + + fn deserialize_any<V>(self, visitor: V) -> Result<V::Value, Self::Error> + where + V: de::Visitor<'de>, + { + visitor.visit_borrowed_str(self.value) + } + + fn deserialize_enum<V>( + self, + name: &str, + variants: &'static [&'static str], + visitor: V, + ) -> Result<V::Value, Self::Error> + where + V: de::Visitor<'de>, + { + let _ = name; + let _ = variants; + visitor.visit_enum(self) + } + + forward_to_deserialize_any! { + bool i8 i16 i32 i64 i128 u8 u16 u32 u64 u128 f32 f64 char str string + bytes byte_buf option unit unit_struct newtype_struct seq tuple + tuple_struct map struct identifier ignored_any + } +} + +impl<'de, E> de::EnumAccess<'de> for BorrowedStrDeserializer<'de, E> +where + E: de::Error, +{ + type Error = E; + type Variant = private::UnitOnly<E>; + + fn variant_seed<T>(self, seed: T) -> Result<(T::Value, Self::Variant), Self::Error> + where + T: de::DeserializeSeed<'de>, + { + seed.deserialize(self).map(private::unit_only) + } +} + +impl<'de, E> Debug for BorrowedStrDeserializer<'de, E> { + fn fmt(&self, formatter: &mut fmt::Formatter) -> fmt::Result { + formatter + .debug_struct("BorrowedStrDeserializer") + .field("value", &self.value) + .finish() + } +} + +//////////////////////////////////////////////////////////////////////////////// + +/// A deserializer holding a `String`. +#[cfg(any(feature = "std", feature = "alloc"))] +pub struct StringDeserializer<E> { + value: String, + marker: PhantomData<E>, +} + +#[cfg(any(feature = "std", feature = "alloc"))] +impl<E> Clone for StringDeserializer<E> { + fn clone(&self) -> Self { + StringDeserializer { + value: self.value.clone(), + marker: PhantomData, + } + } +} + +#[cfg(any(feature = "std", feature = "alloc"))] +impl<'de, E> IntoDeserializer<'de, E> for String +where + E: de::Error, +{ + type Deserializer = StringDeserializer<E>; + + fn into_deserializer(self) -> StringDeserializer<E> { + StringDeserializer::new(self) + } +} + +#[cfg(any(feature = "std", feature = "alloc"))] +impl<E> StringDeserializer<E> { + #[allow(missing_docs)] + pub fn new(value: String) -> Self { + StringDeserializer { + value: value, + marker: PhantomData, + } + } +} + +#[cfg(any(feature = "std", feature = "alloc"))] +impl<'de, E> de::Deserializer<'de> for StringDeserializer<E> +where + E: de::Error, +{ + type Error = E; + + fn deserialize_any<V>(self, visitor: V) -> Result<V::Value, Self::Error> + where + V: de::Visitor<'de>, + { + visitor.visit_string(self.value) + } + + fn deserialize_enum<V>( + self, + name: &str, + variants: &'static [&'static str], + visitor: V, + ) -> Result<V::Value, Self::Error> + where + V: de::Visitor<'de>, + { + let _ = name; + let _ = variants; + visitor.visit_enum(self) + } + + forward_to_deserialize_any! { + bool i8 i16 i32 i64 i128 u8 u16 u32 u64 u128 f32 f64 char str string + bytes byte_buf option unit unit_struct newtype_struct seq tuple + tuple_struct map struct identifier ignored_any + } +} + +#[cfg(any(feature = "std", feature = "alloc"))] +impl<'de, E> de::EnumAccess<'de> for StringDeserializer<E> +where + E: de::Error, +{ + type Error = E; + type Variant = private::UnitOnly<E>; + + fn variant_seed<T>(self, seed: T) -> Result<(T::Value, Self::Variant), Self::Error> + where + T: de::DeserializeSeed<'de>, + { + seed.deserialize(self).map(private::unit_only) + } +} + +#[cfg(any(feature = "std", feature = "alloc"))] +impl<E> Debug for StringDeserializer<E> { + fn fmt(&self, formatter: &mut fmt::Formatter) -> fmt::Result { + formatter + .debug_struct("StringDeserializer") + .field("value", &self.value) + .finish() + } +} + +//////////////////////////////////////////////////////////////////////////////// + +/// A deserializer holding a `Cow<str>`. +#[cfg(any(feature = "std", feature = "alloc"))] +pub struct CowStrDeserializer<'a, E> { + value: Cow<'a, str>, + marker: PhantomData<E>, +} + +#[cfg(any(feature = "std", feature = "alloc"))] +impl<'a, E> Clone for CowStrDeserializer<'a, E> { + fn clone(&self) -> Self { + CowStrDeserializer { + value: self.value.clone(), + marker: PhantomData, + } + } +} + +#[cfg(any(feature = "std", feature = "alloc"))] +impl<'de, 'a, E> IntoDeserializer<'de, E> for Cow<'a, str> +where + E: de::Error, +{ + type Deserializer = CowStrDeserializer<'a, E>; + + fn into_deserializer(self) -> CowStrDeserializer<'a, E> { + CowStrDeserializer::new(self) + } +} + +#[cfg(any(feature = "std", feature = "alloc"))] +impl<'a, E> CowStrDeserializer<'a, E> { + #[allow(missing_docs)] + pub fn new(value: Cow<'a, str>) -> Self { + CowStrDeserializer { + value: value, + marker: PhantomData, + } + } +} + +#[cfg(any(feature = "std", feature = "alloc"))] +impl<'de, 'a, E> de::Deserializer<'de> for CowStrDeserializer<'a, E> +where + E: de::Error, +{ + type Error = E; + + fn deserialize_any<V>(self, visitor: V) -> Result<V::Value, Self::Error> + where + V: de::Visitor<'de>, + { + match self.value { + Cow::Borrowed(string) => visitor.visit_str(string), + Cow::Owned(string) => visitor.visit_string(string), + } + } + + fn deserialize_enum<V>( + self, + name: &str, + variants: &'static [&'static str], + visitor: V, + ) -> Result<V::Value, Self::Error> + where + V: de::Visitor<'de>, + { + let _ = name; + let _ = variants; + visitor.visit_enum(self) + } + + forward_to_deserialize_any! { + bool i8 i16 i32 i64 i128 u8 u16 u32 u64 u128 f32 f64 char str string + bytes byte_buf option unit unit_struct newtype_struct seq tuple + tuple_struct map struct identifier ignored_any + } +} + +#[cfg(any(feature = "std", feature = "alloc"))] +impl<'de, 'a, E> de::EnumAccess<'de> for CowStrDeserializer<'a, E> +where + E: de::Error, +{ + type Error = E; + type Variant = private::UnitOnly<E>; + + fn variant_seed<T>(self, seed: T) -> Result<(T::Value, Self::Variant), Self::Error> + where + T: de::DeserializeSeed<'de>, + { + seed.deserialize(self).map(private::unit_only) + } +} + +#[cfg(any(feature = "std", feature = "alloc"))] +impl<'a, E> Debug for CowStrDeserializer<'a, E> { + fn fmt(&self, formatter: &mut fmt::Formatter) -> fmt::Result { + formatter + .debug_struct("CowStrDeserializer") + .field("value", &self.value) + .finish() + } +} + +//////////////////////////////////////////////////////////////////////////////// + +/// A deserializer holding a `&[u8]`. Always calls [`Visitor::visit_bytes`]. +pub struct BytesDeserializer<'a, E> { + value: &'a [u8], + marker: PhantomData<E>, +} + +impl<'a, E> BytesDeserializer<'a, E> { + /// Create a new deserializer from the given bytes. + pub fn new(value: &'a [u8]) -> Self { + BytesDeserializer { + value: value, + marker: PhantomData, + } + } +} + +impl_copy_clone!(BytesDeserializer<'a>); + +impl<'de, 'a, E> IntoDeserializer<'de, E> for &'a [u8] +where + E: de::Error, +{ + type Deserializer = BytesDeserializer<'a, E>; + + fn into_deserializer(self) -> BytesDeserializer<'a, E> { + BytesDeserializer::new(self) + } +} + +impl<'de, 'a, E> Deserializer<'de> for BytesDeserializer<'a, E> +where + E: de::Error, +{ + type Error = E; + + fn deserialize_any<V>(self, visitor: V) -> Result<V::Value, Self::Error> + where + V: Visitor<'de>, + { + visitor.visit_bytes(self.value) + } + + forward_to_deserialize_any! { + bool i8 i16 i32 i64 i128 u8 u16 u32 u64 u128 f32 f64 char str string + bytes byte_buf option unit unit_struct newtype_struct seq tuple + tuple_struct map struct enum identifier ignored_any + } +} + +impl<'a, E> Debug for BytesDeserializer<'a, E> { + fn fmt(&self, formatter: &mut fmt::Formatter) -> fmt::Result { + formatter + .debug_struct("BytesDeserializer") + .field("value", &self.value) + .finish() + } +} + +/// A deserializer holding a `&[u8]` with a lifetime tied to another +/// deserializer. Always calls [`Visitor::visit_borrowed_bytes`]. +pub struct BorrowedBytesDeserializer<'de, E> { + value: &'de [u8], + marker: PhantomData<E>, +} + +impl<'de, E> BorrowedBytesDeserializer<'de, E> { + /// Create a new borrowed deserializer from the given borrowed bytes. + pub fn new(value: &'de [u8]) -> Self { + BorrowedBytesDeserializer { + value: value, + marker: PhantomData, + } + } +} + +impl_copy_clone!(BorrowedBytesDeserializer<'de>); + +impl<'de, E> Deserializer<'de> for BorrowedBytesDeserializer<'de, E> +where + E: de::Error, +{ + type Error = E; + + fn deserialize_any<V>(self, visitor: V) -> Result<V::Value, Self::Error> + where + V: Visitor<'de>, + { + visitor.visit_borrowed_bytes(self.value) + } + + forward_to_deserialize_any! { + bool i8 i16 i32 i64 i128 u8 u16 u32 u64 u128 f32 f64 char str string + bytes byte_buf option unit unit_struct newtype_struct seq tuple + tuple_struct map struct enum identifier ignored_any + } +} + +impl<'de, E> Debug for BorrowedBytesDeserializer<'de, E> { + fn fmt(&self, formatter: &mut fmt::Formatter) -> fmt::Result { + formatter + .debug_struct("BorrowedBytesDeserializer") + .field("value", &self.value) + .finish() + } +} + +//////////////////////////////////////////////////////////////////////////////// + +/// A deserializer that iterates over a sequence. +#[derive(Clone)] +pub struct SeqDeserializer<I, E> { + iter: iter::Fuse<I>, + count: usize, + marker: PhantomData<E>, +} + +impl<I, E> SeqDeserializer<I, E> +where + I: Iterator, +{ + /// Construct a new `SeqDeserializer<I, E>`. + pub fn new(iter: I) -> Self { + SeqDeserializer { + iter: iter.fuse(), + count: 0, + marker: PhantomData, + } + } +} + +impl<I, E> SeqDeserializer<I, E> +where + I: Iterator, + E: de::Error, +{ + /// Check for remaining elements after passing a `SeqDeserializer` to + /// `Visitor::visit_seq`. + pub fn end(self) -> Result<(), E> { + let remaining = self.iter.count(); + if remaining == 0 { + Ok(()) + } else { + // First argument is the number of elements in the data, second + // argument is the number of elements expected by the Deserialize. + Err(de::Error::invalid_length( + self.count + remaining, + &ExpectedInSeq(self.count), + )) + } + } +} + +impl<'de, I, T, E> de::Deserializer<'de> for SeqDeserializer<I, E> +where + I: Iterator<Item = T>, + T: IntoDeserializer<'de, E>, + E: de::Error, +{ + type Error = E; + + fn deserialize_any<V>(mut self, visitor: V) -> Result<V::Value, Self::Error> + where + V: de::Visitor<'de>, + { + let v = try!(visitor.visit_seq(&mut self)); + try!(self.end()); + Ok(v) + } + + forward_to_deserialize_any! { + bool i8 i16 i32 i64 i128 u8 u16 u32 u64 u128 f32 f64 char str string + bytes byte_buf option unit unit_struct newtype_struct seq tuple + tuple_struct map struct enum identifier ignored_any + } +} + +impl<'de, I, T, E> de::SeqAccess<'de> for SeqDeserializer<I, E> +where + I: Iterator<Item = T>, + T: IntoDeserializer<'de, E>, + E: de::Error, +{ + type Error = E; + + fn next_element_seed<V>(&mut self, seed: V) -> Result<Option<V::Value>, Self::Error> + where + V: de::DeserializeSeed<'de>, + { + match self.iter.next() { + Some(value) => { + self.count += 1; + seed.deserialize(value.into_deserializer()).map(Some) + } + None => Ok(None), + } + } + + fn size_hint(&self) -> Option<usize> { + size_hint::from_bounds(&self.iter) + } +} + +struct ExpectedInSeq(usize); + +impl Expected for ExpectedInSeq { + fn fmt(&self, formatter: &mut fmt::Formatter) -> fmt::Result { + if self.0 == 1 { + write!(formatter, "1 element in sequence") + } else { + write!(formatter, "{} elements in sequence", self.0) + } + } +} + +impl<I, E> Debug for SeqDeserializer<I, E> +where + I: Debug, +{ + fn fmt(&self, formatter: &mut fmt::Formatter) -> fmt::Result { + formatter + .debug_struct("SeqDeserializer") + .field("iter", &self.iter) + .field("count", &self.count) + .finish() + } +} + +//////////////////////////////////////////////////////////////////////////////// + +#[cfg(any(feature = "std", feature = "alloc"))] +impl<'de, T, E> IntoDeserializer<'de, E> for Vec<T> +where + T: IntoDeserializer<'de, E>, + E: de::Error, +{ + type Deserializer = SeqDeserializer<<Self as IntoIterator>::IntoIter, E>; + + fn into_deserializer(self) -> Self::Deserializer { + SeqDeserializer::new(self.into_iter()) + } +} + +#[cfg(any(feature = "std", feature = "alloc"))] +impl<'de, T, E> IntoDeserializer<'de, E> for BTreeSet<T> +where + T: IntoDeserializer<'de, E> + Eq + Ord, + E: de::Error, +{ + type Deserializer = SeqDeserializer<<Self as IntoIterator>::IntoIter, E>; + + fn into_deserializer(self) -> Self::Deserializer { + SeqDeserializer::new(self.into_iter()) + } +} + +#[cfg(feature = "std")] +impl<'de, T, S, E> IntoDeserializer<'de, E> for HashSet<T, S> +where + T: IntoDeserializer<'de, E> + Eq + Hash, + S: BuildHasher, + E: de::Error, +{ + type Deserializer = SeqDeserializer<<Self as IntoIterator>::IntoIter, E>; + + fn into_deserializer(self) -> Self::Deserializer { + SeqDeserializer::new(self.into_iter()) + } +} + +//////////////////////////////////////////////////////////////////////////////// + +/// A deserializer holding a `SeqAccess`. +#[derive(Clone, Debug)] +pub struct SeqAccessDeserializer<A> { + seq: A, +} + +impl<A> SeqAccessDeserializer<A> { + /// Construct a new `SeqAccessDeserializer<A>`. + pub fn new(seq: A) -> Self { + SeqAccessDeserializer { seq: seq } + } +} + +impl<'de, A> de::Deserializer<'de> for SeqAccessDeserializer<A> +where + A: de::SeqAccess<'de>, +{ + type Error = A::Error; + + fn deserialize_any<V>(self, visitor: V) -> Result<V::Value, Self::Error> + where + V: de::Visitor<'de>, + { + visitor.visit_seq(self.seq) + } + + forward_to_deserialize_any! { + bool i8 i16 i32 i64 i128 u8 u16 u32 u64 u128 f32 f64 char str string + bytes byte_buf option unit unit_struct newtype_struct seq tuple + tuple_struct map struct enum identifier ignored_any + } +} + +//////////////////////////////////////////////////////////////////////////////// + +/// A deserializer that iterates over a map. +pub struct MapDeserializer<'de, I, E> +where + I: Iterator, + I::Item: private::Pair, +{ + iter: iter::Fuse<I>, + value: Option<Second<I::Item>>, + count: usize, + lifetime: PhantomData<&'de ()>, + error: PhantomData<E>, +} + +impl<'de, I, E> MapDeserializer<'de, I, E> +where + I: Iterator, + I::Item: private::Pair, +{ + /// Construct a new `MapDeserializer<I, E>`. + pub fn new(iter: I) -> Self { + MapDeserializer { + iter: iter.fuse(), + value: None, + count: 0, + lifetime: PhantomData, + error: PhantomData, + } + } +} + +impl<'de, I, E> MapDeserializer<'de, I, E> +where + I: Iterator, + I::Item: private::Pair, + E: de::Error, +{ + /// Check for remaining elements after passing a `MapDeserializer` to + /// `Visitor::visit_map`. + pub fn end(self) -> Result<(), E> { + let remaining = self.iter.count(); + if remaining == 0 { + Ok(()) + } else { + // First argument is the number of elements in the data, second + // argument is the number of elements expected by the Deserialize. + Err(de::Error::invalid_length( + self.count + remaining, + &ExpectedInMap(self.count), + )) + } + } +} + +impl<'de, I, E> MapDeserializer<'de, I, E> +where + I: Iterator, + I::Item: private::Pair, +{ + fn next_pair(&mut self) -> Option<(First<I::Item>, Second<I::Item>)> { + match self.iter.next() { + Some(kv) => { + self.count += 1; + Some(private::Pair::split(kv)) + } + None => None, + } + } +} + +impl<'de, I, E> de::Deserializer<'de> for MapDeserializer<'de, I, E> +where + I: Iterator, + I::Item: private::Pair, + First<I::Item>: IntoDeserializer<'de, E>, + Second<I::Item>: IntoDeserializer<'de, E>, + E: de::Error, +{ + type Error = E; + + fn deserialize_any<V>(mut self, visitor: V) -> Result<V::Value, Self::Error> + where + V: de::Visitor<'de>, + { + let value = try!(visitor.visit_map(&mut self)); + try!(self.end()); + Ok(value) + } + + fn deserialize_seq<V>(mut self, visitor: V) -> Result<V::Value, Self::Error> + where + V: de::Visitor<'de>, + { + let value = try!(visitor.visit_seq(&mut self)); + try!(self.end()); + Ok(value) + } + + fn deserialize_tuple<V>(self, len: usize, visitor: V) -> Result<V::Value, Self::Error> + where + V: de::Visitor<'de>, + { + let _ = len; + self.deserialize_seq(visitor) + } + + forward_to_deserialize_any! { + bool i8 i16 i32 i64 i128 u8 u16 u32 u64 u128 f32 f64 char str string + bytes byte_buf option unit unit_struct newtype_struct tuple_struct map + struct enum identifier ignored_any + } +} + +impl<'de, I, E> de::MapAccess<'de> for MapDeserializer<'de, I, E> +where + I: Iterator, + I::Item: private::Pair, + First<I::Item>: IntoDeserializer<'de, E>, + Second<I::Item>: IntoDeserializer<'de, E>, + E: de::Error, +{ + type Error = E; + + fn next_key_seed<T>(&mut self, seed: T) -> Result<Option<T::Value>, Self::Error> + where + T: de::DeserializeSeed<'de>, + { + match self.next_pair() { + Some((key, value)) => { + self.value = Some(value); + seed.deserialize(key.into_deserializer()).map(Some) + } + None => Ok(None), + } + } + + fn next_value_seed<T>(&mut self, seed: T) -> Result<T::Value, Self::Error> + where + T: de::DeserializeSeed<'de>, + { + let value = self.value.take(); + // Panic because this indicates a bug in the program rather than an + // expected failure. + let value = value.expect("MapAccess::next_value called before next_key"); + seed.deserialize(value.into_deserializer()) + } + + fn next_entry_seed<TK, TV>( + &mut self, + kseed: TK, + vseed: TV, + ) -> Result<Option<(TK::Value, TV::Value)>, Self::Error> + where + TK: de::DeserializeSeed<'de>, + TV: de::DeserializeSeed<'de>, + { + match self.next_pair() { + Some((key, value)) => { + let key = try!(kseed.deserialize(key.into_deserializer())); + let value = try!(vseed.deserialize(value.into_deserializer())); + Ok(Some((key, value))) + } + None => Ok(None), + } + } + + fn size_hint(&self) -> Option<usize> { + size_hint::from_bounds(&self.iter) + } +} + +impl<'de, I, E> de::SeqAccess<'de> for MapDeserializer<'de, I, E> +where + I: Iterator, + I::Item: private::Pair, + First<I::Item>: IntoDeserializer<'de, E>, + Second<I::Item>: IntoDeserializer<'de, E>, + E: de::Error, +{ + type Error = E; + + fn next_element_seed<T>(&mut self, seed: T) -> Result<Option<T::Value>, Self::Error> + where + T: de::DeserializeSeed<'de>, + { + match self.next_pair() { + Some((k, v)) => { + let de = PairDeserializer(k, v, PhantomData); + seed.deserialize(de).map(Some) + } + None => Ok(None), + } + } + + fn size_hint(&self) -> Option<usize> { + size_hint::from_bounds(&self.iter) + } +} + +// Cannot #[derive(Clone)] because of the bound `Second<I::Item>: Clone`. +impl<'de, I, E> Clone for MapDeserializer<'de, I, E> +where + I: Iterator + Clone, + I::Item: private::Pair, + Second<I::Item>: Clone, +{ + fn clone(&self) -> Self { + MapDeserializer { + iter: self.iter.clone(), + value: self.value.clone(), + count: self.count, + lifetime: self.lifetime, + error: self.error, + } + } +} + +impl<'de, I, E> Debug for MapDeserializer<'de, I, E> +where + I: Iterator + Debug, + I::Item: private::Pair, + Second<I::Item>: Debug, +{ + fn fmt(&self, formatter: &mut fmt::Formatter) -> fmt::Result { + formatter + .debug_struct("MapDeserializer") + .field("iter", &self.iter) + .field("value", &self.value) + .field("count", &self.count) + .finish() + } +} + +// Used in the `impl SeqAccess for MapDeserializer` to visit the map as a +// sequence of pairs. +struct PairDeserializer<A, B, E>(A, B, PhantomData<E>); + +impl<'de, A, B, E> de::Deserializer<'de> for PairDeserializer<A, B, E> +where + A: IntoDeserializer<'de, E>, + B: IntoDeserializer<'de, E>, + E: de::Error, +{ + type Error = E; + + forward_to_deserialize_any! { + bool i8 i16 i32 i64 i128 u8 u16 u32 u64 u128 f32 f64 char str string + bytes byte_buf option unit unit_struct newtype_struct tuple_struct map + struct enum identifier ignored_any + } + + fn deserialize_any<V>(self, visitor: V) -> Result<V::Value, Self::Error> + where + V: de::Visitor<'de>, + { + self.deserialize_seq(visitor) + } + + fn deserialize_seq<V>(self, visitor: V) -> Result<V::Value, Self::Error> + where + V: de::Visitor<'de>, + { + let mut pair_visitor = PairVisitor(Some(self.0), Some(self.1), PhantomData); + let pair = try!(visitor.visit_seq(&mut pair_visitor)); + if pair_visitor.1.is_none() { + Ok(pair) + } else { + let remaining = pair_visitor.size_hint().unwrap(); + // First argument is the number of elements in the data, second + // argument is the number of elements expected by the Deserialize. + Err(de::Error::invalid_length(2, &ExpectedInSeq(2 - remaining))) + } + } + + fn deserialize_tuple<V>(self, len: usize, visitor: V) -> Result<V::Value, Self::Error> + where + V: de::Visitor<'de>, + { + if len == 2 { + self.deserialize_seq(visitor) + } else { + // First argument is the number of elements in the data, second + // argument is the number of elements expected by the Deserialize. + Err(de::Error::invalid_length(2, &ExpectedInSeq(len))) + } + } +} + +struct PairVisitor<A, B, E>(Option<A>, Option<B>, PhantomData<E>); + +impl<'de, A, B, E> de::SeqAccess<'de> for PairVisitor<A, B, E> +where + A: IntoDeserializer<'de, E>, + B: IntoDeserializer<'de, E>, + E: de::Error, +{ + type Error = E; + + fn next_element_seed<T>(&mut self, seed: T) -> Result<Option<T::Value>, Self::Error> + where + T: de::DeserializeSeed<'de>, + { + if let Some(k) = self.0.take() { + seed.deserialize(k.into_deserializer()).map(Some) + } else if let Some(v) = self.1.take() { + seed.deserialize(v.into_deserializer()).map(Some) + } else { + Ok(None) + } + } + + fn size_hint(&self) -> Option<usize> { + if self.0.is_some() { + Some(2) + } else if self.1.is_some() { + Some(1) + } else { + Some(0) + } + } +} + +struct ExpectedInMap(usize); + +impl Expected for ExpectedInMap { + fn fmt(&self, formatter: &mut fmt::Formatter) -> fmt::Result { + if self.0 == 1 { + write!(formatter, "1 element in map") + } else { + write!(formatter, "{} elements in map", self.0) + } + } +} + +//////////////////////////////////////////////////////////////////////////////// + +#[cfg(any(feature = "std", feature = "alloc"))] +impl<'de, K, V, E> IntoDeserializer<'de, E> for BTreeMap<K, V> +where + K: IntoDeserializer<'de, E> + Eq + Ord, + V: IntoDeserializer<'de, E>, + E: de::Error, +{ + type Deserializer = MapDeserializer<'de, <Self as IntoIterator>::IntoIter, E>; + + fn into_deserializer(self) -> Self::Deserializer { + MapDeserializer::new(self.into_iter()) + } +} + +#[cfg(feature = "std")] +impl<'de, K, V, S, E> IntoDeserializer<'de, E> for HashMap<K, V, S> +where + K: IntoDeserializer<'de, E> + Eq + Hash, + V: IntoDeserializer<'de, E>, + S: BuildHasher, + E: de::Error, +{ + type Deserializer = MapDeserializer<'de, <Self as IntoIterator>::IntoIter, E>; + + fn into_deserializer(self) -> Self::Deserializer { + MapDeserializer::new(self.into_iter()) + } +} + +//////////////////////////////////////////////////////////////////////////////// + +/// A deserializer holding a `MapAccess`. +#[derive(Clone, Debug)] +pub struct MapAccessDeserializer<A> { + map: A, +} + +impl<A> MapAccessDeserializer<A> { + /// Construct a new `MapAccessDeserializer<A>`. + pub fn new(map: A) -> Self { + MapAccessDeserializer { map: map } + } +} + +impl<'de, A> de::Deserializer<'de> for MapAccessDeserializer<A> +where + A: de::MapAccess<'de>, +{ + type Error = A::Error; + + fn deserialize_any<V>(self, visitor: V) -> Result<V::Value, Self::Error> + where + V: de::Visitor<'de>, + { + visitor.visit_map(self.map) + } + + fn deserialize_enum<V>( + self, + _name: &str, + _variants: &'static [&'static str], + visitor: V, + ) -> Result<V::Value, Self::Error> + where + V: de::Visitor<'de>, + { + visitor.visit_enum(self) + } + + forward_to_deserialize_any! { + bool i8 i16 i32 i64 i128 u8 u16 u32 u64 u128 f32 f64 char str string + bytes byte_buf option unit unit_struct newtype_struct seq tuple + tuple_struct map struct identifier ignored_any + } +} + +impl<'de, A> de::EnumAccess<'de> for MapAccessDeserializer<A> +where + A: de::MapAccess<'de>, +{ + type Error = A::Error; + type Variant = private::MapAsEnum<A>; + + fn variant_seed<T>(mut self, seed: T) -> Result<(T::Value, Self::Variant), Self::Error> + where + T: de::DeserializeSeed<'de>, + { + match try!(self.map.next_key_seed(seed)) { + Some(key) => Ok((key, private::map_as_enum(self.map))), + None => Err(de::Error::invalid_type(de::Unexpected::Map, &"enum")), + } + } +} + +//////////////////////////////////////////////////////////////////////////////// + +/// A deserializer holding an `EnumAccess`. +#[derive(Clone, Debug)] +pub struct EnumAccessDeserializer<A> { + access: A, +} + +impl<A> EnumAccessDeserializer<A> { + /// Construct a new `EnumAccessDeserializer<A>`. + pub fn new(access: A) -> Self { + EnumAccessDeserializer { access: access } + } +} + +impl<'de, A> de::Deserializer<'de> for EnumAccessDeserializer<A> +where + A: de::EnumAccess<'de>, +{ + type Error = A::Error; + + fn deserialize_any<V>(self, visitor: V) -> Result<V::Value, Self::Error> + where + V: de::Visitor<'de>, + { + visitor.visit_enum(self.access) + } + + forward_to_deserialize_any! { + bool i8 i16 i32 i64 i128 u8 u16 u32 u64 u128 f32 f64 char str string + bytes byte_buf option unit unit_struct newtype_struct seq tuple + tuple_struct map struct enum identifier ignored_any + } +} + +//////////////////////////////////////////////////////////////////////////////// + +mod private { + use lib::*; + + use de::{self, DeserializeSeed, Deserializer, MapAccess, Unexpected, VariantAccess, Visitor}; + + pub struct UnitOnly<E> { + marker: PhantomData<E>, + } + + pub fn unit_only<T, E>(t: T) -> (T, UnitOnly<E>) { + ( + t, + UnitOnly { + marker: PhantomData, + }, + ) + } + + impl<'de, E> de::VariantAccess<'de> for UnitOnly<E> + where + E: de::Error, + { + type Error = E; + + fn unit_variant(self) -> Result<(), Self::Error> { + Ok(()) + } + + fn newtype_variant_seed<T>(self, _seed: T) -> Result<T::Value, Self::Error> + where + T: de::DeserializeSeed<'de>, + { + Err(de::Error::invalid_type( + Unexpected::UnitVariant, + &"newtype variant", + )) + } + + fn tuple_variant<V>(self, _len: usize, _visitor: V) -> Result<V::Value, Self::Error> + where + V: de::Visitor<'de>, + { + Err(de::Error::invalid_type( + Unexpected::UnitVariant, + &"tuple variant", + )) + } + + fn struct_variant<V>( + self, + _fields: &'static [&'static str], + _visitor: V, + ) -> Result<V::Value, Self::Error> + where + V: de::Visitor<'de>, + { + Err(de::Error::invalid_type( + Unexpected::UnitVariant, + &"struct variant", + )) + } + } + + pub struct MapAsEnum<A> { + map: A, + } + + pub fn map_as_enum<A>(map: A) -> MapAsEnum<A> { + MapAsEnum { map: map } + } + + impl<'de, A> VariantAccess<'de> for MapAsEnum<A> + where + A: MapAccess<'de>, + { + type Error = A::Error; + + fn unit_variant(mut self) -> Result<(), Self::Error> { + self.map.next_value() + } + + fn newtype_variant_seed<T>(mut self, seed: T) -> Result<T::Value, Self::Error> + where + T: DeserializeSeed<'de>, + { + self.map.next_value_seed(seed) + } + + fn tuple_variant<V>(mut self, len: usize, visitor: V) -> Result<V::Value, Self::Error> + where + V: Visitor<'de>, + { + self.map.next_value_seed(SeedTupleVariant { + len: len, + visitor: visitor, + }) + } + + fn struct_variant<V>( + mut self, + _fields: &'static [&'static str], + visitor: V, + ) -> Result<V::Value, Self::Error> + where + V: Visitor<'de>, + { + self.map + .next_value_seed(SeedStructVariant { visitor: visitor }) + } + } + + struct SeedTupleVariant<V> { + len: usize, + visitor: V, + } + + impl<'de, V> DeserializeSeed<'de> for SeedTupleVariant<V> + where + V: Visitor<'de>, + { + type Value = V::Value; + + fn deserialize<D>(self, deserializer: D) -> Result<Self::Value, D::Error> + where + D: Deserializer<'de>, + { + deserializer.deserialize_tuple(self.len, self.visitor) + } + } + + struct SeedStructVariant<V> { + visitor: V, + } + + impl<'de, V> DeserializeSeed<'de> for SeedStructVariant<V> + where + V: Visitor<'de>, + { + type Value = V::Value; + + fn deserialize<D>(self, deserializer: D) -> Result<Self::Value, D::Error> + where + D: Deserializer<'de>, + { + deserializer.deserialize_map(self.visitor) + } + } + + /// Avoid having to restate the generic types on `MapDeserializer`. The + /// `Iterator::Item` contains enough information to figure out K and V. + pub trait Pair { + type First; + type Second; + fn split(self) -> (Self::First, Self::Second); + } + + impl<A, B> Pair for (A, B) { + type First = A; + type Second = B; + fn split(self) -> (A, B) { + self + } + } + + pub type First<T> = <T as Pair>::First; + pub type Second<T> = <T as Pair>::Second; +} diff --git a/src/integer128.rs b/src/integer128.rs new file mode 100644 index 0000000..904c2a2 --- /dev/null +++ b/src/integer128.rs @@ -0,0 +1,82 @@ +/// Conditional compilation depending on whether Serde is built with support for +/// 128-bit integers. +/// +/// Data formats that wish to support Rust compiler versions older than 1.26 +/// (or targets that lack 128-bit integers) may place the i128 / u128 methods +/// of their Serializer and Deserializer behind this macro. +/// +/// Data formats that require a minimum Rust compiler version of at least 1.26, +/// or do not target platforms that lack 128-bit integers, do not need to +/// bother with this macro and may assume support for 128-bit integers. +/// +/// ```edition2018 +/// # use serde::__private::doc::Error; +/// # +/// # struct MySerializer; +/// # +/// use serde::{serde_if_integer128, Serializer}; +/// +/// impl Serializer for MySerializer { +/// type Ok = (); +/// type Error = Error; +/// +/// fn serialize_i64(self, v: i64) -> Result<Self::Ok, Self::Error> { +/// /* ... */ +/// # unimplemented!() +/// } +/// +/// /* ... */ +/// +/// serde_if_integer128! { +/// fn serialize_i128(self, v: i128) -> Result<Self::Ok, Self::Error> { +/// /* ... */ +/// # unimplemented!() +/// } +/// +/// fn serialize_u128(self, v: u128) -> Result<Self::Ok, Self::Error> { +/// /* ... */ +/// # unimplemented!() +/// } +/// } +/// # +/// # serde::__serialize_unimplemented! { +/// # bool i8 i16 i32 u8 u16 u32 u64 f32 f64 char str bytes none some +/// # unit unit_struct unit_variant newtype_struct newtype_variant seq +/// # tuple tuple_struct tuple_variant map struct struct_variant +/// # } +/// } +/// ``` +/// +/// When Serde is built with support for 128-bit integers, this macro expands +/// transparently into just the input tokens. +/// +/// ```edition2018 +/// macro_rules! serde_if_integer128 { +/// ($($tt:tt)*) => { +/// $($tt)* +/// }; +/// } +/// ``` +/// +/// When built without support for 128-bit integers, this macro expands to +/// nothing. +/// +/// ```edition2018 +/// macro_rules! serde_if_integer128 { +/// ($($tt:tt)*) => {}; +/// } +/// ``` +#[cfg(not(no_integer128))] +#[macro_export] +macro_rules! serde_if_integer128 { + ($($tt:tt)*) => { + $($tt)* + }; +} + +#[cfg(no_integer128)] +#[macro_export] +#[doc(hidden)] +macro_rules! serde_if_integer128 { + ($($tt:tt)*) => {}; +} diff --git a/src/lib.rs b/src/lib.rs new file mode 100644 index 0000000..e4bc7c8 --- /dev/null +++ b/src/lib.rs @@ -0,0 +1,334 @@ +//! # Serde +//! +//! Serde is a framework for ***ser***ializing and ***de***serializing Rust data +//! structures efficiently and generically. +//! +//! The Serde ecosystem consists of data structures that know how to serialize +//! and deserialize themselves along with data formats that know how to +//! serialize and deserialize other things. Serde provides the layer by which +//! these two groups interact with each other, allowing any supported data +//! structure to be serialized and deserialized using any supported data format. +//! +//! See the Serde website <https://serde.rs/> for additional documentation and +//! usage examples. +//! +//! ## Design +//! +//! Where many other languages rely on runtime reflection for serializing data, +//! Serde is instead built on Rust's powerful trait system. A data structure +//! that knows how to serialize and deserialize itself is one that implements +//! Serde's `Serialize` and `Deserialize` traits (or uses Serde's derive +//! attribute to automatically generate implementations at compile time). This +//! avoids any overhead of reflection or runtime type information. In fact in +//! many situations the interaction between data structure and data format can +//! be completely optimized away by the Rust compiler, leaving Serde +//! serialization to perform the same speed as a handwritten serializer for the +//! specific selection of data structure and data format. +//! +//! ## Data formats +//! +//! The following is a partial list of data formats that have been implemented +//! for Serde by the community. +//! +//! - [JSON], the ubiquitous JavaScript Object Notation used by many HTTP APIs. +//! - [Postcard], a no\_std and embedded-systems friendly compact binary format. +//! - [CBOR], a Concise Binary Object Representation designed for small message +//! size without the need for version negotiation. +//! - [YAML], a self-proclaimed human-friendly configuration language that ain't +//! markup language. +//! - [MessagePack], an efficient binary format that resembles a compact JSON. +//! - [TOML], a minimal configuration format used by [Cargo]. +//! - [Pickle], a format common in the Python world. +//! - [RON], a Rusty Object Notation. +//! - [BSON], the data storage and network transfer format used by MongoDB. +//! - [Avro], a binary format used within Apache Hadoop, with support for schema +//! definition. +//! - [JSON5], a superset of JSON including some productions from ES5. +//! - [URL] query strings, in the x-www-form-urlencoded format. +//! - [Envy], a way to deserialize environment variables into Rust structs. +//! *(deserialization only)* +//! - [Envy Store], a way to deserialize [AWS Parameter Store] parameters into +//! Rust structs. *(deserialization only)* +//! - [S-expressions], the textual representation of code and data used by the +//! Lisp language family. +//! - [D-Bus]'s binary wire format. +//! - [FlexBuffers], the schemaless cousin of Google's FlatBuffers zero-copy +//! serialization format. +//! - [Bencode], a simple binary format used in the BitTorrent protocol. +//! - [Token streams], for processing Rust procedural macro input. +//! *(deserialization only)* +//! - [DynamoDB Items], the format used by [rusoto_dynamodb] to transfer data to +//! and from DynamoDB. +//! - [Hjson], a syntax extension to JSON designed around human reading and +//! editing. *(deserialization only)* +//! +//! [JSON]: https://github.com/serde-rs/json +//! [Postcard]: https://github.com/jamesmunns/postcard +//! [CBOR]: https://github.com/enarx/ciborium +//! [YAML]: https://github.com/dtolnay/serde-yaml +//! [MessagePack]: https://github.com/3Hren/msgpack-rust +//! [TOML]: https://docs.rs/toml +//! [Pickle]: https://github.com/birkenfeld/serde-pickle +//! [RON]: https://github.com/ron-rs/ron +//! [BSON]: https://github.com/mongodb/bson-rust +//! [Avro]: https://docs.rs/apache-avro +//! [JSON5]: https://github.com/callum-oakley/json5-rs +//! [URL]: https://docs.rs/serde_qs +//! [Envy]: https://github.com/softprops/envy +//! [Envy Store]: https://github.com/softprops/envy-store +//! [Cargo]: https://doc.rust-lang.org/cargo/reference/manifest.html +//! [AWS Parameter Store]: https://docs.aws.amazon.com/systems-manager/latest/userguide/systems-manager-parameter-store.html +//! [S-expressions]: https://github.com/rotty/lexpr-rs +//! [D-Bus]: https://docs.rs/zvariant +//! [FlexBuffers]: https://github.com/google/flatbuffers/tree/master/rust/flexbuffers +//! [Bencode]: https://github.com/P3KI/bendy +//! [Token streams]: https://github.com/oxidecomputer/serde_tokenstream +//! [DynamoDB Items]: https://docs.rs/serde_dynamo +//! [rusoto_dynamodb]: https://docs.rs/rusoto_dynamodb +//! [Hjson]: https://github.com/Canop/deser-hjson + +//////////////////////////////////////////////////////////////////////////////// + +// Serde types in rustdoc of other crates get linked to here. +#![doc(html_root_url = "https://docs.rs/serde/1.0.152")] +// Support using Serde without the standard library! +#![cfg_attr(not(feature = "std"), no_std)] +// Unstable functionality only if the user asks for it. For tracking and +// discussion of these features please refer to this issue: +// +// https://github.com/serde-rs/serde/issues/812 +#![cfg_attr(feature = "unstable", feature(error_in_core, never_type))] +#![allow(unknown_lints, bare_trait_objects, deprecated)] +#![cfg_attr(feature = "cargo-clippy", allow(renamed_and_removed_lints))] +// Ignored clippy and clippy_pedantic lints +#![cfg_attr( + feature = "cargo-clippy", + allow( + // clippy bug: https://github.com/rust-lang/rust-clippy/issues/5704 + unnested_or_patterns, + // clippy bug: https://github.com/rust-lang/rust-clippy/issues/7768 + semicolon_if_nothing_returned, + // not available in our oldest supported compiler + empty_enum, + type_repetition_in_bounds, // https://github.com/rust-lang/rust-clippy/issues/8772 + // integer and float ser/de requires these sorts of casts + cast_possible_truncation, + cast_possible_wrap, + cast_sign_loss, + // things are often more readable this way + cast_lossless, + module_name_repetitions, + option_if_let_else, + single_match_else, + type_complexity, + use_self, + zero_prefixed_literal, + // correctly used + derive_partial_eq_without_eq, + enum_glob_use, + explicit_auto_deref, + map_err_ignore, + new_without_default, + result_unit_err, + wildcard_imports, + // not practical + needless_pass_by_value, + similar_names, + too_many_lines, + // preference + doc_markdown, + unseparated_literal_suffix, + // false positive + needless_doctest_main, + // noisy + missing_errors_doc, + must_use_candidate, + ) +)] +// Rustc lints. +#![deny(missing_docs, unused_imports)] + +//////////////////////////////////////////////////////////////////////////////// + +#[cfg(feature = "alloc")] +extern crate alloc; + +/// A facade around all the types we need from the `std`, `core`, and `alloc` +/// crates. This avoids elaborate import wrangling having to happen in every +/// module. +mod lib { + mod core { + #[cfg(not(feature = "std"))] + pub use core::*; + #[cfg(feature = "std")] + pub use std::*; + } + + pub use self::core::{cmp, iter, mem, num, ptr, slice, str}; + pub use self::core::{f32, f64}; + pub use self::core::{i16, i32, i64, i8, isize}; + pub use self::core::{u16, u32, u64, u8, usize}; + + pub use self::core::cell::{Cell, RefCell}; + pub use self::core::clone::{self, Clone}; + pub use self::core::convert::{self, From, Into}; + pub use self::core::default::{self, Default}; + pub use self::core::fmt::{self, Debug, Display}; + pub use self::core::marker::{self, PhantomData}; + pub use self::core::num::Wrapping; + pub use self::core::ops::Range; + pub use self::core::option::{self, Option}; + pub use self::core::result::{self, Result}; + + #[cfg(all(feature = "alloc", not(feature = "std")))] + pub use alloc::borrow::{Cow, ToOwned}; + #[cfg(feature = "std")] + pub use std::borrow::{Cow, ToOwned}; + + #[cfg(all(feature = "alloc", not(feature = "std")))] + pub use alloc::string::{String, ToString}; + #[cfg(feature = "std")] + pub use std::string::{String, ToString}; + + #[cfg(all(feature = "alloc", not(feature = "std")))] + pub use alloc::vec::Vec; + #[cfg(feature = "std")] + pub use std::vec::Vec; + + #[cfg(all(feature = "alloc", not(feature = "std")))] + pub use alloc::boxed::Box; + #[cfg(feature = "std")] + pub use std::boxed::Box; + + #[cfg(all(feature = "rc", feature = "alloc", not(feature = "std")))] + pub use alloc::rc::{Rc, Weak as RcWeak}; + #[cfg(all(feature = "rc", feature = "std"))] + pub use std::rc::{Rc, Weak as RcWeak}; + + #[cfg(all(feature = "rc", feature = "alloc", not(feature = "std")))] + pub use alloc::sync::{Arc, Weak as ArcWeak}; + #[cfg(all(feature = "rc", feature = "std"))] + pub use std::sync::{Arc, Weak as ArcWeak}; + + #[cfg(all(feature = "alloc", not(feature = "std")))] + pub use alloc::collections::{BTreeMap, BTreeSet, BinaryHeap, LinkedList, VecDeque}; + #[cfg(feature = "std")] + pub use std::collections::{BTreeMap, BTreeSet, BinaryHeap, LinkedList, VecDeque}; + + #[cfg(feature = "std")] + pub use std::{error, net}; + + #[cfg(feature = "std")] + pub use std::collections::{HashMap, HashSet}; + #[cfg(feature = "std")] + pub use std::ffi::{CStr, CString, OsStr, OsString}; + #[cfg(feature = "std")] + pub use std::hash::{BuildHasher, Hash}; + #[cfg(feature = "std")] + pub use std::io::Write; + #[cfg(feature = "std")] + pub use std::path::{Path, PathBuf}; + #[cfg(feature = "std")] + pub use std::sync::{Mutex, RwLock}; + #[cfg(feature = "std")] + pub use std::time::{SystemTime, UNIX_EPOCH}; + + #[cfg(all(feature = "std", not(no_collections_bound), no_ops_bound))] + pub use std::collections::Bound; + + #[cfg(not(no_core_reverse))] + pub use self::core::cmp::Reverse; + + #[cfg(not(no_ops_bound))] + pub use self::core::ops::Bound; + + #[cfg(not(no_range_inclusive))] + pub use self::core::ops::RangeInclusive; + + #[cfg(all(feature = "std", no_target_has_atomic, not(no_std_atomic)))] + pub use std::sync::atomic::{ + AtomicBool, AtomicI16, AtomicI32, AtomicI8, AtomicIsize, AtomicU16, AtomicU32, AtomicU8, + AtomicUsize, Ordering, + }; + #[cfg(all(feature = "std", no_target_has_atomic, not(no_std_atomic64)))] + pub use std::sync::atomic::{AtomicI64, AtomicU64}; + + #[cfg(all(feature = "std", not(no_target_has_atomic)))] + pub use std::sync::atomic::Ordering; + #[cfg(all(feature = "std", not(no_target_has_atomic), target_has_atomic = "8"))] + pub use std::sync::atomic::{AtomicBool, AtomicI8, AtomicU8}; + #[cfg(all(feature = "std", not(no_target_has_atomic), target_has_atomic = "16"))] + pub use std::sync::atomic::{AtomicI16, AtomicU16}; + #[cfg(all(feature = "std", not(no_target_has_atomic), target_has_atomic = "32"))] + pub use std::sync::atomic::{AtomicI32, AtomicU32}; + #[cfg(all(feature = "std", not(no_target_has_atomic), target_has_atomic = "64"))] + pub use std::sync::atomic::{AtomicI64, AtomicU64}; + #[cfg(all(feature = "std", not(no_target_has_atomic), target_has_atomic = "ptr"))] + pub use std::sync::atomic::{AtomicIsize, AtomicUsize}; + + #[cfg(any(feature = "std", not(no_core_duration)))] + pub use self::core::time::Duration; +} + +// None of this crate's error handling needs the `From::from` error conversion +// performed implicitly by the `?` operator or the standard library's `try!` +// macro. This simplified macro gives a 5.5% improvement in compile time +// compared to standard `try!`, and 9% improvement compared to `?`. +macro_rules! try { + ($expr:expr) => { + match $expr { + Ok(val) => val, + Err(err) => return Err(err), + } + }; +} + +//////////////////////////////////////////////////////////////////////////////// + +#[macro_use] +mod macros; + +#[macro_use] +mod integer128; + +pub mod de; +pub mod ser; + +#[doc(inline)] +pub use de::{Deserialize, Deserializer}; +#[doc(inline)] +pub use ser::{Serialize, Serializer}; + +// Used by generated code and doc tests. Not public API. +#[doc(hidden)] +#[path = "private/mod.rs"] +pub mod __private; + +#[allow(unused_imports)] +use self::__private as export; +#[allow(unused_imports)] +use self::__private as private; + +#[path = "de/seed.rs"] +mod seed; + +#[cfg(not(any(feature = "std", feature = "unstable")))] +mod std_error; + +// Re-export #[derive(Serialize, Deserialize)]. +// +// The reason re-exporting is not enabled by default is that disabling it would +// be annoying for crates that provide handwritten impls or data formats. They +// would need to disable default features and then explicitly re-enable std. +#[cfg(feature = "serde_derive")] +#[allow(unused_imports)] +#[macro_use] +extern crate serde_derive; +#[cfg(feature = "serde_derive")] +#[doc(hidden)] +pub use serde_derive::*; + +#[cfg(all(not(no_serde_derive), any(feature = "std", feature = "alloc")))] +mod actually_private { + pub struct T; +} diff --git a/src/macros.rs b/src/macros.rs new file mode 100644 index 0000000..6502a23 --- /dev/null +++ b/src/macros.rs @@ -0,0 +1,236 @@ +// Super explicit first paragraph because this shows up at the top level and +// trips up people who are just looking for basic Serialize / Deserialize +// documentation. +// +/// Helper macro when implementing the `Deserializer` part of a new data format +/// for Serde. +/// +/// Some [`Deserializer`] implementations for self-describing formats do not +/// care what hint the [`Visitor`] gives them, they just want to blindly call +/// the [`Visitor`] method corresponding to the data they can tell is in the +/// input. This requires repetitive implementations of all the [`Deserializer`] +/// trait methods. +/// +/// ```edition2018 +/// # use serde::forward_to_deserialize_any; +/// # use serde::de::{value, Deserializer, Visitor}; +/// # +/// # struct MyDeserializer; +/// # +/// # impl<'de> Deserializer<'de> for MyDeserializer { +/// # type Error = value::Error; +/// # +/// # fn deserialize_any<V>(self, _: V) -> Result<V::Value, Self::Error> +/// # where +/// # V: Visitor<'de>, +/// # { +/// # unimplemented!() +/// # } +/// # +/// #[inline] +/// fn deserialize_bool<V>(self, visitor: V) -> Result<V::Value, Self::Error> +/// where +/// V: Visitor<'de>, +/// { +/// self.deserialize_any(visitor) +/// } +/// # +/// # forward_to_deserialize_any! { +/// # i8 i16 i32 i64 i128 u8 u16 u32 u64 u128 f32 f64 char str string +/// # bytes byte_buf option unit unit_struct newtype_struct seq tuple +/// # tuple_struct map struct enum identifier ignored_any +/// # } +/// # } +/// ``` +/// +/// The `forward_to_deserialize_any!` macro implements these simple forwarding +/// methods so that they forward directly to [`Deserializer::deserialize_any`]. +/// You can choose which methods to forward. +/// +/// ```edition2018 +/// # use serde::forward_to_deserialize_any; +/// # use serde::de::{value, Deserializer, Visitor}; +/// # +/// # struct MyDeserializer; +/// # +/// impl<'de> Deserializer<'de> for MyDeserializer { +/// # type Error = value::Error; +/// # +/// fn deserialize_any<V>(self, visitor: V) -> Result<V::Value, Self::Error> +/// where +/// V: Visitor<'de>, +/// { +/// /* ... */ +/// # let _ = visitor; +/// # unimplemented!() +/// } +/// +/// forward_to_deserialize_any! { +/// bool i8 i16 i32 i64 i128 u8 u16 u32 u64 u128 f32 f64 char str string +/// bytes byte_buf option unit unit_struct newtype_struct seq tuple +/// tuple_struct map struct enum identifier ignored_any +/// } +/// } +/// ``` +/// +/// The macro assumes the convention that your `Deserializer` lifetime parameter +/// is called `'de` and that the `Visitor` type parameters on each method are +/// called `V`. A different type parameter and a different lifetime can be +/// specified explicitly if necessary. +/// +/// ```edition2018 +/// # use std::marker::PhantomData; +/// # +/// # use serde::forward_to_deserialize_any; +/// # use serde::de::{value, Deserializer, Visitor}; +/// # +/// # struct MyDeserializer<V>(PhantomData<V>); +/// # +/// # impl<'q, V> Deserializer<'q> for MyDeserializer<V> { +/// # type Error = value::Error; +/// # +/// # fn deserialize_any<W>(self, visitor: W) -> Result<W::Value, Self::Error> +/// # where +/// # W: Visitor<'q>, +/// # { +/// # unimplemented!() +/// # } +/// # +/// forward_to_deserialize_any! { +/// <W: Visitor<'q>> +/// bool i8 i16 i32 i64 i128 u8 u16 u32 u64 u128 f32 f64 char str string +/// bytes byte_buf option unit unit_struct newtype_struct seq tuple +/// tuple_struct map struct enum identifier ignored_any +/// } +/// # } +/// ``` +/// +/// [`Deserializer`]: trait.Deserializer.html +/// [`Visitor`]: de/trait.Visitor.html +/// [`Deserializer::deserialize_any`]: trait.Deserializer.html#tymethod.deserialize_any +#[macro_export(local_inner_macros)] +macro_rules! forward_to_deserialize_any { + (<$visitor:ident: Visitor<$lifetime:tt>> $($func:ident)*) => { + $(forward_to_deserialize_any_helper!{$func<$lifetime, $visitor>})* + }; + // This case must be after the previous one. + ($($func:ident)*) => { + $(forward_to_deserialize_any_helper!{$func<'de, V>})* + }; +} + +#[doc(hidden)] +#[macro_export] +macro_rules! forward_to_deserialize_any_method { + ($func:ident<$l:tt, $v:ident>($($arg:ident : $ty:ty),*)) => { + #[inline] + fn $func<$v>(self, $($arg: $ty,)* visitor: $v) -> $crate::__private::Result<$v::Value, Self::Error> + where + $v: $crate::de::Visitor<$l>, + { + $( + let _ = $arg; + )* + self.deserialize_any(visitor) + } + }; +} + +#[doc(hidden)] +#[macro_export(local_inner_macros)] +macro_rules! forward_to_deserialize_any_helper { + (bool<$l:tt, $v:ident>) => { + forward_to_deserialize_any_method!{deserialize_bool<$l, $v>()} + }; + (i8<$l:tt, $v:ident>) => { + forward_to_deserialize_any_method!{deserialize_i8<$l, $v>()} + }; + (i16<$l:tt, $v:ident>) => { + forward_to_deserialize_any_method!{deserialize_i16<$l, $v>()} + }; + (i32<$l:tt, $v:ident>) => { + forward_to_deserialize_any_method!{deserialize_i32<$l, $v>()} + }; + (i64<$l:tt, $v:ident>) => { + forward_to_deserialize_any_method!{deserialize_i64<$l, $v>()} + }; + (i128<$l:tt, $v:ident>) => { + serde_if_integer128! { + forward_to_deserialize_any_method!{deserialize_i128<$l, $v>()} + } + }; + (u8<$l:tt, $v:ident>) => { + forward_to_deserialize_any_method!{deserialize_u8<$l, $v>()} + }; + (u16<$l:tt, $v:ident>) => { + forward_to_deserialize_any_method!{deserialize_u16<$l, $v>()} + }; + (u32<$l:tt, $v:ident>) => { + forward_to_deserialize_any_method!{deserialize_u32<$l, $v>()} + }; + (u64<$l:tt, $v:ident>) => { + forward_to_deserialize_any_method!{deserialize_u64<$l, $v>()} + }; + (u128<$l:tt, $v:ident>) => { + serde_if_integer128! { + forward_to_deserialize_any_method!{deserialize_u128<$l, $v>()} + } + }; + (f32<$l:tt, $v:ident>) => { + forward_to_deserialize_any_method!{deserialize_f32<$l, $v>()} + }; + (f64<$l:tt, $v:ident>) => { + forward_to_deserialize_any_method!{deserialize_f64<$l, $v>()} + }; + (char<$l:tt, $v:ident>) => { + forward_to_deserialize_any_method!{deserialize_char<$l, $v>()} + }; + (str<$l:tt, $v:ident>) => { + forward_to_deserialize_any_method!{deserialize_str<$l, $v>()} + }; + (string<$l:tt, $v:ident>) => { + forward_to_deserialize_any_method!{deserialize_string<$l, $v>()} + }; + (bytes<$l:tt, $v:ident>) => { + forward_to_deserialize_any_method!{deserialize_bytes<$l, $v>()} + }; + (byte_buf<$l:tt, $v:ident>) => { + forward_to_deserialize_any_method!{deserialize_byte_buf<$l, $v>()} + }; + (option<$l:tt, $v:ident>) => { + forward_to_deserialize_any_method!{deserialize_option<$l, $v>()} + }; + (unit<$l:tt, $v:ident>) => { + forward_to_deserialize_any_method!{deserialize_unit<$l, $v>()} + }; + (unit_struct<$l:tt, $v:ident>) => { + forward_to_deserialize_any_method!{deserialize_unit_struct<$l, $v>(name: &'static str)} + }; + (newtype_struct<$l:tt, $v:ident>) => { + forward_to_deserialize_any_method!{deserialize_newtype_struct<$l, $v>(name: &'static str)} + }; + (seq<$l:tt, $v:ident>) => { + forward_to_deserialize_any_method!{deserialize_seq<$l, $v>()} + }; + (tuple<$l:tt, $v:ident>) => { + forward_to_deserialize_any_method!{deserialize_tuple<$l, $v>(len: usize)} + }; + (tuple_struct<$l:tt, $v:ident>) => { + forward_to_deserialize_any_method!{deserialize_tuple_struct<$l, $v>(name: &'static str, len: usize)} + }; + (map<$l:tt, $v:ident>) => { + forward_to_deserialize_any_method!{deserialize_map<$l, $v>()} + }; + (struct<$l:tt, $v:ident>) => { + forward_to_deserialize_any_method!{deserialize_struct<$l, $v>(name: &'static str, fields: &'static [&'static str])} + }; + (enum<$l:tt, $v:ident>) => { + forward_to_deserialize_any_method!{deserialize_enum<$l, $v>(name: &'static str, variants: &'static [&'static str])} + }; + (identifier<$l:tt, $v:ident>) => { + forward_to_deserialize_any_method!{deserialize_identifier<$l, $v>()} + }; + (ignored_any<$l:tt, $v:ident>) => { + forward_to_deserialize_any_method!{deserialize_ignored_any<$l, $v>()} + }; +} diff --git a/src/private/de.rs b/src/private/de.rs new file mode 100644 index 0000000..e9c693d --- /dev/null +++ b/src/private/de.rs @@ -0,0 +1,2995 @@ +use lib::*; + +use de::value::{BorrowedBytesDeserializer, BytesDeserializer}; +use de::{Deserialize, Deserializer, Error, IntoDeserializer, Visitor}; + +#[cfg(any(feature = "std", feature = "alloc"))] +use de::{DeserializeSeed, MapAccess, Unexpected}; + +#[cfg(any(feature = "std", feature = "alloc"))] +pub use self::content::{ + Content, ContentDeserializer, ContentRefDeserializer, EnumDeserializer, + InternallyTaggedUnitVisitor, TagContentOtherField, TagContentOtherFieldVisitor, + TagOrContentField, TagOrContentFieldVisitor, TaggedContentVisitor, UntaggedUnitVisitor, +}; + +pub use seed::InPlaceSeed; + +/// If the missing field is of type `Option<T>` then treat is as `None`, +/// otherwise it is an error. +pub fn missing_field<'de, V, E>(field: &'static str) -> Result<V, E> +where + V: Deserialize<'de>, + E: Error, +{ + struct MissingFieldDeserializer<E>(&'static str, PhantomData<E>); + + impl<'de, E> Deserializer<'de> for MissingFieldDeserializer<E> + where + E: Error, + { + type Error = E; + + fn deserialize_any<V>(self, _visitor: V) -> Result<V::Value, E> + where + V: Visitor<'de>, + { + Err(Error::missing_field(self.0)) + } + + fn deserialize_option<V>(self, visitor: V) -> Result<V::Value, E> + where + V: Visitor<'de>, + { + visitor.visit_none() + } + + forward_to_deserialize_any! { + bool i8 i16 i32 i64 i128 u8 u16 u32 u64 u128 f32 f64 char str string + bytes byte_buf unit unit_struct newtype_struct seq tuple + tuple_struct map struct enum identifier ignored_any + } + } + + let deserializer = MissingFieldDeserializer(field, PhantomData); + Deserialize::deserialize(deserializer) +} + +#[cfg(any(feature = "std", feature = "alloc"))] +pub fn borrow_cow_str<'de: 'a, 'a, D, R>(deserializer: D) -> Result<R, D::Error> +where + D: Deserializer<'de>, + R: From<Cow<'a, str>>, +{ + struct CowStrVisitor; + + impl<'a> Visitor<'a> for CowStrVisitor { + type Value = Cow<'a, str>; + + fn expecting(&self, formatter: &mut fmt::Formatter) -> fmt::Result { + formatter.write_str("a string") + } + + fn visit_str<E>(self, v: &str) -> Result<Self::Value, E> + where + E: Error, + { + Ok(Cow::Owned(v.to_owned())) + } + + fn visit_borrowed_str<E>(self, v: &'a str) -> Result<Self::Value, E> + where + E: Error, + { + Ok(Cow::Borrowed(v)) + } + + fn visit_string<E>(self, v: String) -> Result<Self::Value, E> + where + E: Error, + { + Ok(Cow::Owned(v)) + } + + fn visit_bytes<E>(self, v: &[u8]) -> Result<Self::Value, E> + where + E: Error, + { + match str::from_utf8(v) { + Ok(s) => Ok(Cow::Owned(s.to_owned())), + Err(_) => Err(Error::invalid_value(Unexpected::Bytes(v), &self)), + } + } + + fn visit_borrowed_bytes<E>(self, v: &'a [u8]) -> Result<Self::Value, E> + where + E: Error, + { + match str::from_utf8(v) { + Ok(s) => Ok(Cow::Borrowed(s)), + Err(_) => Err(Error::invalid_value(Unexpected::Bytes(v), &self)), + } + } + + fn visit_byte_buf<E>(self, v: Vec<u8>) -> Result<Self::Value, E> + where + E: Error, + { + match String::from_utf8(v) { + Ok(s) => Ok(Cow::Owned(s)), + Err(e) => Err(Error::invalid_value( + Unexpected::Bytes(&e.into_bytes()), + &self, + )), + } + } + } + + deserializer.deserialize_str(CowStrVisitor).map(From::from) +} + +#[cfg(any(feature = "std", feature = "alloc"))] +pub fn borrow_cow_bytes<'de: 'a, 'a, D, R>(deserializer: D) -> Result<R, D::Error> +where + D: Deserializer<'de>, + R: From<Cow<'a, [u8]>>, +{ + struct CowBytesVisitor; + + impl<'a> Visitor<'a> for CowBytesVisitor { + type Value = Cow<'a, [u8]>; + + fn expecting(&self, formatter: &mut fmt::Formatter) -> fmt::Result { + formatter.write_str("a byte array") + } + + fn visit_str<E>(self, v: &str) -> Result<Self::Value, E> + where + E: Error, + { + Ok(Cow::Owned(v.as_bytes().to_vec())) + } + + fn visit_borrowed_str<E>(self, v: &'a str) -> Result<Self::Value, E> + where + E: Error, + { + Ok(Cow::Borrowed(v.as_bytes())) + } + + fn visit_string<E>(self, v: String) -> Result<Self::Value, E> + where + E: Error, + { + Ok(Cow::Owned(v.into_bytes())) + } + + fn visit_bytes<E>(self, v: &[u8]) -> Result<Self::Value, E> + where + E: Error, + { + Ok(Cow::Owned(v.to_vec())) + } + + fn visit_borrowed_bytes<E>(self, v: &'a [u8]) -> Result<Self::Value, E> + where + E: Error, + { + Ok(Cow::Borrowed(v)) + } + + fn visit_byte_buf<E>(self, v: Vec<u8>) -> Result<Self::Value, E> + where + E: Error, + { + Ok(Cow::Owned(v)) + } + } + + deserializer + .deserialize_bytes(CowBytesVisitor) + .map(From::from) +} + +#[cfg(any(feature = "std", feature = "alloc"))] +mod content { + // This module is private and nothing here should be used outside of + // generated code. + // + // We will iterate on the implementation for a few releases and only have to + // worry about backward compatibility for the `untagged` and `tag` attributes + // rather than for this entire mechanism. + // + // This issue is tracking making some of this stuff public: + // https://github.com/serde-rs/serde/issues/741 + + use lib::*; + + use __private::size_hint; + use actually_private; + use de::{ + self, Deserialize, DeserializeSeed, Deserializer, EnumAccess, Expected, IgnoredAny, + MapAccess, SeqAccess, Unexpected, Visitor, + }; + + /// Used from generated code to buffer the contents of the Deserializer when + /// deserializing untagged enums and internally tagged enums. + /// + /// Not public API. Use serde-value instead. + #[derive(Debug, Clone)] + pub enum Content<'de> { + Bool(bool), + + U8(u8), + U16(u16), + U32(u32), + U64(u64), + + I8(i8), + I16(i16), + I32(i32), + I64(i64), + + F32(f32), + F64(f64), + + Char(char), + String(String), + Str(&'de str), + ByteBuf(Vec<u8>), + Bytes(&'de [u8]), + + None, + Some(Box<Content<'de>>), + + Unit, + Newtype(Box<Content<'de>>), + Seq(Vec<Content<'de>>), + Map(Vec<(Content<'de>, Content<'de>)>), + } + + impl<'de> Content<'de> { + pub fn as_str(&self) -> Option<&str> { + match *self { + Content::Str(x) => Some(x), + Content::String(ref x) => Some(x), + Content::Bytes(x) => str::from_utf8(x).ok(), + Content::ByteBuf(ref x) => str::from_utf8(x).ok(), + _ => None, + } + } + + #[cold] + fn unexpected(&self) -> Unexpected { + match *self { + Content::Bool(b) => Unexpected::Bool(b), + Content::U8(n) => Unexpected::Unsigned(n as u64), + Content::U16(n) => Unexpected::Unsigned(n as u64), + Content::U32(n) => Unexpected::Unsigned(n as u64), + Content::U64(n) => Unexpected::Unsigned(n), + Content::I8(n) => Unexpected::Signed(n as i64), + Content::I16(n) => Unexpected::Signed(n as i64), + Content::I32(n) => Unexpected::Signed(n as i64), + Content::I64(n) => Unexpected::Signed(n), + Content::F32(f) => Unexpected::Float(f as f64), + Content::F64(f) => Unexpected::Float(f), + Content::Char(c) => Unexpected::Char(c), + Content::String(ref s) => Unexpected::Str(s), + Content::Str(s) => Unexpected::Str(s), + Content::ByteBuf(ref b) => Unexpected::Bytes(b), + Content::Bytes(b) => Unexpected::Bytes(b), + Content::None | Content::Some(_) => Unexpected::Option, + Content::Unit => Unexpected::Unit, + Content::Newtype(_) => Unexpected::NewtypeStruct, + Content::Seq(_) => Unexpected::Seq, + Content::Map(_) => Unexpected::Map, + } + } + } + + impl<'de> Deserialize<'de> for Content<'de> { + fn deserialize<D>(deserializer: D) -> Result<Self, D::Error> + where + D: Deserializer<'de>, + { + // Untagged and internally tagged enums are only supported in + // self-describing formats. + let visitor = ContentVisitor { value: PhantomData }; + deserializer.__deserialize_content(actually_private::T, visitor) + } + } + + struct ContentVisitor<'de> { + value: PhantomData<Content<'de>>, + } + + impl<'de> ContentVisitor<'de> { + fn new() -> Self { + ContentVisitor { value: PhantomData } + } + } + + impl<'de> Visitor<'de> for ContentVisitor<'de> { + type Value = Content<'de>; + + fn expecting(&self, fmt: &mut fmt::Formatter) -> fmt::Result { + fmt.write_str("any value") + } + + fn visit_bool<F>(self, value: bool) -> Result<Self::Value, F> + where + F: de::Error, + { + Ok(Content::Bool(value)) + } + + fn visit_i8<F>(self, value: i8) -> Result<Self::Value, F> + where + F: de::Error, + { + Ok(Content::I8(value)) + } + + fn visit_i16<F>(self, value: i16) -> Result<Self::Value, F> + where + F: de::Error, + { + Ok(Content::I16(value)) + } + + fn visit_i32<F>(self, value: i32) -> Result<Self::Value, F> + where + F: de::Error, + { + Ok(Content::I32(value)) + } + + fn visit_i64<F>(self, value: i64) -> Result<Self::Value, F> + where + F: de::Error, + { + Ok(Content::I64(value)) + } + + fn visit_u8<F>(self, value: u8) -> Result<Self::Value, F> + where + F: de::Error, + { + Ok(Content::U8(value)) + } + + fn visit_u16<F>(self, value: u16) -> Result<Self::Value, F> + where + F: de::Error, + { + Ok(Content::U16(value)) + } + + fn visit_u32<F>(self, value: u32) -> Result<Self::Value, F> + where + F: de::Error, + { + Ok(Content::U32(value)) + } + + fn visit_u64<F>(self, value: u64) -> Result<Self::Value, F> + where + F: de::Error, + { + Ok(Content::U64(value)) + } + + fn visit_f32<F>(self, value: f32) -> Result<Self::Value, F> + where + F: de::Error, + { + Ok(Content::F32(value)) + } + + fn visit_f64<F>(self, value: f64) -> Result<Self::Value, F> + where + F: de::Error, + { + Ok(Content::F64(value)) + } + + fn visit_char<F>(self, value: char) -> Result<Self::Value, F> + where + F: de::Error, + { + Ok(Content::Char(value)) + } + + fn visit_str<F>(self, value: &str) -> Result<Self::Value, F> + where + F: de::Error, + { + Ok(Content::String(value.into())) + } + + fn visit_borrowed_str<F>(self, value: &'de str) -> Result<Self::Value, F> + where + F: de::Error, + { + Ok(Content::Str(value)) + } + + fn visit_string<F>(self, value: String) -> Result<Self::Value, F> + where + F: de::Error, + { + Ok(Content::String(value)) + } + + fn visit_bytes<F>(self, value: &[u8]) -> Result<Self::Value, F> + where + F: de::Error, + { + Ok(Content::ByteBuf(value.into())) + } + + fn visit_borrowed_bytes<F>(self, value: &'de [u8]) -> Result<Self::Value, F> + where + F: de::Error, + { + Ok(Content::Bytes(value)) + } + + fn visit_byte_buf<F>(self, value: Vec<u8>) -> Result<Self::Value, F> + where + F: de::Error, + { + Ok(Content::ByteBuf(value)) + } + + fn visit_unit<F>(self) -> Result<Self::Value, F> + where + F: de::Error, + { + Ok(Content::Unit) + } + + fn visit_none<F>(self) -> Result<Self::Value, F> + where + F: de::Error, + { + Ok(Content::None) + } + + fn visit_some<D>(self, deserializer: D) -> Result<Self::Value, D::Error> + where + D: Deserializer<'de>, + { + Deserialize::deserialize(deserializer).map(|v| Content::Some(Box::new(v))) + } + + fn visit_newtype_struct<D>(self, deserializer: D) -> Result<Self::Value, D::Error> + where + D: Deserializer<'de>, + { + Deserialize::deserialize(deserializer).map(|v| Content::Newtype(Box::new(v))) + } + + fn visit_seq<V>(self, mut visitor: V) -> Result<Self::Value, V::Error> + where + V: SeqAccess<'de>, + { + let mut vec = Vec::with_capacity(size_hint::cautious(visitor.size_hint())); + while let Some(e) = try!(visitor.next_element()) { + vec.push(e); + } + Ok(Content::Seq(vec)) + } + + fn visit_map<V>(self, mut visitor: V) -> Result<Self::Value, V::Error> + where + V: MapAccess<'de>, + { + let mut vec = Vec::with_capacity(size_hint::cautious(visitor.size_hint())); + while let Some(kv) = try!(visitor.next_entry()) { + vec.push(kv); + } + Ok(Content::Map(vec)) + } + + fn visit_enum<V>(self, _visitor: V) -> Result<Self::Value, V::Error> + where + V: EnumAccess<'de>, + { + Err(de::Error::custom( + "untagged and internally tagged enums do not support enum input", + )) + } + } + + /// This is the type of the map keys in an internally tagged enum. + /// + /// Not public API. + pub enum TagOrContent<'de> { + Tag, + Content(Content<'de>), + } + + struct TagOrContentVisitor<'de> { + name: &'static str, + value: PhantomData<TagOrContent<'de>>, + } + + impl<'de> TagOrContentVisitor<'de> { + fn new(name: &'static str) -> Self { + TagOrContentVisitor { + name: name, + value: PhantomData, + } + } + } + + impl<'de> DeserializeSeed<'de> for TagOrContentVisitor<'de> { + type Value = TagOrContent<'de>; + + fn deserialize<D>(self, deserializer: D) -> Result<Self::Value, D::Error> + where + D: Deserializer<'de>, + { + // Internally tagged enums are only supported in self-describing + // formats. + deserializer.deserialize_any(self) + } + } + + impl<'de> Visitor<'de> for TagOrContentVisitor<'de> { + type Value = TagOrContent<'de>; + + fn expecting(&self, fmt: &mut fmt::Formatter) -> fmt::Result { + write!(fmt, "a type tag `{}` or any other value", self.name) + } + + fn visit_bool<F>(self, value: bool) -> Result<Self::Value, F> + where + F: de::Error, + { + ContentVisitor::new() + .visit_bool(value) + .map(TagOrContent::Content) + } + + fn visit_i8<F>(self, value: i8) -> Result<Self::Value, F> + where + F: de::Error, + { + ContentVisitor::new() + .visit_i8(value) + .map(TagOrContent::Content) + } + + fn visit_i16<F>(self, value: i16) -> Result<Self::Value, F> + where + F: de::Error, + { + ContentVisitor::new() + .visit_i16(value) + .map(TagOrContent::Content) + } + + fn visit_i32<F>(self, value: i32) -> Result<Self::Value, F> + where + F: de::Error, + { + ContentVisitor::new() + .visit_i32(value) + .map(TagOrContent::Content) + } + + fn visit_i64<F>(self, value: i64) -> Result<Self::Value, F> + where + F: de::Error, + { + ContentVisitor::new() + .visit_i64(value) + .map(TagOrContent::Content) + } + + fn visit_u8<F>(self, value: u8) -> Result<Self::Value, F> + where + F: de::Error, + { + ContentVisitor::new() + .visit_u8(value) + .map(TagOrContent::Content) + } + + fn visit_u16<F>(self, value: u16) -> Result<Self::Value, F> + where + F: de::Error, + { + ContentVisitor::new() + .visit_u16(value) + .map(TagOrContent::Content) + } + + fn visit_u32<F>(self, value: u32) -> Result<Self::Value, F> + where + F: de::Error, + { + ContentVisitor::new() + .visit_u32(value) + .map(TagOrContent::Content) + } + + fn visit_u64<F>(self, value: u64) -> Result<Self::Value, F> + where + F: de::Error, + { + ContentVisitor::new() + .visit_u64(value) + .map(TagOrContent::Content) + } + + fn visit_f32<F>(self, value: f32) -> Result<Self::Value, F> + where + F: de::Error, + { + ContentVisitor::new() + .visit_f32(value) + .map(TagOrContent::Content) + } + + fn visit_f64<F>(self, value: f64) -> Result<Self::Value, F> + where + F: de::Error, + { + ContentVisitor::new() + .visit_f64(value) + .map(TagOrContent::Content) + } + + fn visit_char<F>(self, value: char) -> Result<Self::Value, F> + where + F: de::Error, + { + ContentVisitor::new() + .visit_char(value) + .map(TagOrContent::Content) + } + + fn visit_str<F>(self, value: &str) -> Result<Self::Value, F> + where + F: de::Error, + { + if value == self.name { + Ok(TagOrContent::Tag) + } else { + ContentVisitor::new() + .visit_str(value) + .map(TagOrContent::Content) + } + } + + fn visit_borrowed_str<F>(self, value: &'de str) -> Result<Self::Value, F> + where + F: de::Error, + { + if value == self.name { + Ok(TagOrContent::Tag) + } else { + ContentVisitor::new() + .visit_borrowed_str(value) + .map(TagOrContent::Content) + } + } + + fn visit_string<F>(self, value: String) -> Result<Self::Value, F> + where + F: de::Error, + { + if value == self.name { + Ok(TagOrContent::Tag) + } else { + ContentVisitor::new() + .visit_string(value) + .map(TagOrContent::Content) + } + } + + fn visit_bytes<F>(self, value: &[u8]) -> Result<Self::Value, F> + where + F: de::Error, + { + if value == self.name.as_bytes() { + Ok(TagOrContent::Tag) + } else { + ContentVisitor::new() + .visit_bytes(value) + .map(TagOrContent::Content) + } + } + + fn visit_borrowed_bytes<F>(self, value: &'de [u8]) -> Result<Self::Value, F> + where + F: de::Error, + { + if value == self.name.as_bytes() { + Ok(TagOrContent::Tag) + } else { + ContentVisitor::new() + .visit_borrowed_bytes(value) + .map(TagOrContent::Content) + } + } + + fn visit_byte_buf<F>(self, value: Vec<u8>) -> Result<Self::Value, F> + where + F: de::Error, + { + if value == self.name.as_bytes() { + Ok(TagOrContent::Tag) + } else { + ContentVisitor::new() + .visit_byte_buf(value) + .map(TagOrContent::Content) + } + } + + fn visit_unit<F>(self) -> Result<Self::Value, F> + where + F: de::Error, + { + ContentVisitor::new() + .visit_unit() + .map(TagOrContent::Content) + } + + fn visit_none<F>(self) -> Result<Self::Value, F> + where + F: de::Error, + { + ContentVisitor::new() + .visit_none() + .map(TagOrContent::Content) + } + + fn visit_some<D>(self, deserializer: D) -> Result<Self::Value, D::Error> + where + D: Deserializer<'de>, + { + ContentVisitor::new() + .visit_some(deserializer) + .map(TagOrContent::Content) + } + + fn visit_newtype_struct<D>(self, deserializer: D) -> Result<Self::Value, D::Error> + where + D: Deserializer<'de>, + { + ContentVisitor::new() + .visit_newtype_struct(deserializer) + .map(TagOrContent::Content) + } + + fn visit_seq<V>(self, visitor: V) -> Result<Self::Value, V::Error> + where + V: SeqAccess<'de>, + { + ContentVisitor::new() + .visit_seq(visitor) + .map(TagOrContent::Content) + } + + fn visit_map<V>(self, visitor: V) -> Result<Self::Value, V::Error> + where + V: MapAccess<'de>, + { + ContentVisitor::new() + .visit_map(visitor) + .map(TagOrContent::Content) + } + + fn visit_enum<V>(self, visitor: V) -> Result<Self::Value, V::Error> + where + V: EnumAccess<'de>, + { + ContentVisitor::new() + .visit_enum(visitor) + .map(TagOrContent::Content) + } + } + + /// Used by generated code to deserialize an internally tagged enum. + /// + /// Not public API. + pub struct TaggedContent<'de, T> { + pub tag: T, + pub content: Content<'de>, + } + + /// Not public API. + pub struct TaggedContentVisitor<'de, T> { + tag_name: &'static str, + expecting: &'static str, + value: PhantomData<TaggedContent<'de, T>>, + } + + impl<'de, T> TaggedContentVisitor<'de, T> { + /// Visitor for the content of an internally tagged enum with the given + /// tag name. + pub fn new(name: &'static str, expecting: &'static str) -> Self { + TaggedContentVisitor { + tag_name: name, + expecting: expecting, + value: PhantomData, + } + } + } + + impl<'de, T> DeserializeSeed<'de> for TaggedContentVisitor<'de, T> + where + T: Deserialize<'de>, + { + type Value = TaggedContent<'de, T>; + + fn deserialize<D>(self, deserializer: D) -> Result<Self::Value, D::Error> + where + D: Deserializer<'de>, + { + // Internally tagged enums are only supported in self-describing + // formats. + deserializer.deserialize_any(self) + } + } + + impl<'de, T> Visitor<'de> for TaggedContentVisitor<'de, T> + where + T: Deserialize<'de>, + { + type Value = TaggedContent<'de, T>; + + fn expecting(&self, fmt: &mut fmt::Formatter) -> fmt::Result { + fmt.write_str(self.expecting) + } + + fn visit_seq<S>(self, mut seq: S) -> Result<Self::Value, S::Error> + where + S: SeqAccess<'de>, + { + let tag = match try!(seq.next_element()) { + Some(tag) => tag, + None => { + return Err(de::Error::missing_field(self.tag_name)); + } + }; + let rest = de::value::SeqAccessDeserializer::new(seq); + Ok(TaggedContent { + tag: tag, + content: try!(Content::deserialize(rest)), + }) + } + + fn visit_map<M>(self, mut map: M) -> Result<Self::Value, M::Error> + where + M: MapAccess<'de>, + { + let mut tag = None; + let mut vec = Vec::with_capacity(size_hint::cautious(map.size_hint())); + while let Some(k) = try!(map.next_key_seed(TagOrContentVisitor::new(self.tag_name))) { + match k { + TagOrContent::Tag => { + if tag.is_some() { + return Err(de::Error::duplicate_field(self.tag_name)); + } + tag = Some(try!(map.next_value())); + } + TagOrContent::Content(k) => { + let v = try!(map.next_value()); + vec.push((k, v)); + } + } + } + match tag { + None => Err(de::Error::missing_field(self.tag_name)), + Some(tag) => Ok(TaggedContent { + tag: tag, + content: Content::Map(vec), + }), + } + } + } + + /// Used by generated code to deserialize an adjacently tagged enum. + /// + /// Not public API. + pub enum TagOrContentField { + Tag, + Content, + } + + /// Not public API. + pub struct TagOrContentFieldVisitor { + pub tag: &'static str, + pub content: &'static str, + } + + impl<'de> DeserializeSeed<'de> for TagOrContentFieldVisitor { + type Value = TagOrContentField; + + fn deserialize<D>(self, deserializer: D) -> Result<Self::Value, D::Error> + where + D: Deserializer<'de>, + { + deserializer.deserialize_str(self) + } + } + + impl<'de> Visitor<'de> for TagOrContentFieldVisitor { + type Value = TagOrContentField; + + fn expecting(&self, formatter: &mut fmt::Formatter) -> fmt::Result { + write!(formatter, "{:?} or {:?}", self.tag, self.content) + } + + fn visit_str<E>(self, field: &str) -> Result<Self::Value, E> + where + E: de::Error, + { + if field == self.tag { + Ok(TagOrContentField::Tag) + } else if field == self.content { + Ok(TagOrContentField::Content) + } else { + Err(de::Error::invalid_value(Unexpected::Str(field), &self)) + } + } + } + + /// Used by generated code to deserialize an adjacently tagged enum when + /// ignoring unrelated fields is allowed. + /// + /// Not public API. + pub enum TagContentOtherField { + Tag, + Content, + Other, + } + + /// Not public API. + pub struct TagContentOtherFieldVisitor { + pub tag: &'static str, + pub content: &'static str, + } + + impl<'de> DeserializeSeed<'de> for TagContentOtherFieldVisitor { + type Value = TagContentOtherField; + + fn deserialize<D>(self, deserializer: D) -> Result<Self::Value, D::Error> + where + D: Deserializer<'de>, + { + deserializer.deserialize_str(self) + } + } + + impl<'de> Visitor<'de> for TagContentOtherFieldVisitor { + type Value = TagContentOtherField; + + fn expecting(&self, formatter: &mut fmt::Formatter) -> fmt::Result { + write!( + formatter, + "{:?}, {:?}, or other ignored fields", + self.tag, self.content + ) + } + + fn visit_str<E>(self, field: &str) -> Result<Self::Value, E> + where + E: de::Error, + { + if field == self.tag { + Ok(TagContentOtherField::Tag) + } else if field == self.content { + Ok(TagContentOtherField::Content) + } else { + Ok(TagContentOtherField::Other) + } + } + } + + /// Not public API + pub struct ContentDeserializer<'de, E> { + content: Content<'de>, + err: PhantomData<E>, + } + + impl<'de, E> ContentDeserializer<'de, E> + where + E: de::Error, + { + #[cold] + fn invalid_type(self, exp: &Expected) -> E { + de::Error::invalid_type(self.content.unexpected(), exp) + } + + fn deserialize_integer<V>(self, visitor: V) -> Result<V::Value, E> + where + V: Visitor<'de>, + { + match self.content { + Content::U8(v) => visitor.visit_u8(v), + Content::U16(v) => visitor.visit_u16(v), + Content::U32(v) => visitor.visit_u32(v), + Content::U64(v) => visitor.visit_u64(v), + Content::I8(v) => visitor.visit_i8(v), + Content::I16(v) => visitor.visit_i16(v), + Content::I32(v) => visitor.visit_i32(v), + Content::I64(v) => visitor.visit_i64(v), + _ => Err(self.invalid_type(&visitor)), + } + } + + fn deserialize_float<V>(self, visitor: V) -> Result<V::Value, E> + where + V: Visitor<'de>, + { + match self.content { + Content::F32(v) => visitor.visit_f32(v), + Content::F64(v) => visitor.visit_f64(v), + Content::U8(v) => visitor.visit_u8(v), + Content::U16(v) => visitor.visit_u16(v), + Content::U32(v) => visitor.visit_u32(v), + Content::U64(v) => visitor.visit_u64(v), + Content::I8(v) => visitor.visit_i8(v), + Content::I16(v) => visitor.visit_i16(v), + Content::I32(v) => visitor.visit_i32(v), + Content::I64(v) => visitor.visit_i64(v), + _ => Err(self.invalid_type(&visitor)), + } + } + } + + fn visit_content_seq<'de, V, E>(content: Vec<Content<'de>>, visitor: V) -> Result<V::Value, E> + where + V: Visitor<'de>, + E: de::Error, + { + let seq = content.into_iter().map(ContentDeserializer::new); + let mut seq_visitor = de::value::SeqDeserializer::new(seq); + let value = try!(visitor.visit_seq(&mut seq_visitor)); + try!(seq_visitor.end()); + Ok(value) + } + + fn visit_content_map<'de, V, E>( + content: Vec<(Content<'de>, Content<'de>)>, + visitor: V, + ) -> Result<V::Value, E> + where + V: Visitor<'de>, + E: de::Error, + { + let map = content + .into_iter() + .map(|(k, v)| (ContentDeserializer::new(k), ContentDeserializer::new(v))); + let mut map_visitor = de::value::MapDeserializer::new(map); + let value = try!(visitor.visit_map(&mut map_visitor)); + try!(map_visitor.end()); + Ok(value) + } + + /// Used when deserializing an internally tagged enum because the content + /// will be used exactly once. + impl<'de, E> Deserializer<'de> for ContentDeserializer<'de, E> + where + E: de::Error, + { + type Error = E; + + fn deserialize_any<V>(self, visitor: V) -> Result<V::Value, Self::Error> + where + V: Visitor<'de>, + { + match self.content { + Content::Bool(v) => visitor.visit_bool(v), + Content::U8(v) => visitor.visit_u8(v), + Content::U16(v) => visitor.visit_u16(v), + Content::U32(v) => visitor.visit_u32(v), + Content::U64(v) => visitor.visit_u64(v), + Content::I8(v) => visitor.visit_i8(v), + Content::I16(v) => visitor.visit_i16(v), + Content::I32(v) => visitor.visit_i32(v), + Content::I64(v) => visitor.visit_i64(v), + Content::F32(v) => visitor.visit_f32(v), + Content::F64(v) => visitor.visit_f64(v), + Content::Char(v) => visitor.visit_char(v), + Content::String(v) => visitor.visit_string(v), + Content::Str(v) => visitor.visit_borrowed_str(v), + Content::ByteBuf(v) => visitor.visit_byte_buf(v), + Content::Bytes(v) => visitor.visit_borrowed_bytes(v), + Content::Unit => visitor.visit_unit(), + Content::None => visitor.visit_none(), + Content::Some(v) => visitor.visit_some(ContentDeserializer::new(*v)), + Content::Newtype(v) => visitor.visit_newtype_struct(ContentDeserializer::new(*v)), + Content::Seq(v) => visit_content_seq(v, visitor), + Content::Map(v) => visit_content_map(v, visitor), + } + } + + fn deserialize_bool<V>(self, visitor: V) -> Result<V::Value, Self::Error> + where + V: Visitor<'de>, + { + match self.content { + Content::Bool(v) => visitor.visit_bool(v), + _ => Err(self.invalid_type(&visitor)), + } + } + + fn deserialize_i8<V>(self, visitor: V) -> Result<V::Value, Self::Error> + where + V: Visitor<'de>, + { + self.deserialize_integer(visitor) + } + + fn deserialize_i16<V>(self, visitor: V) -> Result<V::Value, Self::Error> + where + V: Visitor<'de>, + { + self.deserialize_integer(visitor) + } + + fn deserialize_i32<V>(self, visitor: V) -> Result<V::Value, Self::Error> + where + V: Visitor<'de>, + { + self.deserialize_integer(visitor) + } + + fn deserialize_i64<V>(self, visitor: V) -> Result<V::Value, Self::Error> + where + V: Visitor<'de>, + { + self.deserialize_integer(visitor) + } + + fn deserialize_u8<V>(self, visitor: V) -> Result<V::Value, Self::Error> + where + V: Visitor<'de>, + { + self.deserialize_integer(visitor) + } + + fn deserialize_u16<V>(self, visitor: V) -> Result<V::Value, Self::Error> + where + V: Visitor<'de>, + { + self.deserialize_integer(visitor) + } + + fn deserialize_u32<V>(self, visitor: V) -> Result<V::Value, Self::Error> + where + V: Visitor<'de>, + { + self.deserialize_integer(visitor) + } + + fn deserialize_u64<V>(self, visitor: V) -> Result<V::Value, Self::Error> + where + V: Visitor<'de>, + { + self.deserialize_integer(visitor) + } + + fn deserialize_f32<V>(self, visitor: V) -> Result<V::Value, Self::Error> + where + V: Visitor<'de>, + { + self.deserialize_float(visitor) + } + + fn deserialize_f64<V>(self, visitor: V) -> Result<V::Value, Self::Error> + where + V: Visitor<'de>, + { + self.deserialize_float(visitor) + } + + fn deserialize_char<V>(self, visitor: V) -> Result<V::Value, Self::Error> + where + V: Visitor<'de>, + { + match self.content { + Content::Char(v) => visitor.visit_char(v), + Content::String(v) => visitor.visit_string(v), + Content::Str(v) => visitor.visit_borrowed_str(v), + _ => Err(self.invalid_type(&visitor)), + } + } + + fn deserialize_str<V>(self, visitor: V) -> Result<V::Value, Self::Error> + where + V: Visitor<'de>, + { + self.deserialize_string(visitor) + } + + fn deserialize_string<V>(self, visitor: V) -> Result<V::Value, Self::Error> + where + V: Visitor<'de>, + { + match self.content { + Content::String(v) => visitor.visit_string(v), + Content::Str(v) => visitor.visit_borrowed_str(v), + Content::ByteBuf(v) => visitor.visit_byte_buf(v), + Content::Bytes(v) => visitor.visit_borrowed_bytes(v), + _ => Err(self.invalid_type(&visitor)), + } + } + + fn deserialize_bytes<V>(self, visitor: V) -> Result<V::Value, Self::Error> + where + V: Visitor<'de>, + { + self.deserialize_byte_buf(visitor) + } + + fn deserialize_byte_buf<V>(self, visitor: V) -> Result<V::Value, Self::Error> + where + V: Visitor<'de>, + { + match self.content { + Content::String(v) => visitor.visit_string(v), + Content::Str(v) => visitor.visit_borrowed_str(v), + Content::ByteBuf(v) => visitor.visit_byte_buf(v), + Content::Bytes(v) => visitor.visit_borrowed_bytes(v), + Content::Seq(v) => visit_content_seq(v, visitor), + _ => Err(self.invalid_type(&visitor)), + } + } + + fn deserialize_option<V>(self, visitor: V) -> Result<V::Value, Self::Error> + where + V: Visitor<'de>, + { + match self.content { + Content::None => visitor.visit_none(), + Content::Some(v) => visitor.visit_some(ContentDeserializer::new(*v)), + Content::Unit => visitor.visit_unit(), + _ => visitor.visit_some(self), + } + } + + fn deserialize_unit<V>(self, visitor: V) -> Result<V::Value, Self::Error> + where + V: Visitor<'de>, + { + match self.content { + Content::Unit => visitor.visit_unit(), + + // Allow deserializing newtype variant containing unit. + // + // #[derive(Deserialize)] + // #[serde(tag = "result")] + // enum Response<T> { + // Success(T), + // } + // + // We want {"result":"Success"} to deserialize into Response<()>. + Content::Map(ref v) if v.is_empty() => visitor.visit_unit(), + _ => Err(self.invalid_type(&visitor)), + } + } + + fn deserialize_unit_struct<V>( + self, + _name: &'static str, + visitor: V, + ) -> Result<V::Value, Self::Error> + where + V: Visitor<'de>, + { + match self.content { + // As a special case, allow deserializing untagged newtype + // variant containing unit struct. + // + // #[derive(Deserialize)] + // struct Info; + // + // #[derive(Deserialize)] + // #[serde(tag = "topic")] + // enum Message { + // Info(Info), + // } + // + // We want {"topic":"Info"} to deserialize even though + // ordinarily unit structs do not deserialize from empty map/seq. + Content::Map(ref v) if v.is_empty() => visitor.visit_unit(), + Content::Seq(ref v) if v.is_empty() => visitor.visit_unit(), + _ => self.deserialize_any(visitor), + } + } + + fn deserialize_newtype_struct<V>( + self, + _name: &str, + visitor: V, + ) -> Result<V::Value, Self::Error> + where + V: Visitor<'de>, + { + match self.content { + Content::Newtype(v) => visitor.visit_newtype_struct(ContentDeserializer::new(*v)), + _ => visitor.visit_newtype_struct(self), + } + } + + fn deserialize_seq<V>(self, visitor: V) -> Result<V::Value, Self::Error> + where + V: Visitor<'de>, + { + match self.content { + Content::Seq(v) => visit_content_seq(v, visitor), + _ => Err(self.invalid_type(&visitor)), + } + } + + fn deserialize_tuple<V>(self, _len: usize, visitor: V) -> Result<V::Value, Self::Error> + where + V: Visitor<'de>, + { + self.deserialize_seq(visitor) + } + + fn deserialize_tuple_struct<V>( + self, + _name: &'static str, + _len: usize, + visitor: V, + ) -> Result<V::Value, Self::Error> + where + V: Visitor<'de>, + { + self.deserialize_seq(visitor) + } + + fn deserialize_map<V>(self, visitor: V) -> Result<V::Value, Self::Error> + where + V: Visitor<'de>, + { + match self.content { + Content::Map(v) => visit_content_map(v, visitor), + _ => Err(self.invalid_type(&visitor)), + } + } + + fn deserialize_struct<V>( + self, + _name: &'static str, + _fields: &'static [&'static str], + visitor: V, + ) -> Result<V::Value, Self::Error> + where + V: Visitor<'de>, + { + match self.content { + Content::Seq(v) => visit_content_seq(v, visitor), + Content::Map(v) => visit_content_map(v, visitor), + _ => Err(self.invalid_type(&visitor)), + } + } + + fn deserialize_enum<V>( + self, + _name: &str, + _variants: &'static [&'static str], + visitor: V, + ) -> Result<V::Value, Self::Error> + where + V: Visitor<'de>, + { + let (variant, value) = match self.content { + Content::Map(value) => { + let mut iter = value.into_iter(); + let (variant, value) = match iter.next() { + Some(v) => v, + None => { + return Err(de::Error::invalid_value( + de::Unexpected::Map, + &"map with a single key", + )); + } + }; + // enums are encoded in json as maps with a single key:value pair + if iter.next().is_some() { + return Err(de::Error::invalid_value( + de::Unexpected::Map, + &"map with a single key", + )); + } + (variant, Some(value)) + } + s @ Content::String(_) | s @ Content::Str(_) => (s, None), + other => { + return Err(de::Error::invalid_type( + other.unexpected(), + &"string or map", + )); + } + }; + + visitor.visit_enum(EnumDeserializer::new(variant, value)) + } + + fn deserialize_identifier<V>(self, visitor: V) -> Result<V::Value, Self::Error> + where + V: Visitor<'de>, + { + match self.content { + Content::String(v) => visitor.visit_string(v), + Content::Str(v) => visitor.visit_borrowed_str(v), + Content::ByteBuf(v) => visitor.visit_byte_buf(v), + Content::Bytes(v) => visitor.visit_borrowed_bytes(v), + Content::U8(v) => visitor.visit_u8(v), + Content::U64(v) => visitor.visit_u64(v), + _ => Err(self.invalid_type(&visitor)), + } + } + + fn deserialize_ignored_any<V>(self, visitor: V) -> Result<V::Value, Self::Error> + where + V: Visitor<'de>, + { + drop(self); + visitor.visit_unit() + } + + fn __deserialize_content<V>( + self, + _: actually_private::T, + visitor: V, + ) -> Result<Content<'de>, Self::Error> + where + V: Visitor<'de, Value = Content<'de>>, + { + let _ = visitor; + Ok(self.content) + } + } + + impl<'de, E> ContentDeserializer<'de, E> { + /// private API, don't use + pub fn new(content: Content<'de>) -> Self { + ContentDeserializer { + content: content, + err: PhantomData, + } + } + } + + pub struct EnumDeserializer<'de, E> + where + E: de::Error, + { + variant: Content<'de>, + value: Option<Content<'de>>, + err: PhantomData<E>, + } + + impl<'de, E> EnumDeserializer<'de, E> + where + E: de::Error, + { + pub fn new(variant: Content<'de>, value: Option<Content<'de>>) -> EnumDeserializer<'de, E> { + EnumDeserializer { + variant: variant, + value: value, + err: PhantomData, + } + } + } + + impl<'de, E> de::EnumAccess<'de> for EnumDeserializer<'de, E> + where + E: de::Error, + { + type Error = E; + type Variant = VariantDeserializer<'de, Self::Error>; + + fn variant_seed<V>(self, seed: V) -> Result<(V::Value, Self::Variant), E> + where + V: de::DeserializeSeed<'de>, + { + let visitor = VariantDeserializer { + value: self.value, + err: PhantomData, + }; + seed.deserialize(ContentDeserializer::new(self.variant)) + .map(|v| (v, visitor)) + } + } + + pub struct VariantDeserializer<'de, E> + where + E: de::Error, + { + value: Option<Content<'de>>, + err: PhantomData<E>, + } + + impl<'de, E> de::VariantAccess<'de> for VariantDeserializer<'de, E> + where + E: de::Error, + { + type Error = E; + + fn unit_variant(self) -> Result<(), E> { + match self.value { + Some(value) => de::Deserialize::deserialize(ContentDeserializer::new(value)), + None => Ok(()), + } + } + + fn newtype_variant_seed<T>(self, seed: T) -> Result<T::Value, E> + where + T: de::DeserializeSeed<'de>, + { + match self.value { + Some(value) => seed.deserialize(ContentDeserializer::new(value)), + None => Err(de::Error::invalid_type( + de::Unexpected::UnitVariant, + &"newtype variant", + )), + } + } + + fn tuple_variant<V>(self, _len: usize, visitor: V) -> Result<V::Value, Self::Error> + where + V: de::Visitor<'de>, + { + match self.value { + Some(Content::Seq(v)) => { + de::Deserializer::deserialize_any(SeqDeserializer::new(v), visitor) + } + Some(other) => Err(de::Error::invalid_type( + other.unexpected(), + &"tuple variant", + )), + None => Err(de::Error::invalid_type( + de::Unexpected::UnitVariant, + &"tuple variant", + )), + } + } + + fn struct_variant<V>( + self, + _fields: &'static [&'static str], + visitor: V, + ) -> Result<V::Value, Self::Error> + where + V: de::Visitor<'de>, + { + match self.value { + Some(Content::Map(v)) => { + de::Deserializer::deserialize_any(MapDeserializer::new(v), visitor) + } + Some(Content::Seq(v)) => { + de::Deserializer::deserialize_any(SeqDeserializer::new(v), visitor) + } + Some(other) => Err(de::Error::invalid_type( + other.unexpected(), + &"struct variant", + )), + None => Err(de::Error::invalid_type( + de::Unexpected::UnitVariant, + &"struct variant", + )), + } + } + } + + struct SeqDeserializer<'de, E> + where + E: de::Error, + { + iter: <Vec<Content<'de>> as IntoIterator>::IntoIter, + err: PhantomData<E>, + } + + impl<'de, E> SeqDeserializer<'de, E> + where + E: de::Error, + { + fn new(vec: Vec<Content<'de>>) -> Self { + SeqDeserializer { + iter: vec.into_iter(), + err: PhantomData, + } + } + } + + impl<'de, E> de::Deserializer<'de> for SeqDeserializer<'de, E> + where + E: de::Error, + { + type Error = E; + + #[inline] + fn deserialize_any<V>(mut self, visitor: V) -> Result<V::Value, Self::Error> + where + V: de::Visitor<'de>, + { + let len = self.iter.len(); + if len == 0 { + visitor.visit_unit() + } else { + let ret = try!(visitor.visit_seq(&mut self)); + let remaining = self.iter.len(); + if remaining == 0 { + Ok(ret) + } else { + Err(de::Error::invalid_length(len, &"fewer elements in array")) + } + } + } + + forward_to_deserialize_any! { + bool i8 i16 i32 i64 i128 u8 u16 u32 u64 u128 f32 f64 char str string + bytes byte_buf option unit unit_struct newtype_struct seq tuple + tuple_struct map struct enum identifier ignored_any + } + } + + impl<'de, E> de::SeqAccess<'de> for SeqDeserializer<'de, E> + where + E: de::Error, + { + type Error = E; + + fn next_element_seed<T>(&mut self, seed: T) -> Result<Option<T::Value>, Self::Error> + where + T: de::DeserializeSeed<'de>, + { + match self.iter.next() { + Some(value) => seed.deserialize(ContentDeserializer::new(value)).map(Some), + None => Ok(None), + } + } + + fn size_hint(&self) -> Option<usize> { + size_hint::from_bounds(&self.iter) + } + } + + struct MapDeserializer<'de, E> + where + E: de::Error, + { + iter: <Vec<(Content<'de>, Content<'de>)> as IntoIterator>::IntoIter, + value: Option<Content<'de>>, + err: PhantomData<E>, + } + + impl<'de, E> MapDeserializer<'de, E> + where + E: de::Error, + { + fn new(map: Vec<(Content<'de>, Content<'de>)>) -> Self { + MapDeserializer { + iter: map.into_iter(), + value: None, + err: PhantomData, + } + } + } + + impl<'de, E> de::MapAccess<'de> for MapDeserializer<'de, E> + where + E: de::Error, + { + type Error = E; + + fn next_key_seed<T>(&mut self, seed: T) -> Result<Option<T::Value>, Self::Error> + where + T: de::DeserializeSeed<'de>, + { + match self.iter.next() { + Some((key, value)) => { + self.value = Some(value); + seed.deserialize(ContentDeserializer::new(key)).map(Some) + } + None => Ok(None), + } + } + + fn next_value_seed<T>(&mut self, seed: T) -> Result<T::Value, Self::Error> + where + T: de::DeserializeSeed<'de>, + { + match self.value.take() { + Some(value) => seed.deserialize(ContentDeserializer::new(value)), + None => Err(de::Error::custom("value is missing")), + } + } + + fn size_hint(&self) -> Option<usize> { + size_hint::from_bounds(&self.iter) + } + } + + impl<'de, E> de::Deserializer<'de> for MapDeserializer<'de, E> + where + E: de::Error, + { + type Error = E; + + #[inline] + fn deserialize_any<V>(self, visitor: V) -> Result<V::Value, Self::Error> + where + V: de::Visitor<'de>, + { + visitor.visit_map(self) + } + + forward_to_deserialize_any! { + bool i8 i16 i32 i64 i128 u8 u16 u32 u64 u128 f32 f64 char str string + bytes byte_buf option unit unit_struct newtype_struct seq tuple + tuple_struct map struct enum identifier ignored_any + } + } + + /// Not public API. + pub struct ContentRefDeserializer<'a, 'de: 'a, E> { + content: &'a Content<'de>, + err: PhantomData<E>, + } + + impl<'a, 'de, E> ContentRefDeserializer<'a, 'de, E> + where + E: de::Error, + { + #[cold] + fn invalid_type(self, exp: &Expected) -> E { + de::Error::invalid_type(self.content.unexpected(), exp) + } + + fn deserialize_integer<V>(self, visitor: V) -> Result<V::Value, E> + where + V: Visitor<'de>, + { + match *self.content { + Content::U8(v) => visitor.visit_u8(v), + Content::U16(v) => visitor.visit_u16(v), + Content::U32(v) => visitor.visit_u32(v), + Content::U64(v) => visitor.visit_u64(v), + Content::I8(v) => visitor.visit_i8(v), + Content::I16(v) => visitor.visit_i16(v), + Content::I32(v) => visitor.visit_i32(v), + Content::I64(v) => visitor.visit_i64(v), + _ => Err(self.invalid_type(&visitor)), + } + } + + fn deserialize_float<V>(self, visitor: V) -> Result<V::Value, E> + where + V: Visitor<'de>, + { + match *self.content { + Content::F32(v) => visitor.visit_f32(v), + Content::F64(v) => visitor.visit_f64(v), + Content::U8(v) => visitor.visit_u8(v), + Content::U16(v) => visitor.visit_u16(v), + Content::U32(v) => visitor.visit_u32(v), + Content::U64(v) => visitor.visit_u64(v), + Content::I8(v) => visitor.visit_i8(v), + Content::I16(v) => visitor.visit_i16(v), + Content::I32(v) => visitor.visit_i32(v), + Content::I64(v) => visitor.visit_i64(v), + _ => Err(self.invalid_type(&visitor)), + } + } + } + + fn visit_content_seq_ref<'a, 'de, V, E>( + content: &'a [Content<'de>], + visitor: V, + ) -> Result<V::Value, E> + where + V: Visitor<'de>, + E: de::Error, + { + let seq = content.iter().map(ContentRefDeserializer::new); + let mut seq_visitor = de::value::SeqDeserializer::new(seq); + let value = try!(visitor.visit_seq(&mut seq_visitor)); + try!(seq_visitor.end()); + Ok(value) + } + + fn visit_content_map_ref<'a, 'de, V, E>( + content: &'a [(Content<'de>, Content<'de>)], + visitor: V, + ) -> Result<V::Value, E> + where + V: Visitor<'de>, + E: de::Error, + { + let map = content.iter().map(|(k, v)| { + ( + ContentRefDeserializer::new(k), + ContentRefDeserializer::new(v), + ) + }); + let mut map_visitor = de::value::MapDeserializer::new(map); + let value = try!(visitor.visit_map(&mut map_visitor)); + try!(map_visitor.end()); + Ok(value) + } + + /// Used when deserializing an untagged enum because the content may need + /// to be used more than once. + impl<'de, 'a, E> Deserializer<'de> for ContentRefDeserializer<'a, 'de, E> + where + E: de::Error, + { + type Error = E; + + fn deserialize_any<V>(self, visitor: V) -> Result<V::Value, E> + where + V: Visitor<'de>, + { + match *self.content { + Content::Bool(v) => visitor.visit_bool(v), + Content::U8(v) => visitor.visit_u8(v), + Content::U16(v) => visitor.visit_u16(v), + Content::U32(v) => visitor.visit_u32(v), + Content::U64(v) => visitor.visit_u64(v), + Content::I8(v) => visitor.visit_i8(v), + Content::I16(v) => visitor.visit_i16(v), + Content::I32(v) => visitor.visit_i32(v), + Content::I64(v) => visitor.visit_i64(v), + Content::F32(v) => visitor.visit_f32(v), + Content::F64(v) => visitor.visit_f64(v), + Content::Char(v) => visitor.visit_char(v), + Content::String(ref v) => visitor.visit_str(v), + Content::Str(v) => visitor.visit_borrowed_str(v), + Content::ByteBuf(ref v) => visitor.visit_bytes(v), + Content::Bytes(v) => visitor.visit_borrowed_bytes(v), + Content::Unit => visitor.visit_unit(), + Content::None => visitor.visit_none(), + Content::Some(ref v) => visitor.visit_some(ContentRefDeserializer::new(v)), + Content::Newtype(ref v) => { + visitor.visit_newtype_struct(ContentRefDeserializer::new(v)) + } + Content::Seq(ref v) => visit_content_seq_ref(v, visitor), + Content::Map(ref v) => visit_content_map_ref(v, visitor), + } + } + + fn deserialize_bool<V>(self, visitor: V) -> Result<V::Value, Self::Error> + where + V: Visitor<'de>, + { + match *self.content { + Content::Bool(v) => visitor.visit_bool(v), + _ => Err(self.invalid_type(&visitor)), + } + } + + fn deserialize_i8<V>(self, visitor: V) -> Result<V::Value, Self::Error> + where + V: Visitor<'de>, + { + self.deserialize_integer(visitor) + } + + fn deserialize_i16<V>(self, visitor: V) -> Result<V::Value, Self::Error> + where + V: Visitor<'de>, + { + self.deserialize_integer(visitor) + } + + fn deserialize_i32<V>(self, visitor: V) -> Result<V::Value, Self::Error> + where + V: Visitor<'de>, + { + self.deserialize_integer(visitor) + } + + fn deserialize_i64<V>(self, visitor: V) -> Result<V::Value, Self::Error> + where + V: Visitor<'de>, + { + self.deserialize_integer(visitor) + } + + fn deserialize_u8<V>(self, visitor: V) -> Result<V::Value, Self::Error> + where + V: Visitor<'de>, + { + self.deserialize_integer(visitor) + } + + fn deserialize_u16<V>(self, visitor: V) -> Result<V::Value, Self::Error> + where + V: Visitor<'de>, + { + self.deserialize_integer(visitor) + } + + fn deserialize_u32<V>(self, visitor: V) -> Result<V::Value, Self::Error> + where + V: Visitor<'de>, + { + self.deserialize_integer(visitor) + } + + fn deserialize_u64<V>(self, visitor: V) -> Result<V::Value, Self::Error> + where + V: Visitor<'de>, + { + self.deserialize_integer(visitor) + } + + fn deserialize_f32<V>(self, visitor: V) -> Result<V::Value, Self::Error> + where + V: Visitor<'de>, + { + self.deserialize_float(visitor) + } + + fn deserialize_f64<V>(self, visitor: V) -> Result<V::Value, Self::Error> + where + V: Visitor<'de>, + { + self.deserialize_float(visitor) + } + + fn deserialize_char<V>(self, visitor: V) -> Result<V::Value, Self::Error> + where + V: Visitor<'de>, + { + match *self.content { + Content::Char(v) => visitor.visit_char(v), + Content::String(ref v) => visitor.visit_str(v), + Content::Str(v) => visitor.visit_borrowed_str(v), + _ => Err(self.invalid_type(&visitor)), + } + } + + fn deserialize_str<V>(self, visitor: V) -> Result<V::Value, Self::Error> + where + V: Visitor<'de>, + { + match *self.content { + Content::String(ref v) => visitor.visit_str(v), + Content::Str(v) => visitor.visit_borrowed_str(v), + Content::ByteBuf(ref v) => visitor.visit_bytes(v), + Content::Bytes(v) => visitor.visit_borrowed_bytes(v), + _ => Err(self.invalid_type(&visitor)), + } + } + + fn deserialize_string<V>(self, visitor: V) -> Result<V::Value, Self::Error> + where + V: Visitor<'de>, + { + self.deserialize_str(visitor) + } + + fn deserialize_bytes<V>(self, visitor: V) -> Result<V::Value, Self::Error> + where + V: Visitor<'de>, + { + match *self.content { + Content::String(ref v) => visitor.visit_str(v), + Content::Str(v) => visitor.visit_borrowed_str(v), + Content::ByteBuf(ref v) => visitor.visit_bytes(v), + Content::Bytes(v) => visitor.visit_borrowed_bytes(v), + Content::Seq(ref v) => visit_content_seq_ref(v, visitor), + _ => Err(self.invalid_type(&visitor)), + } + } + + fn deserialize_byte_buf<V>(self, visitor: V) -> Result<V::Value, Self::Error> + where + V: Visitor<'de>, + { + self.deserialize_bytes(visitor) + } + + fn deserialize_option<V>(self, visitor: V) -> Result<V::Value, E> + where + V: Visitor<'de>, + { + match *self.content { + Content::None => visitor.visit_none(), + Content::Some(ref v) => visitor.visit_some(ContentRefDeserializer::new(v)), + Content::Unit => visitor.visit_unit(), + _ => visitor.visit_some(self), + } + } + + fn deserialize_unit<V>(self, visitor: V) -> Result<V::Value, Self::Error> + where + V: Visitor<'de>, + { + match *self.content { + Content::Unit => visitor.visit_unit(), + _ => Err(self.invalid_type(&visitor)), + } + } + + fn deserialize_unit_struct<V>( + self, + _name: &'static str, + visitor: V, + ) -> Result<V::Value, Self::Error> + where + V: Visitor<'de>, + { + self.deserialize_unit(visitor) + } + + fn deserialize_newtype_struct<V>(self, _name: &str, visitor: V) -> Result<V::Value, E> + where + V: Visitor<'de>, + { + match *self.content { + Content::Newtype(ref v) => { + visitor.visit_newtype_struct(ContentRefDeserializer::new(v)) + } + _ => visitor.visit_newtype_struct(self), + } + } + + fn deserialize_seq<V>(self, visitor: V) -> Result<V::Value, Self::Error> + where + V: Visitor<'de>, + { + match *self.content { + Content::Seq(ref v) => visit_content_seq_ref(v, visitor), + _ => Err(self.invalid_type(&visitor)), + } + } + + fn deserialize_tuple<V>(self, _len: usize, visitor: V) -> Result<V::Value, Self::Error> + where + V: Visitor<'de>, + { + self.deserialize_seq(visitor) + } + + fn deserialize_tuple_struct<V>( + self, + _name: &'static str, + _len: usize, + visitor: V, + ) -> Result<V::Value, Self::Error> + where + V: Visitor<'de>, + { + self.deserialize_seq(visitor) + } + + fn deserialize_map<V>(self, visitor: V) -> Result<V::Value, Self::Error> + where + V: Visitor<'de>, + { + match *self.content { + Content::Map(ref v) => visit_content_map_ref(v, visitor), + _ => Err(self.invalid_type(&visitor)), + } + } + + fn deserialize_struct<V>( + self, + _name: &'static str, + _fields: &'static [&'static str], + visitor: V, + ) -> Result<V::Value, Self::Error> + where + V: Visitor<'de>, + { + match *self.content { + Content::Seq(ref v) => visit_content_seq_ref(v, visitor), + Content::Map(ref v) => visit_content_map_ref(v, visitor), + _ => Err(self.invalid_type(&visitor)), + } + } + + fn deserialize_enum<V>( + self, + _name: &str, + _variants: &'static [&'static str], + visitor: V, + ) -> Result<V::Value, Self::Error> + where + V: Visitor<'de>, + { + let (variant, value) = match *self.content { + Content::Map(ref value) => { + let mut iter = value.iter(); + let (variant, value) = match iter.next() { + Some(v) => v, + None => { + return Err(de::Error::invalid_value( + de::Unexpected::Map, + &"map with a single key", + )); + } + }; + // enums are encoded in json as maps with a single key:value pair + if iter.next().is_some() { + return Err(de::Error::invalid_value( + de::Unexpected::Map, + &"map with a single key", + )); + } + (variant, Some(value)) + } + ref s @ Content::String(_) | ref s @ Content::Str(_) => (s, None), + ref other => { + return Err(de::Error::invalid_type( + other.unexpected(), + &"string or map", + )); + } + }; + + visitor.visit_enum(EnumRefDeserializer { + variant: variant, + value: value, + err: PhantomData, + }) + } + + fn deserialize_identifier<V>(self, visitor: V) -> Result<V::Value, Self::Error> + where + V: Visitor<'de>, + { + match *self.content { + Content::String(ref v) => visitor.visit_str(v), + Content::Str(v) => visitor.visit_borrowed_str(v), + Content::ByteBuf(ref v) => visitor.visit_bytes(v), + Content::Bytes(v) => visitor.visit_borrowed_bytes(v), + Content::U8(v) => visitor.visit_u8(v), + Content::U64(v) => visitor.visit_u64(v), + _ => Err(self.invalid_type(&visitor)), + } + } + + fn deserialize_ignored_any<V>(self, visitor: V) -> Result<V::Value, Self::Error> + where + V: Visitor<'de>, + { + visitor.visit_unit() + } + + fn __deserialize_content<V>( + self, + _: actually_private::T, + visitor: V, + ) -> Result<Content<'de>, Self::Error> + where + V: Visitor<'de, Value = Content<'de>>, + { + let _ = visitor; + Ok(self.content.clone()) + } + } + + impl<'a, 'de, E> ContentRefDeserializer<'a, 'de, E> { + /// private API, don't use + pub fn new(content: &'a Content<'de>) -> Self { + ContentRefDeserializer { + content: content, + err: PhantomData, + } + } + } + + struct EnumRefDeserializer<'a, 'de: 'a, E> + where + E: de::Error, + { + variant: &'a Content<'de>, + value: Option<&'a Content<'de>>, + err: PhantomData<E>, + } + + impl<'de, 'a, E> de::EnumAccess<'de> for EnumRefDeserializer<'a, 'de, E> + where + E: de::Error, + { + type Error = E; + type Variant = VariantRefDeserializer<'a, 'de, Self::Error>; + + fn variant_seed<V>(self, seed: V) -> Result<(V::Value, Self::Variant), Self::Error> + where + V: de::DeserializeSeed<'de>, + { + let visitor = VariantRefDeserializer { + value: self.value, + err: PhantomData, + }; + seed.deserialize(ContentRefDeserializer::new(self.variant)) + .map(|v| (v, visitor)) + } + } + + struct VariantRefDeserializer<'a, 'de: 'a, E> + where + E: de::Error, + { + value: Option<&'a Content<'de>>, + err: PhantomData<E>, + } + + impl<'de, 'a, E> de::VariantAccess<'de> for VariantRefDeserializer<'a, 'de, E> + where + E: de::Error, + { + type Error = E; + + fn unit_variant(self) -> Result<(), E> { + match self.value { + Some(value) => de::Deserialize::deserialize(ContentRefDeserializer::new(value)), + None => Ok(()), + } + } + + fn newtype_variant_seed<T>(self, seed: T) -> Result<T::Value, E> + where + T: de::DeserializeSeed<'de>, + { + match self.value { + Some(value) => seed.deserialize(ContentRefDeserializer::new(value)), + None => Err(de::Error::invalid_type( + de::Unexpected::UnitVariant, + &"newtype variant", + )), + } + } + + fn tuple_variant<V>(self, _len: usize, visitor: V) -> Result<V::Value, Self::Error> + where + V: de::Visitor<'de>, + { + match self.value { + Some(Content::Seq(v)) => { + de::Deserializer::deserialize_any(SeqRefDeserializer::new(v), visitor) + } + Some(other) => Err(de::Error::invalid_type( + other.unexpected(), + &"tuple variant", + )), + None => Err(de::Error::invalid_type( + de::Unexpected::UnitVariant, + &"tuple variant", + )), + } + } + + fn struct_variant<V>( + self, + _fields: &'static [&'static str], + visitor: V, + ) -> Result<V::Value, Self::Error> + where + V: de::Visitor<'de>, + { + match self.value { + Some(Content::Map(v)) => { + de::Deserializer::deserialize_any(MapRefDeserializer::new(v), visitor) + } + Some(Content::Seq(v)) => { + de::Deserializer::deserialize_any(SeqRefDeserializer::new(v), visitor) + } + Some(other) => Err(de::Error::invalid_type( + other.unexpected(), + &"struct variant", + )), + None => Err(de::Error::invalid_type( + de::Unexpected::UnitVariant, + &"struct variant", + )), + } + } + } + + struct SeqRefDeserializer<'a, 'de: 'a, E> + where + E: de::Error, + { + iter: <&'a [Content<'de>] as IntoIterator>::IntoIter, + err: PhantomData<E>, + } + + impl<'a, 'de, E> SeqRefDeserializer<'a, 'de, E> + where + E: de::Error, + { + fn new(slice: &'a [Content<'de>]) -> Self { + SeqRefDeserializer { + iter: slice.iter(), + err: PhantomData, + } + } + } + + impl<'de, 'a, E> de::Deserializer<'de> for SeqRefDeserializer<'a, 'de, E> + where + E: de::Error, + { + type Error = E; + + #[inline] + fn deserialize_any<V>(mut self, visitor: V) -> Result<V::Value, Self::Error> + where + V: de::Visitor<'de>, + { + let len = self.iter.len(); + if len == 0 { + visitor.visit_unit() + } else { + let ret = try!(visitor.visit_seq(&mut self)); + let remaining = self.iter.len(); + if remaining == 0 { + Ok(ret) + } else { + Err(de::Error::invalid_length(len, &"fewer elements in array")) + } + } + } + + forward_to_deserialize_any! { + bool i8 i16 i32 i64 i128 u8 u16 u32 u64 u128 f32 f64 char str string + bytes byte_buf option unit unit_struct newtype_struct seq tuple + tuple_struct map struct enum identifier ignored_any + } + } + + impl<'de, 'a, E> de::SeqAccess<'de> for SeqRefDeserializer<'a, 'de, E> + where + E: de::Error, + { + type Error = E; + + fn next_element_seed<T>(&mut self, seed: T) -> Result<Option<T::Value>, Self::Error> + where + T: de::DeserializeSeed<'de>, + { + match self.iter.next() { + Some(value) => seed + .deserialize(ContentRefDeserializer::new(value)) + .map(Some), + None => Ok(None), + } + } + + fn size_hint(&self) -> Option<usize> { + size_hint::from_bounds(&self.iter) + } + } + + struct MapRefDeserializer<'a, 'de: 'a, E> + where + E: de::Error, + { + iter: <&'a [(Content<'de>, Content<'de>)] as IntoIterator>::IntoIter, + value: Option<&'a Content<'de>>, + err: PhantomData<E>, + } + + impl<'a, 'de, E> MapRefDeserializer<'a, 'de, E> + where + E: de::Error, + { + fn new(map: &'a [(Content<'de>, Content<'de>)]) -> Self { + MapRefDeserializer { + iter: map.iter(), + value: None, + err: PhantomData, + } + } + } + + impl<'de, 'a, E> de::MapAccess<'de> for MapRefDeserializer<'a, 'de, E> + where + E: de::Error, + { + type Error = E; + + fn next_key_seed<T>(&mut self, seed: T) -> Result<Option<T::Value>, Self::Error> + where + T: de::DeserializeSeed<'de>, + { + match self.iter.next() { + Some((key, value)) => { + self.value = Some(value); + seed.deserialize(ContentRefDeserializer::new(key)).map(Some) + } + None => Ok(None), + } + } + + fn next_value_seed<T>(&mut self, seed: T) -> Result<T::Value, Self::Error> + where + T: de::DeserializeSeed<'de>, + { + match self.value.take() { + Some(value) => seed.deserialize(ContentRefDeserializer::new(value)), + None => Err(de::Error::custom("value is missing")), + } + } + + fn size_hint(&self) -> Option<usize> { + size_hint::from_bounds(&self.iter) + } + } + + impl<'de, 'a, E> de::Deserializer<'de> for MapRefDeserializer<'a, 'de, E> + where + E: de::Error, + { + type Error = E; + + #[inline] + fn deserialize_any<V>(self, visitor: V) -> Result<V::Value, Self::Error> + where + V: de::Visitor<'de>, + { + visitor.visit_map(self) + } + + forward_to_deserialize_any! { + bool i8 i16 i32 i64 i128 u8 u16 u32 u64 u128 f32 f64 char str string + bytes byte_buf option unit unit_struct newtype_struct seq tuple + tuple_struct map struct enum identifier ignored_any + } + } + + impl<'de, E> de::IntoDeserializer<'de, E> for ContentDeserializer<'de, E> + where + E: de::Error, + { + type Deserializer = Self; + + fn into_deserializer(self) -> Self { + self + } + } + + impl<'de, 'a, E> de::IntoDeserializer<'de, E> for ContentRefDeserializer<'a, 'de, E> + where + E: de::Error, + { + type Deserializer = Self; + + fn into_deserializer(self) -> Self { + self + } + } + + /// Visitor for deserializing an internally tagged unit variant. + /// + /// Not public API. + pub struct InternallyTaggedUnitVisitor<'a> { + type_name: &'a str, + variant_name: &'a str, + } + + impl<'a> InternallyTaggedUnitVisitor<'a> { + /// Not public API. + pub fn new(type_name: &'a str, variant_name: &'a str) -> Self { + InternallyTaggedUnitVisitor { + type_name: type_name, + variant_name: variant_name, + } + } + } + + impl<'de, 'a> Visitor<'de> for InternallyTaggedUnitVisitor<'a> { + type Value = (); + + fn expecting(&self, formatter: &mut fmt::Formatter) -> fmt::Result { + write!( + formatter, + "unit variant {}::{}", + self.type_name, self.variant_name + ) + } + + fn visit_seq<S>(self, _: S) -> Result<(), S::Error> + where + S: SeqAccess<'de>, + { + Ok(()) + } + + fn visit_map<M>(self, mut access: M) -> Result<(), M::Error> + where + M: MapAccess<'de>, + { + while try!(access.next_entry::<IgnoredAny, IgnoredAny>()).is_some() {} + Ok(()) + } + } + + /// Visitor for deserializing an untagged unit variant. + /// + /// Not public API. + pub struct UntaggedUnitVisitor<'a> { + type_name: &'a str, + variant_name: &'a str, + } + + impl<'a> UntaggedUnitVisitor<'a> { + /// Not public API. + pub fn new(type_name: &'a str, variant_name: &'a str) -> Self { + UntaggedUnitVisitor { + type_name: type_name, + variant_name: variant_name, + } + } + } + + impl<'de, 'a> Visitor<'de> for UntaggedUnitVisitor<'a> { + type Value = (); + + fn expecting(&self, formatter: &mut fmt::Formatter) -> fmt::Result { + write!( + formatter, + "unit variant {}::{}", + self.type_name, self.variant_name + ) + } + + fn visit_unit<E>(self) -> Result<(), E> + where + E: de::Error, + { + Ok(()) + } + + fn visit_none<E>(self) -> Result<(), E> + where + E: de::Error, + { + Ok(()) + } + } +} + +//////////////////////////////////////////////////////////////////////////////// + +// Like `IntoDeserializer` but also implemented for `&[u8]`. This is used for +// the newtype fallthrough case of `field_identifier`. +// +// #[derive(Deserialize)] +// #[serde(field_identifier)] +// enum F { +// A, +// B, +// Other(String), // deserialized using IdentifierDeserializer +// } +pub trait IdentifierDeserializer<'de, E: Error> { + type Deserializer: Deserializer<'de, Error = E>; + + fn from(self) -> Self::Deserializer; +} + +pub struct Borrowed<'de, T: 'de + ?Sized>(pub &'de T); + +impl<'de, E> IdentifierDeserializer<'de, E> for u64 +where + E: Error, +{ + type Deserializer = <u64 as IntoDeserializer<'de, E>>::Deserializer; + + fn from(self) -> Self::Deserializer { + self.into_deserializer() + } +} + +pub struct StrDeserializer<'a, E> { + value: &'a str, + marker: PhantomData<E>, +} + +impl<'de, 'a, E> Deserializer<'de> for StrDeserializer<'a, E> +where + E: Error, +{ + type Error = E; + + fn deserialize_any<V>(self, visitor: V) -> Result<V::Value, Self::Error> + where + V: Visitor<'de>, + { + visitor.visit_str(self.value) + } + + forward_to_deserialize_any! { + bool i8 i16 i32 i64 i128 u8 u16 u32 u64 u128 f32 f64 char str string + bytes byte_buf option unit unit_struct newtype_struct seq tuple + tuple_struct map struct enum identifier ignored_any + } +} + +pub struct BorrowedStrDeserializer<'de, E> { + value: &'de str, + marker: PhantomData<E>, +} + +impl<'de, E> Deserializer<'de> for BorrowedStrDeserializer<'de, E> +where + E: Error, +{ + type Error = E; + + fn deserialize_any<V>(self, visitor: V) -> Result<V::Value, Self::Error> + where + V: Visitor<'de>, + { + visitor.visit_borrowed_str(self.value) + } + + forward_to_deserialize_any! { + bool i8 i16 i32 i64 i128 u8 u16 u32 u64 u128 f32 f64 char str string + bytes byte_buf option unit unit_struct newtype_struct seq tuple + tuple_struct map struct enum identifier ignored_any + } +} + +impl<'a, E> IdentifierDeserializer<'a, E> for &'a str +where + E: Error, +{ + type Deserializer = StrDeserializer<'a, E>; + + fn from(self) -> Self::Deserializer { + StrDeserializer { + value: self, + marker: PhantomData, + } + } +} + +impl<'de, E> IdentifierDeserializer<'de, E> for Borrowed<'de, str> +where + E: Error, +{ + type Deserializer = BorrowedStrDeserializer<'de, E>; + + fn from(self) -> Self::Deserializer { + BorrowedStrDeserializer { + value: self.0, + marker: PhantomData, + } + } +} + +impl<'a, E> IdentifierDeserializer<'a, E> for &'a [u8] +where + E: Error, +{ + type Deserializer = BytesDeserializer<'a, E>; + + fn from(self) -> Self::Deserializer { + BytesDeserializer::new(self) + } +} + +impl<'de, E> IdentifierDeserializer<'de, E> for Borrowed<'de, [u8]> +where + E: Error, +{ + type Deserializer = BorrowedBytesDeserializer<'de, E>; + + fn from(self) -> Self::Deserializer { + BorrowedBytesDeserializer::new(self.0) + } +} + +#[cfg(any(feature = "std", feature = "alloc"))] +pub struct FlatMapDeserializer<'a, 'de: 'a, E>( + pub &'a mut Vec<Option<(Content<'de>, Content<'de>)>>, + pub PhantomData<E>, +); + +#[cfg(any(feature = "std", feature = "alloc"))] +impl<'a, 'de, E> FlatMapDeserializer<'a, 'de, E> +where + E: Error, +{ + fn deserialize_other<V>() -> Result<V, E> { + Err(Error::custom("can only flatten structs and maps")) + } +} + +#[cfg(any(feature = "std", feature = "alloc"))] +macro_rules! forward_to_deserialize_other { + ($($func:ident ($($arg:ty),*))*) => { + $( + fn $func<V>(self, $(_: $arg,)* _visitor: V) -> Result<V::Value, Self::Error> + where + V: Visitor<'de>, + { + Self::deserialize_other() + } + )* + } +} + +#[cfg(any(feature = "std", feature = "alloc"))] +impl<'a, 'de, E> Deserializer<'de> for FlatMapDeserializer<'a, 'de, E> +where + E: Error, +{ + type Error = E; + + fn deserialize_any<V>(self, visitor: V) -> Result<V::Value, Self::Error> + where + V: Visitor<'de>, + { + visitor.visit_map(FlatInternallyTaggedAccess { + iter: self.0.iter_mut(), + pending: None, + _marker: PhantomData, + }) + } + + fn deserialize_enum<V>( + self, + name: &'static str, + variants: &'static [&'static str], + visitor: V, + ) -> Result<V::Value, Self::Error> + where + V: Visitor<'de>, + { + for item in self.0.iter_mut() { + // items in the vector are nulled out when used. So we can only use + // an item if it's still filled in and if the field is one we care + // about. + let use_item = match *item { + None => false, + Some((ref c, _)) => c.as_str().map_or(false, |x| variants.contains(&x)), + }; + + if use_item { + let (key, value) = item.take().unwrap(); + return visitor.visit_enum(EnumDeserializer::new(key, Some(value))); + } + } + + Err(Error::custom(format_args!( + "no variant of enum {} found in flattened data", + name + ))) + } + + fn deserialize_map<V>(self, visitor: V) -> Result<V::Value, Self::Error> + where + V: Visitor<'de>, + { + visitor.visit_map(FlatMapAccess::new(self.0.iter())) + } + + fn deserialize_struct<V>( + self, + _: &'static str, + fields: &'static [&'static str], + visitor: V, + ) -> Result<V::Value, Self::Error> + where + V: Visitor<'de>, + { + visitor.visit_map(FlatStructAccess::new(self.0.iter_mut(), fields)) + } + + fn deserialize_newtype_struct<V>(self, _name: &str, visitor: V) -> Result<V::Value, Self::Error> + where + V: Visitor<'de>, + { + visitor.visit_newtype_struct(self) + } + + fn deserialize_option<V>(self, visitor: V) -> Result<V::Value, Self::Error> + where + V: Visitor<'de>, + { + match visitor.__private_visit_untagged_option(self) { + Ok(value) => Ok(value), + Err(()) => Self::deserialize_other(), + } + } + + fn deserialize_unit<V>(self, visitor: V) -> Result<V::Value, Self::Error> + where + V: Visitor<'de>, + { + visitor.visit_unit() + } + + forward_to_deserialize_other! { + deserialize_bool() + deserialize_i8() + deserialize_i16() + deserialize_i32() + deserialize_i64() + deserialize_u8() + deserialize_u16() + deserialize_u32() + deserialize_u64() + deserialize_f32() + deserialize_f64() + deserialize_char() + deserialize_str() + deserialize_string() + deserialize_bytes() + deserialize_byte_buf() + deserialize_unit_struct(&'static str) + deserialize_seq() + deserialize_tuple(usize) + deserialize_tuple_struct(&'static str, usize) + deserialize_identifier() + deserialize_ignored_any() + } +} + +#[cfg(any(feature = "std", feature = "alloc"))] +pub struct FlatMapAccess<'a, 'de: 'a, E> { + iter: slice::Iter<'a, Option<(Content<'de>, Content<'de>)>>, + pending_content: Option<&'a Content<'de>>, + _marker: PhantomData<E>, +} + +#[cfg(any(feature = "std", feature = "alloc"))] +impl<'a, 'de, E> FlatMapAccess<'a, 'de, E> { + fn new( + iter: slice::Iter<'a, Option<(Content<'de>, Content<'de>)>>, + ) -> FlatMapAccess<'a, 'de, E> { + FlatMapAccess { + iter: iter, + pending_content: None, + _marker: PhantomData, + } + } +} + +#[cfg(any(feature = "std", feature = "alloc"))] +impl<'a, 'de, E> MapAccess<'de> for FlatMapAccess<'a, 'de, E> +where + E: Error, +{ + type Error = E; + + fn next_key_seed<T>(&mut self, seed: T) -> Result<Option<T::Value>, Self::Error> + where + T: DeserializeSeed<'de>, + { + for item in &mut self.iter { + // Items in the vector are nulled out when used by a struct. + if let Some((ref key, ref content)) = *item { + self.pending_content = Some(content); + return seed.deserialize(ContentRefDeserializer::new(key)).map(Some); + } + } + Ok(None) + } + + fn next_value_seed<T>(&mut self, seed: T) -> Result<T::Value, Self::Error> + where + T: DeserializeSeed<'de>, + { + match self.pending_content.take() { + Some(value) => seed.deserialize(ContentRefDeserializer::new(value)), + None => Err(Error::custom("value is missing")), + } + } +} + +#[cfg(any(feature = "std", feature = "alloc"))] +pub struct FlatStructAccess<'a, 'de: 'a, E> { + iter: slice::IterMut<'a, Option<(Content<'de>, Content<'de>)>>, + pending_content: Option<Content<'de>>, + fields: &'static [&'static str], + _marker: PhantomData<E>, +} + +#[cfg(any(feature = "std", feature = "alloc"))] +impl<'a, 'de, E> FlatStructAccess<'a, 'de, E> { + fn new( + iter: slice::IterMut<'a, Option<(Content<'de>, Content<'de>)>>, + fields: &'static [&'static str], + ) -> FlatStructAccess<'a, 'de, E> { + FlatStructAccess { + iter: iter, + pending_content: None, + fields: fields, + _marker: PhantomData, + } + } +} + +#[cfg(any(feature = "std", feature = "alloc"))] +impl<'a, 'de, E> MapAccess<'de> for FlatStructAccess<'a, 'de, E> +where + E: Error, +{ + type Error = E; + + fn next_key_seed<T>(&mut self, seed: T) -> Result<Option<T::Value>, Self::Error> + where + T: DeserializeSeed<'de>, + { + while let Some(item) = self.iter.next() { + // items in the vector are nulled out when used. So we can only use + // an item if it's still filled in and if the field is one we care + // about. In case we do not know which fields we want, we take them all. + let use_item = match *item { + None => false, + Some((ref c, _)) => c.as_str().map_or(false, |key| self.fields.contains(&key)), + }; + + if use_item { + let (key, content) = item.take().unwrap(); + self.pending_content = Some(content); + return seed.deserialize(ContentDeserializer::new(key)).map(Some); + } + } + Ok(None) + } + + fn next_value_seed<T>(&mut self, seed: T) -> Result<T::Value, Self::Error> + where + T: DeserializeSeed<'de>, + { + match self.pending_content.take() { + Some(value) => seed.deserialize(ContentDeserializer::new(value)), + None => Err(Error::custom("value is missing")), + } + } +} + +#[cfg(any(feature = "std", feature = "alloc"))] +pub struct FlatInternallyTaggedAccess<'a, 'de: 'a, E> { + iter: slice::IterMut<'a, Option<(Content<'de>, Content<'de>)>>, + pending: Option<&'a Content<'de>>, + _marker: PhantomData<E>, +} + +#[cfg(any(feature = "std", feature = "alloc"))] +impl<'a, 'de, E> MapAccess<'de> for FlatInternallyTaggedAccess<'a, 'de, E> +where + E: Error, +{ + type Error = E; + + fn next_key_seed<T>(&mut self, seed: T) -> Result<Option<T::Value>, Self::Error> + where + T: DeserializeSeed<'de>, + { + for item in &mut self.iter { + if let Some((ref key, ref content)) = *item { + // Do not take(), instead borrow this entry. The internally tagged + // enum does its own buffering so we can't tell whether this entry + // is going to be consumed. Borrowing here leaves the entry + // available for later flattened fields. + self.pending = Some(content); + return seed.deserialize(ContentRefDeserializer::new(key)).map(Some); + } + } + Ok(None) + } + + fn next_value_seed<T>(&mut self, seed: T) -> Result<T::Value, Self::Error> + where + T: DeserializeSeed<'de>, + { + match self.pending.take() { + Some(value) => seed.deserialize(ContentRefDeserializer::new(value)), + None => panic!("value is missing"), + } + } +} diff --git a/src/private/doc.rs b/src/private/doc.rs new file mode 100644 index 0000000..f597af8 --- /dev/null +++ b/src/private/doc.rs @@ -0,0 +1,159 @@ +// Used only by Serde doc tests. Not public API. + +use lib::*; + +use ser; + +#[doc(hidden)] +#[derive(Debug)] +pub struct Error; + +impl ser::Error for Error { + fn custom<T>(_: T) -> Self + where + T: Display, + { + unimplemented!() + } +} + +#[cfg(feature = "std")] +impl error::Error for Error { + fn description(&self) -> &str { + unimplemented!() + } +} + +impl Display for Error { + fn fmt(&self, _: &mut fmt::Formatter) -> fmt::Result { + unimplemented!() + } +} + +#[doc(hidden)] +#[macro_export] +macro_rules! __private_serialize { + () => { + trait Serialize { + fn serialize<S>(&self, serializer: S) -> Result<S::Ok, S::Error> + where + S: $crate::Serializer; + } + }; +} + +#[doc(hidden)] +#[macro_export(local_inner_macros)] +macro_rules! __serialize_unimplemented { + ($($func:ident)*) => { + $( + __serialize_unimplemented_helper!($func); + )* + }; +} + +#[doc(hidden)] +#[macro_export] +macro_rules! __serialize_unimplemented_method { + ($func:ident $(<$t:ident>)* ($($arg:ty),*) -> $ret:ident) => { + fn $func $(<$t: ?Sized + $crate::Serialize>)* (self $(, _: $arg)*) -> $crate::__private::Result<Self::$ret, Self::Error> { + unimplemented!() + } + }; +} + +#[doc(hidden)] +#[macro_export(local_inner_macros)] +macro_rules! __serialize_unimplemented_helper { + (bool) => { + __serialize_unimplemented_method!(serialize_bool(bool) -> Ok); + }; + (i8) => { + __serialize_unimplemented_method!(serialize_i8(i8) -> Ok); + }; + (i16) => { + __serialize_unimplemented_method!(serialize_i16(i16) -> Ok); + }; + (i32) => { + __serialize_unimplemented_method!(serialize_i32(i32) -> Ok); + }; + (i64) => { + __serialize_unimplemented_method!(serialize_i64(i64) -> Ok); + }; + (u8) => { + __serialize_unimplemented_method!(serialize_u8(u8) -> Ok); + }; + (u16) => { + __serialize_unimplemented_method!(serialize_u16(u16) -> Ok); + }; + (u32) => { + __serialize_unimplemented_method!(serialize_u32(u32) -> Ok); + }; + (u64) => { + __serialize_unimplemented_method!(serialize_u64(u64) -> Ok); + }; + (f32) => { + __serialize_unimplemented_method!(serialize_f32(f32) -> Ok); + }; + (f64) => { + __serialize_unimplemented_method!(serialize_f64(f64) -> Ok); + }; + (char) => { + __serialize_unimplemented_method!(serialize_char(char) -> Ok); + }; + (str) => { + __serialize_unimplemented_method!(serialize_str(&str) -> Ok); + }; + (bytes) => { + __serialize_unimplemented_method!(serialize_bytes(&[u8]) -> Ok); + }; + (none) => { + __serialize_unimplemented_method!(serialize_none() -> Ok); + }; + (some) => { + __serialize_unimplemented_method!(serialize_some<T>(&T) -> Ok); + }; + (unit) => { + __serialize_unimplemented_method!(serialize_unit() -> Ok); + }; + (unit_struct) => { + __serialize_unimplemented_method!(serialize_unit_struct(&str) -> Ok); + }; + (unit_variant) => { + __serialize_unimplemented_method!(serialize_unit_variant(&str, u32, &str) -> Ok); + }; + (newtype_struct) => { + __serialize_unimplemented_method!(serialize_newtype_struct<T>(&str, &T) -> Ok); + }; + (newtype_variant) => { + __serialize_unimplemented_method!(serialize_newtype_variant<T>(&str, u32, &str, &T) -> Ok); + }; + (seq) => { + type SerializeSeq = $crate::ser::Impossible<Self::Ok, Self::Error>; + __serialize_unimplemented_method!(serialize_seq(Option<usize>) -> SerializeSeq); + }; + (tuple) => { + type SerializeTuple = $crate::ser::Impossible<Self::Ok, Self::Error>; + __serialize_unimplemented_method!(serialize_tuple(usize) -> SerializeTuple); + }; + (tuple_struct) => { + type SerializeTupleStruct = $crate::ser::Impossible<Self::Ok, Self::Error>; + __serialize_unimplemented_method!(serialize_tuple_struct(&str, usize) -> SerializeTupleStruct); + }; + (tuple_variant) => { + type SerializeTupleVariant = $crate::ser::Impossible<Self::Ok, Self::Error>; + __serialize_unimplemented_method!(serialize_tuple_variant(&str, u32, &str, usize) -> SerializeTupleVariant); + }; + (map) => { + type SerializeMap = $crate::ser::Impossible<Self::Ok, Self::Error>; + __serialize_unimplemented_method!(serialize_map(Option<usize>) -> SerializeMap); + }; + (struct) => { + type SerializeStruct = $crate::ser::Impossible<Self::Ok, Self::Error>; + __serialize_unimplemented_method!(serialize_struct(&str, usize) -> SerializeStruct); + }; + (struct_variant) => { + type SerializeStructVariant = $crate::ser::Impossible<Self::Ok, Self::Error>; + __serialize_unimplemented_method!(serialize_struct_variant(&str, u32, &str, usize) -> SerializeStructVariant); + }; +} diff --git a/src/private/mod.rs b/src/private/mod.rs new file mode 100644 index 0000000..e896902 --- /dev/null +++ b/src/private/mod.rs @@ -0,0 +1,50 @@ +#[cfg(not(no_serde_derive))] +pub mod de; +#[cfg(not(no_serde_derive))] +pub mod ser; + +pub mod size_hint; + +// FIXME: #[cfg(doctest)] once https://github.com/rust-lang/rust/issues/67295 is fixed. +pub mod doc; + +pub use lib::clone::Clone; +pub use lib::convert::{From, Into}; +pub use lib::default::Default; +pub use lib::fmt::{self, Formatter}; +pub use lib::marker::PhantomData; +pub use lib::option::Option::{self, None, Some}; +pub use lib::ptr; +pub use lib::result::Result::{self, Err, Ok}; + +pub use self::string::from_utf8_lossy; + +#[cfg(any(feature = "alloc", feature = "std"))] +pub use lib::{ToString, Vec}; + +#[cfg(not(no_core_try_from))] +pub use lib::convert::TryFrom; + +mod string { + use lib::*; + + #[cfg(any(feature = "std", feature = "alloc"))] + pub fn from_utf8_lossy(bytes: &[u8]) -> Cow<str> { + String::from_utf8_lossy(bytes) + } + + // The generated code calls this like: + // + // let value = &_serde::__private::from_utf8_lossy(bytes); + // Err(_serde::de::Error::unknown_variant(value, VARIANTS)) + // + // so it is okay for the return type to be different from the std case as long + // as the above works. + #[cfg(not(any(feature = "std", feature = "alloc")))] + pub fn from_utf8_lossy(bytes: &[u8]) -> &str { + // Three unicode replacement characters if it fails. They look like a + // white-on-black question mark. The user will recognize it as invalid + // UTF-8. + str::from_utf8(bytes).unwrap_or("\u{fffd}\u{fffd}\u{fffd}") + } +} diff --git a/src/private/ser.rs b/src/private/ser.rs new file mode 100644 index 0000000..528e8c1 --- /dev/null +++ b/src/private/ser.rs @@ -0,0 +1,1310 @@ +use lib::*; + +use ser::{self, Impossible, Serialize, SerializeMap, SerializeStruct, Serializer}; + +#[cfg(any(feature = "std", feature = "alloc"))] +use self::content::{ + Content, ContentSerializer, SerializeStructVariantAsMapValue, SerializeTupleVariantAsMapValue, +}; + +/// Used to check that serde(getter) attributes return the expected type. +/// Not public API. +pub fn constrain<T: ?Sized>(t: &T) -> &T { + t +} + +/// Not public API. +pub fn serialize_tagged_newtype<S, T>( + serializer: S, + type_ident: &'static str, + variant_ident: &'static str, + tag: &'static str, + variant_name: &'static str, + value: &T, +) -> Result<S::Ok, S::Error> +where + S: Serializer, + T: Serialize, +{ + value.serialize(TaggedSerializer { + type_ident: type_ident, + variant_ident: variant_ident, + tag: tag, + variant_name: variant_name, + delegate: serializer, + }) +} + +struct TaggedSerializer<S> { + type_ident: &'static str, + variant_ident: &'static str, + tag: &'static str, + variant_name: &'static str, + delegate: S, +} + +enum Unsupported { + Boolean, + Integer, + Float, + Char, + String, + ByteArray, + Optional, + #[cfg(any(feature = "std", feature = "alloc"))] + UnitStruct, + Sequence, + Tuple, + TupleStruct, + Enum, +} + +impl Display for Unsupported { + fn fmt(&self, formatter: &mut fmt::Formatter) -> fmt::Result { + match *self { + Unsupported::Boolean => formatter.write_str("a boolean"), + Unsupported::Integer => formatter.write_str("an integer"), + Unsupported::Float => formatter.write_str("a float"), + Unsupported::Char => formatter.write_str("a char"), + Unsupported::String => formatter.write_str("a string"), + Unsupported::ByteArray => formatter.write_str("a byte array"), + Unsupported::Optional => formatter.write_str("an optional"), + #[cfg(any(feature = "std", feature = "alloc"))] + Unsupported::UnitStruct => formatter.write_str("unit struct"), + Unsupported::Sequence => formatter.write_str("a sequence"), + Unsupported::Tuple => formatter.write_str("a tuple"), + Unsupported::TupleStruct => formatter.write_str("a tuple struct"), + Unsupported::Enum => formatter.write_str("an enum"), + } + } +} + +impl<S> TaggedSerializer<S> +where + S: Serializer, +{ + fn bad_type(self, what: Unsupported) -> S::Error { + ser::Error::custom(format_args!( + "cannot serialize tagged newtype variant {}::{} containing {}", + self.type_ident, self.variant_ident, what + )) + } +} + +impl<S> Serializer for TaggedSerializer<S> +where + S: Serializer, +{ + type Ok = S::Ok; + type Error = S::Error; + + type SerializeSeq = Impossible<S::Ok, S::Error>; + type SerializeTuple = Impossible<S::Ok, S::Error>; + type SerializeTupleStruct = Impossible<S::Ok, S::Error>; + type SerializeMap = S::SerializeMap; + type SerializeStruct = S::SerializeStruct; + + #[cfg(not(any(feature = "std", feature = "alloc")))] + type SerializeTupleVariant = Impossible<S::Ok, S::Error>; + #[cfg(any(feature = "std", feature = "alloc"))] + type SerializeTupleVariant = SerializeTupleVariantAsMapValue<S::SerializeMap>; + + #[cfg(not(any(feature = "std", feature = "alloc")))] + type SerializeStructVariant = Impossible<S::Ok, S::Error>; + #[cfg(any(feature = "std", feature = "alloc"))] + type SerializeStructVariant = SerializeStructVariantAsMapValue<S::SerializeMap>; + + fn serialize_bool(self, _: bool) -> Result<Self::Ok, Self::Error> { + Err(self.bad_type(Unsupported::Boolean)) + } + + fn serialize_i8(self, _: i8) -> Result<Self::Ok, Self::Error> { + Err(self.bad_type(Unsupported::Integer)) + } + + fn serialize_i16(self, _: i16) -> Result<Self::Ok, Self::Error> { + Err(self.bad_type(Unsupported::Integer)) + } + + fn serialize_i32(self, _: i32) -> Result<Self::Ok, Self::Error> { + Err(self.bad_type(Unsupported::Integer)) + } + + fn serialize_i64(self, _: i64) -> Result<Self::Ok, Self::Error> { + Err(self.bad_type(Unsupported::Integer)) + } + + fn serialize_u8(self, _: u8) -> Result<Self::Ok, Self::Error> { + Err(self.bad_type(Unsupported::Integer)) + } + + fn serialize_u16(self, _: u16) -> Result<Self::Ok, Self::Error> { + Err(self.bad_type(Unsupported::Integer)) + } + + fn serialize_u32(self, _: u32) -> Result<Self::Ok, Self::Error> { + Err(self.bad_type(Unsupported::Integer)) + } + + fn serialize_u64(self, _: u64) -> Result<Self::Ok, Self::Error> { + Err(self.bad_type(Unsupported::Integer)) + } + + fn serialize_f32(self, _: f32) -> Result<Self::Ok, Self::Error> { + Err(self.bad_type(Unsupported::Float)) + } + + fn serialize_f64(self, _: f64) -> Result<Self::Ok, Self::Error> { + Err(self.bad_type(Unsupported::Float)) + } + + fn serialize_char(self, _: char) -> Result<Self::Ok, Self::Error> { + Err(self.bad_type(Unsupported::Char)) + } + + fn serialize_str(self, _: &str) -> Result<Self::Ok, Self::Error> { + Err(self.bad_type(Unsupported::String)) + } + + fn serialize_bytes(self, _: &[u8]) -> Result<Self::Ok, Self::Error> { + Err(self.bad_type(Unsupported::ByteArray)) + } + + fn serialize_none(self) -> Result<Self::Ok, Self::Error> { + Err(self.bad_type(Unsupported::Optional)) + } + + fn serialize_some<T: ?Sized>(self, _: &T) -> Result<Self::Ok, Self::Error> + where + T: Serialize, + { + Err(self.bad_type(Unsupported::Optional)) + } + + fn serialize_unit(self) -> Result<Self::Ok, Self::Error> { + let mut map = try!(self.delegate.serialize_map(Some(1))); + try!(map.serialize_entry(self.tag, self.variant_name)); + map.end() + } + + fn serialize_unit_struct(self, _: &'static str) -> Result<Self::Ok, Self::Error> { + let mut map = try!(self.delegate.serialize_map(Some(1))); + try!(map.serialize_entry(self.tag, self.variant_name)); + map.end() + } + + fn serialize_unit_variant( + self, + _: &'static str, + _: u32, + inner_variant: &'static str, + ) -> Result<Self::Ok, Self::Error> { + let mut map = try!(self.delegate.serialize_map(Some(2))); + try!(map.serialize_entry(self.tag, self.variant_name)); + try!(map.serialize_entry(inner_variant, &())); + map.end() + } + + fn serialize_newtype_struct<T: ?Sized>( + self, + _: &'static str, + value: &T, + ) -> Result<Self::Ok, Self::Error> + where + T: Serialize, + { + value.serialize(self) + } + + fn serialize_newtype_variant<T: ?Sized>( + self, + _: &'static str, + _: u32, + inner_variant: &'static str, + inner_value: &T, + ) -> Result<Self::Ok, Self::Error> + where + T: Serialize, + { + let mut map = try!(self.delegate.serialize_map(Some(2))); + try!(map.serialize_entry(self.tag, self.variant_name)); + try!(map.serialize_entry(inner_variant, inner_value)); + map.end() + } + + fn serialize_seq(self, _: Option<usize>) -> Result<Self::SerializeSeq, Self::Error> { + Err(self.bad_type(Unsupported::Sequence)) + } + + fn serialize_tuple(self, _: usize) -> Result<Self::SerializeTuple, Self::Error> { + Err(self.bad_type(Unsupported::Tuple)) + } + + fn serialize_tuple_struct( + self, + _: &'static str, + _: usize, + ) -> Result<Self::SerializeTupleStruct, Self::Error> { + Err(self.bad_type(Unsupported::TupleStruct)) + } + + #[cfg(not(any(feature = "std", feature = "alloc")))] + fn serialize_tuple_variant( + self, + _: &'static str, + _: u32, + _: &'static str, + _: usize, + ) -> Result<Self::SerializeTupleVariant, Self::Error> { + // Lack of push-based serialization means we need to buffer the content + // of the tuple variant, so it requires std. + Err(self.bad_type(Unsupported::Enum)) + } + + #[cfg(any(feature = "std", feature = "alloc"))] + fn serialize_tuple_variant( + self, + _: &'static str, + _: u32, + inner_variant: &'static str, + len: usize, + ) -> Result<Self::SerializeTupleVariant, Self::Error> { + let mut map = try!(self.delegate.serialize_map(Some(2))); + try!(map.serialize_entry(self.tag, self.variant_name)); + try!(map.serialize_key(inner_variant)); + Ok(SerializeTupleVariantAsMapValue::new( + map, + inner_variant, + len, + )) + } + + fn serialize_map(self, len: Option<usize>) -> Result<Self::SerializeMap, Self::Error> { + let mut map = try!(self.delegate.serialize_map(len.map(|len| len + 1))); + try!(map.serialize_entry(self.tag, self.variant_name)); + Ok(map) + } + + fn serialize_struct( + self, + name: &'static str, + len: usize, + ) -> Result<Self::SerializeStruct, Self::Error> { + let mut state = try!(self.delegate.serialize_struct(name, len + 1)); + try!(state.serialize_field(self.tag, self.variant_name)); + Ok(state) + } + + #[cfg(not(any(feature = "std", feature = "alloc")))] + fn serialize_struct_variant( + self, + _: &'static str, + _: u32, + _: &'static str, + _: usize, + ) -> Result<Self::SerializeStructVariant, Self::Error> { + // Lack of push-based serialization means we need to buffer the content + // of the struct variant, so it requires std. + Err(self.bad_type(Unsupported::Enum)) + } + + #[cfg(any(feature = "std", feature = "alloc"))] + fn serialize_struct_variant( + self, + _: &'static str, + _: u32, + inner_variant: &'static str, + len: usize, + ) -> Result<Self::SerializeStructVariant, Self::Error> { + let mut map = try!(self.delegate.serialize_map(Some(2))); + try!(map.serialize_entry(self.tag, self.variant_name)); + try!(map.serialize_key(inner_variant)); + Ok(SerializeStructVariantAsMapValue::new( + map, + inner_variant, + len, + )) + } + + #[cfg(not(any(feature = "std", feature = "alloc")))] + fn collect_str<T: ?Sized>(self, _: &T) -> Result<Self::Ok, Self::Error> + where + T: Display, + { + Err(self.bad_type(Unsupported::String)) + } +} + +#[cfg(any(feature = "std", feature = "alloc"))] +mod content { + use lib::*; + + use ser::{self, Serialize, Serializer}; + + pub struct SerializeTupleVariantAsMapValue<M> { + map: M, + name: &'static str, + fields: Vec<Content>, + } + + impl<M> SerializeTupleVariantAsMapValue<M> { + pub fn new(map: M, name: &'static str, len: usize) -> Self { + SerializeTupleVariantAsMapValue { + map: map, + name: name, + fields: Vec::with_capacity(len), + } + } + } + + impl<M> ser::SerializeTupleVariant for SerializeTupleVariantAsMapValue<M> + where + M: ser::SerializeMap, + { + type Ok = M::Ok; + type Error = M::Error; + + fn serialize_field<T: ?Sized>(&mut self, value: &T) -> Result<(), M::Error> + where + T: Serialize, + { + let value = try!(value.serialize(ContentSerializer::<M::Error>::new())); + self.fields.push(value); + Ok(()) + } + + fn end(mut self) -> Result<M::Ok, M::Error> { + try!(self + .map + .serialize_value(&Content::TupleStruct(self.name, self.fields))); + self.map.end() + } + } + + pub struct SerializeStructVariantAsMapValue<M> { + map: M, + name: &'static str, + fields: Vec<(&'static str, Content)>, + } + + impl<M> SerializeStructVariantAsMapValue<M> { + pub fn new(map: M, name: &'static str, len: usize) -> Self { + SerializeStructVariantAsMapValue { + map: map, + name: name, + fields: Vec::with_capacity(len), + } + } + } + + impl<M> ser::SerializeStructVariant for SerializeStructVariantAsMapValue<M> + where + M: ser::SerializeMap, + { + type Ok = M::Ok; + type Error = M::Error; + + fn serialize_field<T: ?Sized>( + &mut self, + key: &'static str, + value: &T, + ) -> Result<(), M::Error> + where + T: Serialize, + { + let value = try!(value.serialize(ContentSerializer::<M::Error>::new())); + self.fields.push((key, value)); + Ok(()) + } + + fn end(mut self) -> Result<M::Ok, M::Error> { + try!(self + .map + .serialize_value(&Content::Struct(self.name, self.fields))); + self.map.end() + } + } + + pub enum Content { + Bool(bool), + + U8(u8), + U16(u16), + U32(u32), + U64(u64), + + I8(i8), + I16(i16), + I32(i32), + I64(i64), + + F32(f32), + F64(f64), + + Char(char), + String(String), + Bytes(Vec<u8>), + + None, + Some(Box<Content>), + + Unit, + UnitStruct(&'static str), + UnitVariant(&'static str, u32, &'static str), + NewtypeStruct(&'static str, Box<Content>), + NewtypeVariant(&'static str, u32, &'static str, Box<Content>), + + Seq(Vec<Content>), + Tuple(Vec<Content>), + TupleStruct(&'static str, Vec<Content>), + TupleVariant(&'static str, u32, &'static str, Vec<Content>), + Map(Vec<(Content, Content)>), + Struct(&'static str, Vec<(&'static str, Content)>), + StructVariant( + &'static str, + u32, + &'static str, + Vec<(&'static str, Content)>, + ), + } + + impl Serialize for Content { + fn serialize<S>(&self, serializer: S) -> Result<S::Ok, S::Error> + where + S: Serializer, + { + match *self { + Content::Bool(b) => serializer.serialize_bool(b), + Content::U8(u) => serializer.serialize_u8(u), + Content::U16(u) => serializer.serialize_u16(u), + Content::U32(u) => serializer.serialize_u32(u), + Content::U64(u) => serializer.serialize_u64(u), + Content::I8(i) => serializer.serialize_i8(i), + Content::I16(i) => serializer.serialize_i16(i), + Content::I32(i) => serializer.serialize_i32(i), + Content::I64(i) => serializer.serialize_i64(i), + Content::F32(f) => serializer.serialize_f32(f), + Content::F64(f) => serializer.serialize_f64(f), + Content::Char(c) => serializer.serialize_char(c), + Content::String(ref s) => serializer.serialize_str(s), + Content::Bytes(ref b) => serializer.serialize_bytes(b), + Content::None => serializer.serialize_none(), + Content::Some(ref c) => serializer.serialize_some(&**c), + Content::Unit => serializer.serialize_unit(), + Content::UnitStruct(n) => serializer.serialize_unit_struct(n), + Content::UnitVariant(n, i, v) => serializer.serialize_unit_variant(n, i, v), + Content::NewtypeStruct(n, ref c) => serializer.serialize_newtype_struct(n, &**c), + Content::NewtypeVariant(n, i, v, ref c) => { + serializer.serialize_newtype_variant(n, i, v, &**c) + } + Content::Seq(ref elements) => elements.serialize(serializer), + Content::Tuple(ref elements) => { + use ser::SerializeTuple; + let mut tuple = try!(serializer.serialize_tuple(elements.len())); + for e in elements { + try!(tuple.serialize_element(e)); + } + tuple.end() + } + Content::TupleStruct(n, ref fields) => { + use ser::SerializeTupleStruct; + let mut ts = try!(serializer.serialize_tuple_struct(n, fields.len())); + for f in fields { + try!(ts.serialize_field(f)); + } + ts.end() + } + Content::TupleVariant(n, i, v, ref fields) => { + use ser::SerializeTupleVariant; + let mut tv = try!(serializer.serialize_tuple_variant(n, i, v, fields.len())); + for f in fields { + try!(tv.serialize_field(f)); + } + tv.end() + } + Content::Map(ref entries) => { + use ser::SerializeMap; + let mut map = try!(serializer.serialize_map(Some(entries.len()))); + for (k, v) in entries { + try!(map.serialize_entry(k, v)); + } + map.end() + } + Content::Struct(n, ref fields) => { + use ser::SerializeStruct; + let mut s = try!(serializer.serialize_struct(n, fields.len())); + for &(k, ref v) in fields { + try!(s.serialize_field(k, v)); + } + s.end() + } + Content::StructVariant(n, i, v, ref fields) => { + use ser::SerializeStructVariant; + let mut sv = try!(serializer.serialize_struct_variant(n, i, v, fields.len())); + for &(k, ref v) in fields { + try!(sv.serialize_field(k, v)); + } + sv.end() + } + } + } + } + + pub struct ContentSerializer<E> { + error: PhantomData<E>, + } + + impl<E> ContentSerializer<E> { + pub fn new() -> Self { + ContentSerializer { error: PhantomData } + } + } + + impl<E> Serializer for ContentSerializer<E> + where + E: ser::Error, + { + type Ok = Content; + type Error = E; + + type SerializeSeq = SerializeSeq<E>; + type SerializeTuple = SerializeTuple<E>; + type SerializeTupleStruct = SerializeTupleStruct<E>; + type SerializeTupleVariant = SerializeTupleVariant<E>; + type SerializeMap = SerializeMap<E>; + type SerializeStruct = SerializeStruct<E>; + type SerializeStructVariant = SerializeStructVariant<E>; + + fn serialize_bool(self, v: bool) -> Result<Content, E> { + Ok(Content::Bool(v)) + } + + fn serialize_i8(self, v: i8) -> Result<Content, E> { + Ok(Content::I8(v)) + } + + fn serialize_i16(self, v: i16) -> Result<Content, E> { + Ok(Content::I16(v)) + } + + fn serialize_i32(self, v: i32) -> Result<Content, E> { + Ok(Content::I32(v)) + } + + fn serialize_i64(self, v: i64) -> Result<Content, E> { + Ok(Content::I64(v)) + } + + fn serialize_u8(self, v: u8) -> Result<Content, E> { + Ok(Content::U8(v)) + } + + fn serialize_u16(self, v: u16) -> Result<Content, E> { + Ok(Content::U16(v)) + } + + fn serialize_u32(self, v: u32) -> Result<Content, E> { + Ok(Content::U32(v)) + } + + fn serialize_u64(self, v: u64) -> Result<Content, E> { + Ok(Content::U64(v)) + } + + fn serialize_f32(self, v: f32) -> Result<Content, E> { + Ok(Content::F32(v)) + } + + fn serialize_f64(self, v: f64) -> Result<Content, E> { + Ok(Content::F64(v)) + } + + fn serialize_char(self, v: char) -> Result<Content, E> { + Ok(Content::Char(v)) + } + + fn serialize_str(self, value: &str) -> Result<Content, E> { + Ok(Content::String(value.to_owned())) + } + + fn serialize_bytes(self, value: &[u8]) -> Result<Content, E> { + Ok(Content::Bytes(value.to_owned())) + } + + fn serialize_none(self) -> Result<Content, E> { + Ok(Content::None) + } + + fn serialize_some<T: ?Sized>(self, value: &T) -> Result<Content, E> + where + T: Serialize, + { + Ok(Content::Some(Box::new(try!(value.serialize(self))))) + } + + fn serialize_unit(self) -> Result<Content, E> { + Ok(Content::Unit) + } + + fn serialize_unit_struct(self, name: &'static str) -> Result<Content, E> { + Ok(Content::UnitStruct(name)) + } + + fn serialize_unit_variant( + self, + name: &'static str, + variant_index: u32, + variant: &'static str, + ) -> Result<Content, E> { + Ok(Content::UnitVariant(name, variant_index, variant)) + } + + fn serialize_newtype_struct<T: ?Sized>( + self, + name: &'static str, + value: &T, + ) -> Result<Content, E> + where + T: Serialize, + { + Ok(Content::NewtypeStruct( + name, + Box::new(try!(value.serialize(self))), + )) + } + + fn serialize_newtype_variant<T: ?Sized>( + self, + name: &'static str, + variant_index: u32, + variant: &'static str, + value: &T, + ) -> Result<Content, E> + where + T: Serialize, + { + Ok(Content::NewtypeVariant( + name, + variant_index, + variant, + Box::new(try!(value.serialize(self))), + )) + } + + fn serialize_seq(self, len: Option<usize>) -> Result<Self::SerializeSeq, E> { + Ok(SerializeSeq { + elements: Vec::with_capacity(len.unwrap_or(0)), + error: PhantomData, + }) + } + + fn serialize_tuple(self, len: usize) -> Result<Self::SerializeTuple, E> { + Ok(SerializeTuple { + elements: Vec::with_capacity(len), + error: PhantomData, + }) + } + + fn serialize_tuple_struct( + self, + name: &'static str, + len: usize, + ) -> Result<Self::SerializeTupleStruct, E> { + Ok(SerializeTupleStruct { + name: name, + fields: Vec::with_capacity(len), + error: PhantomData, + }) + } + + fn serialize_tuple_variant( + self, + name: &'static str, + variant_index: u32, + variant: &'static str, + len: usize, + ) -> Result<Self::SerializeTupleVariant, E> { + Ok(SerializeTupleVariant { + name: name, + variant_index: variant_index, + variant: variant, + fields: Vec::with_capacity(len), + error: PhantomData, + }) + } + + fn serialize_map(self, len: Option<usize>) -> Result<Self::SerializeMap, E> { + Ok(SerializeMap { + entries: Vec::with_capacity(len.unwrap_or(0)), + key: None, + error: PhantomData, + }) + } + + fn serialize_struct( + self, + name: &'static str, + len: usize, + ) -> Result<Self::SerializeStruct, E> { + Ok(SerializeStruct { + name: name, + fields: Vec::with_capacity(len), + error: PhantomData, + }) + } + + fn serialize_struct_variant( + self, + name: &'static str, + variant_index: u32, + variant: &'static str, + len: usize, + ) -> Result<Self::SerializeStructVariant, E> { + Ok(SerializeStructVariant { + name: name, + variant_index: variant_index, + variant: variant, + fields: Vec::with_capacity(len), + error: PhantomData, + }) + } + } + + pub struct SerializeSeq<E> { + elements: Vec<Content>, + error: PhantomData<E>, + } + + impl<E> ser::SerializeSeq for SerializeSeq<E> + where + E: ser::Error, + { + type Ok = Content; + type Error = E; + + fn serialize_element<T: ?Sized>(&mut self, value: &T) -> Result<(), E> + where + T: Serialize, + { + let value = try!(value.serialize(ContentSerializer::<E>::new())); + self.elements.push(value); + Ok(()) + } + + fn end(self) -> Result<Content, E> { + Ok(Content::Seq(self.elements)) + } + } + + pub struct SerializeTuple<E> { + elements: Vec<Content>, + error: PhantomData<E>, + } + + impl<E> ser::SerializeTuple for SerializeTuple<E> + where + E: ser::Error, + { + type Ok = Content; + type Error = E; + + fn serialize_element<T: ?Sized>(&mut self, value: &T) -> Result<(), E> + where + T: Serialize, + { + let value = try!(value.serialize(ContentSerializer::<E>::new())); + self.elements.push(value); + Ok(()) + } + + fn end(self) -> Result<Content, E> { + Ok(Content::Tuple(self.elements)) + } + } + + pub struct SerializeTupleStruct<E> { + name: &'static str, + fields: Vec<Content>, + error: PhantomData<E>, + } + + impl<E> ser::SerializeTupleStruct for SerializeTupleStruct<E> + where + E: ser::Error, + { + type Ok = Content; + type Error = E; + + fn serialize_field<T: ?Sized>(&mut self, value: &T) -> Result<(), E> + where + T: Serialize, + { + let value = try!(value.serialize(ContentSerializer::<E>::new())); + self.fields.push(value); + Ok(()) + } + + fn end(self) -> Result<Content, E> { + Ok(Content::TupleStruct(self.name, self.fields)) + } + } + + pub struct SerializeTupleVariant<E> { + name: &'static str, + variant_index: u32, + variant: &'static str, + fields: Vec<Content>, + error: PhantomData<E>, + } + + impl<E> ser::SerializeTupleVariant for SerializeTupleVariant<E> + where + E: ser::Error, + { + type Ok = Content; + type Error = E; + + fn serialize_field<T: ?Sized>(&mut self, value: &T) -> Result<(), E> + where + T: Serialize, + { + let value = try!(value.serialize(ContentSerializer::<E>::new())); + self.fields.push(value); + Ok(()) + } + + fn end(self) -> Result<Content, E> { + Ok(Content::TupleVariant( + self.name, + self.variant_index, + self.variant, + self.fields, + )) + } + } + + pub struct SerializeMap<E> { + entries: Vec<(Content, Content)>, + key: Option<Content>, + error: PhantomData<E>, + } + + impl<E> ser::SerializeMap for SerializeMap<E> + where + E: ser::Error, + { + type Ok = Content; + type Error = E; + + fn serialize_key<T: ?Sized>(&mut self, key: &T) -> Result<(), E> + where + T: Serialize, + { + let key = try!(key.serialize(ContentSerializer::<E>::new())); + self.key = Some(key); + Ok(()) + } + + fn serialize_value<T: ?Sized>(&mut self, value: &T) -> Result<(), E> + where + T: Serialize, + { + let key = self + .key + .take() + .expect("serialize_value called before serialize_key"); + let value = try!(value.serialize(ContentSerializer::<E>::new())); + self.entries.push((key, value)); + Ok(()) + } + + fn end(self) -> Result<Content, E> { + Ok(Content::Map(self.entries)) + } + + fn serialize_entry<K: ?Sized, V: ?Sized>(&mut self, key: &K, value: &V) -> Result<(), E> + where + K: Serialize, + V: Serialize, + { + let key = try!(key.serialize(ContentSerializer::<E>::new())); + let value = try!(value.serialize(ContentSerializer::<E>::new())); + self.entries.push((key, value)); + Ok(()) + } + } + + pub struct SerializeStruct<E> { + name: &'static str, + fields: Vec<(&'static str, Content)>, + error: PhantomData<E>, + } + + impl<E> ser::SerializeStruct for SerializeStruct<E> + where + E: ser::Error, + { + type Ok = Content; + type Error = E; + + fn serialize_field<T: ?Sized>(&mut self, key: &'static str, value: &T) -> Result<(), E> + where + T: Serialize, + { + let value = try!(value.serialize(ContentSerializer::<E>::new())); + self.fields.push((key, value)); + Ok(()) + } + + fn end(self) -> Result<Content, E> { + Ok(Content::Struct(self.name, self.fields)) + } + } + + pub struct SerializeStructVariant<E> { + name: &'static str, + variant_index: u32, + variant: &'static str, + fields: Vec<(&'static str, Content)>, + error: PhantomData<E>, + } + + impl<E> ser::SerializeStructVariant for SerializeStructVariant<E> + where + E: ser::Error, + { + type Ok = Content; + type Error = E; + + fn serialize_field<T: ?Sized>(&mut self, key: &'static str, value: &T) -> Result<(), E> + where + T: Serialize, + { + let value = try!(value.serialize(ContentSerializer::<E>::new())); + self.fields.push((key, value)); + Ok(()) + } + + fn end(self) -> Result<Content, E> { + Ok(Content::StructVariant( + self.name, + self.variant_index, + self.variant, + self.fields, + )) + } + } +} + +#[cfg(any(feature = "std", feature = "alloc"))] +pub struct FlatMapSerializer<'a, M: 'a>(pub &'a mut M); + +#[cfg(any(feature = "std", feature = "alloc"))] +impl<'a, M> FlatMapSerializer<'a, M> +where + M: SerializeMap + 'a, +{ + fn bad_type(what: Unsupported) -> M::Error { + ser::Error::custom(format_args!( + "can only flatten structs and maps (got {})", + what + )) + } +} + +#[cfg(any(feature = "std", feature = "alloc"))] +impl<'a, M> Serializer for FlatMapSerializer<'a, M> +where + M: SerializeMap + 'a, +{ + type Ok = (); + type Error = M::Error; + + type SerializeSeq = Impossible<Self::Ok, M::Error>; + type SerializeTuple = Impossible<Self::Ok, M::Error>; + type SerializeTupleStruct = Impossible<Self::Ok, M::Error>; + type SerializeMap = FlatMapSerializeMap<'a, M>; + type SerializeStruct = FlatMapSerializeStruct<'a, M>; + type SerializeTupleVariant = Impossible<Self::Ok, M::Error>; + type SerializeStructVariant = FlatMapSerializeStructVariantAsMapValue<'a, M>; + + fn serialize_bool(self, _: bool) -> Result<Self::Ok, Self::Error> { + Err(Self::bad_type(Unsupported::Boolean)) + } + + fn serialize_i8(self, _: i8) -> Result<Self::Ok, Self::Error> { + Err(Self::bad_type(Unsupported::Integer)) + } + + fn serialize_i16(self, _: i16) -> Result<Self::Ok, Self::Error> { + Err(Self::bad_type(Unsupported::Integer)) + } + + fn serialize_i32(self, _: i32) -> Result<Self::Ok, Self::Error> { + Err(Self::bad_type(Unsupported::Integer)) + } + + fn serialize_i64(self, _: i64) -> Result<Self::Ok, Self::Error> { + Err(Self::bad_type(Unsupported::Integer)) + } + + fn serialize_u8(self, _: u8) -> Result<Self::Ok, Self::Error> { + Err(Self::bad_type(Unsupported::Integer)) + } + + fn serialize_u16(self, _: u16) -> Result<Self::Ok, Self::Error> { + Err(Self::bad_type(Unsupported::Integer)) + } + + fn serialize_u32(self, _: u32) -> Result<Self::Ok, Self::Error> { + Err(Self::bad_type(Unsupported::Integer)) + } + + fn serialize_u64(self, _: u64) -> Result<Self::Ok, Self::Error> { + Err(Self::bad_type(Unsupported::Integer)) + } + + fn serialize_f32(self, _: f32) -> Result<Self::Ok, Self::Error> { + Err(Self::bad_type(Unsupported::Float)) + } + + fn serialize_f64(self, _: f64) -> Result<Self::Ok, Self::Error> { + Err(Self::bad_type(Unsupported::Float)) + } + + fn serialize_char(self, _: char) -> Result<Self::Ok, Self::Error> { + Err(Self::bad_type(Unsupported::Char)) + } + + fn serialize_str(self, _: &str) -> Result<Self::Ok, Self::Error> { + Err(Self::bad_type(Unsupported::String)) + } + + fn serialize_bytes(self, _: &[u8]) -> Result<Self::Ok, Self::Error> { + Err(Self::bad_type(Unsupported::ByteArray)) + } + + fn serialize_none(self) -> Result<Self::Ok, Self::Error> { + Ok(()) + } + + fn serialize_some<T: ?Sized>(self, value: &T) -> Result<Self::Ok, Self::Error> + where + T: Serialize, + { + value.serialize(self) + } + + fn serialize_unit(self) -> Result<Self::Ok, Self::Error> { + Ok(()) + } + + fn serialize_unit_struct(self, _: &'static str) -> Result<Self::Ok, Self::Error> { + Err(Self::bad_type(Unsupported::UnitStruct)) + } + + fn serialize_unit_variant( + self, + _: &'static str, + _: u32, + _: &'static str, + ) -> Result<Self::Ok, Self::Error> { + Err(Self::bad_type(Unsupported::Enum)) + } + + fn serialize_newtype_struct<T: ?Sized>( + self, + _: &'static str, + value: &T, + ) -> Result<Self::Ok, Self::Error> + where + T: Serialize, + { + value.serialize(self) + } + + fn serialize_newtype_variant<T: ?Sized>( + self, + _: &'static str, + _: u32, + variant: &'static str, + value: &T, + ) -> Result<Self::Ok, Self::Error> + where + T: Serialize, + { + try!(self.0.serialize_key(variant)); + self.0.serialize_value(value) + } + + fn serialize_seq(self, _: Option<usize>) -> Result<Self::SerializeSeq, Self::Error> { + Err(Self::bad_type(Unsupported::Sequence)) + } + + fn serialize_tuple(self, _: usize) -> Result<Self::SerializeTuple, Self::Error> { + Err(Self::bad_type(Unsupported::Tuple)) + } + + fn serialize_tuple_struct( + self, + _: &'static str, + _: usize, + ) -> Result<Self::SerializeTupleStruct, Self::Error> { + Err(Self::bad_type(Unsupported::TupleStruct)) + } + + fn serialize_tuple_variant( + self, + _: &'static str, + _: u32, + _: &'static str, + _: usize, + ) -> Result<Self::SerializeTupleVariant, Self::Error> { + Err(Self::bad_type(Unsupported::Enum)) + } + + fn serialize_map(self, _: Option<usize>) -> Result<Self::SerializeMap, Self::Error> { + Ok(FlatMapSerializeMap(self.0)) + } + + fn serialize_struct( + self, + _: &'static str, + _: usize, + ) -> Result<Self::SerializeStruct, Self::Error> { + Ok(FlatMapSerializeStruct(self.0)) + } + + fn serialize_struct_variant( + self, + _: &'static str, + _: u32, + inner_variant: &'static str, + _: usize, + ) -> Result<Self::SerializeStructVariant, Self::Error> { + try!(self.0.serialize_key(inner_variant)); + Ok(FlatMapSerializeStructVariantAsMapValue::new( + self.0, + inner_variant, + )) + } +} + +#[cfg(any(feature = "std", feature = "alloc"))] +pub struct FlatMapSerializeMap<'a, M: 'a>(&'a mut M); + +#[cfg(any(feature = "std", feature = "alloc"))] +impl<'a, M> ser::SerializeMap for FlatMapSerializeMap<'a, M> +where + M: SerializeMap + 'a, +{ + type Ok = (); + type Error = M::Error; + + fn serialize_key<T: ?Sized>(&mut self, key: &T) -> Result<(), Self::Error> + where + T: Serialize, + { + self.0.serialize_key(key) + } + + fn serialize_value<T: ?Sized>(&mut self, value: &T) -> Result<(), Self::Error> + where + T: Serialize, + { + self.0.serialize_value(value) + } + + fn serialize_entry<K: ?Sized, V: ?Sized>( + &mut self, + key: &K, + value: &V, + ) -> Result<(), Self::Error> + where + K: Serialize, + V: Serialize, + { + self.0.serialize_entry(key, value) + } + + fn end(self) -> Result<(), Self::Error> { + Ok(()) + } +} + +#[cfg(any(feature = "std", feature = "alloc"))] +pub struct FlatMapSerializeStruct<'a, M: 'a>(&'a mut M); + +#[cfg(any(feature = "std", feature = "alloc"))] +impl<'a, M> ser::SerializeStruct for FlatMapSerializeStruct<'a, M> +where + M: SerializeMap + 'a, +{ + type Ok = (); + type Error = M::Error; + + fn serialize_field<T: ?Sized>( + &mut self, + key: &'static str, + value: &T, + ) -> Result<(), Self::Error> + where + T: Serialize, + { + self.0.serialize_entry(key, value) + } + + fn end(self) -> Result<(), Self::Error> { + Ok(()) + } +} + +#[cfg(any(feature = "std", feature = "alloc"))] +pub struct FlatMapSerializeStructVariantAsMapValue<'a, M: 'a> { + map: &'a mut M, + name: &'static str, + fields: Vec<(&'static str, Content)>, +} + +#[cfg(any(feature = "std", feature = "alloc"))] +impl<'a, M> FlatMapSerializeStructVariantAsMapValue<'a, M> +where + M: SerializeMap + 'a, +{ + fn new(map: &'a mut M, name: &'static str) -> FlatMapSerializeStructVariantAsMapValue<'a, M> { + FlatMapSerializeStructVariantAsMapValue { + map: map, + name: name, + fields: Vec::new(), + } + } +} + +#[cfg(any(feature = "std", feature = "alloc"))] +impl<'a, M> ser::SerializeStructVariant for FlatMapSerializeStructVariantAsMapValue<'a, M> +where + M: SerializeMap + 'a, +{ + type Ok = (); + type Error = M::Error; + + fn serialize_field<T: ?Sized>( + &mut self, + key: &'static str, + value: &T, + ) -> Result<(), Self::Error> + where + T: Serialize, + { + let value = try!(value.serialize(ContentSerializer::<M::Error>::new())); + self.fields.push((key, value)); + Ok(()) + } + + fn end(self) -> Result<(), Self::Error> { + try!(self + .map + .serialize_value(&Content::Struct(self.name, self.fields))); + Ok(()) + } +} diff --git a/src/private/size_hint.rs b/src/private/size_hint.rs new file mode 100644 index 0000000..ca71e61 --- /dev/null +++ b/src/private/size_hint.rs @@ -0,0 +1,21 @@ +use lib::*; + +pub fn from_bounds<I>(iter: &I) -> Option<usize> +where + I: Iterator, +{ + helper(iter.size_hint()) +} + +#[cfg(any(feature = "std", feature = "alloc"))] +#[inline] +pub fn cautious(hint: Option<usize>) -> usize { + cmp::min(hint.unwrap_or(0), 4096) +} + +fn helper(bounds: (usize, Option<usize>)) -> Option<usize> { + match bounds { + (lower, Some(upper)) if lower == upper => Some(upper), + _ => None, + } +} diff --git a/src/ser/fmt.rs b/src/ser/fmt.rs new file mode 100644 index 0000000..e7e09a1 --- /dev/null +++ b/src/ser/fmt.rs @@ -0,0 +1,174 @@ +use lib::*; +use ser::{Error, Impossible, Serialize, Serializer}; + +impl Error for fmt::Error { + fn custom<T: Display>(_msg: T) -> Self { + fmt::Error + } +} + +macro_rules! fmt_primitives { + ($($f:ident: $t:ty,)*) => { + $( + fn $f(self, v: $t) -> fmt::Result { + Display::fmt(&v, self) + } + )* + }; +} + +/// ```edition2018 +/// use serde::Serialize; +/// use std::fmt::{self, Display}; +/// +/// #[derive(Serialize)] +/// #[serde(rename_all = "kebab-case")] +/// pub enum MessageType { +/// StartRequest, +/// EndRequest, +/// } +/// +/// impl Display for MessageType { +/// fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result { +/// self.serialize(f) +/// } +/// } +/// ``` +impl<'a, 'b> Serializer for &'a mut fmt::Formatter<'b> { + type Ok = (); + type Error = fmt::Error; + type SerializeSeq = Impossible<(), fmt::Error>; + type SerializeTuple = Impossible<(), fmt::Error>; + type SerializeTupleStruct = Impossible<(), fmt::Error>; + type SerializeTupleVariant = Impossible<(), fmt::Error>; + type SerializeMap = Impossible<(), fmt::Error>; + type SerializeStruct = Impossible<(), fmt::Error>; + type SerializeStructVariant = Impossible<(), fmt::Error>; + + fmt_primitives! { + serialize_bool: bool, + serialize_i8: i8, + serialize_i16: i16, + serialize_i32: i32, + serialize_i64: i64, + serialize_u8: u8, + serialize_u16: u16, + serialize_u32: u32, + serialize_u64: u64, + serialize_f32: f32, + serialize_f64: f64, + serialize_char: char, + serialize_str: &str, + serialize_unit_struct: &'static str, + } + + serde_if_integer128! { + fmt_primitives! { + serialize_i128: i128, + serialize_u128: u128, + } + } + + fn serialize_unit_variant( + self, + _name: &'static str, + _variant_index: u32, + variant: &'static str, + ) -> fmt::Result { + Display::fmt(variant, self) + } + + fn serialize_newtype_struct<T: ?Sized>(self, _name: &'static str, value: &T) -> fmt::Result + where + T: Serialize, + { + Serialize::serialize(value, self) + } + + fn serialize_bytes(self, _v: &[u8]) -> fmt::Result { + Err(fmt::Error) + } + + fn serialize_none(self) -> fmt::Result { + Err(fmt::Error) + } + + fn serialize_some<T: ?Sized>(self, _value: &T) -> fmt::Result + where + T: Serialize, + { + Err(fmt::Error) + } + + fn serialize_unit(self) -> fmt::Result { + Err(fmt::Error) + } + + fn serialize_newtype_variant<T: ?Sized>( + self, + _name: &'static str, + _variant_index: u32, + _variant: &'static str, + _value: &T, + ) -> fmt::Result + where + T: Serialize, + { + Err(fmt::Error) + } + + fn serialize_seq(self, _len: Option<usize>) -> Result<Self::SerializeSeq, fmt::Error> { + Err(fmt::Error) + } + + fn serialize_tuple(self, _len: usize) -> Result<Self::SerializeTuple, fmt::Error> { + Err(fmt::Error) + } + + fn serialize_tuple_struct( + self, + _name: &'static str, + _len: usize, + ) -> Result<Self::SerializeTupleStruct, fmt::Error> { + Err(fmt::Error) + } + + fn serialize_tuple_variant( + self, + _name: &'static str, + _variant_index: u32, + _variant: &'static str, + _len: usize, + ) -> Result<Self::SerializeTupleVariant, fmt::Error> { + Err(fmt::Error) + } + + fn serialize_map(self, _len: Option<usize>) -> Result<Self::SerializeMap, fmt::Error> { + Err(fmt::Error) + } + + fn serialize_struct( + self, + _name: &'static str, + _len: usize, + ) -> Result<Self::SerializeStruct, fmt::Error> { + Err(fmt::Error) + } + + fn serialize_struct_variant( + self, + _name: &'static str, + _variant_index: u32, + _variant: &'static str, + _len: usize, + ) -> Result<Self::SerializeStructVariant, fmt::Error> { + Err(fmt::Error) + } + + fn collect_str<T: ?Sized>(self, value: &T) -> fmt::Result + where + T: Display, + { + Display::fmt(value, self) + } +} diff --git a/src/ser/impls.rs b/src/ser/impls.rs new file mode 100644 index 0000000..da26772 --- /dev/null +++ b/src/ser/impls.rs @@ -0,0 +1,983 @@ +use lib::*; + +use ser::{Error, Serialize, SerializeTuple, Serializer}; + +//////////////////////////////////////////////////////////////////////////////// + +macro_rules! primitive_impl { + ($ty:ident, $method:ident $($cast:tt)*) => { + impl Serialize for $ty { + #[inline] + fn serialize<S>(&self, serializer: S) -> Result<S::Ok, S::Error> + where + S: Serializer, + { + serializer.$method(*self $($cast)*) + } + } + } +} + +primitive_impl!(bool, serialize_bool); +primitive_impl!(isize, serialize_i64 as i64); +primitive_impl!(i8, serialize_i8); +primitive_impl!(i16, serialize_i16); +primitive_impl!(i32, serialize_i32); +primitive_impl!(i64, serialize_i64); +primitive_impl!(usize, serialize_u64 as u64); +primitive_impl!(u8, serialize_u8); +primitive_impl!(u16, serialize_u16); +primitive_impl!(u32, serialize_u32); +primitive_impl!(u64, serialize_u64); +primitive_impl!(f32, serialize_f32); +primitive_impl!(f64, serialize_f64); +primitive_impl!(char, serialize_char); + +serde_if_integer128! { + primitive_impl!(i128, serialize_i128); + primitive_impl!(u128, serialize_u128); +} + +//////////////////////////////////////////////////////////////////////////////// + +impl Serialize for str { + #[inline] + fn serialize<S>(&self, serializer: S) -> Result<S::Ok, S::Error> + where + S: Serializer, + { + serializer.serialize_str(self) + } +} + +#[cfg(any(feature = "std", feature = "alloc"))] +impl Serialize for String { + #[inline] + fn serialize<S>(&self, serializer: S) -> Result<S::Ok, S::Error> + where + S: Serializer, + { + serializer.serialize_str(self) + } +} + +impl<'a> Serialize for fmt::Arguments<'a> { + fn serialize<S>(&self, serializer: S) -> Result<S::Ok, S::Error> + where + S: Serializer, + { + serializer.collect_str(self) + } +} + +//////////////////////////////////////////////////////////////////////////////// + +#[cfg(feature = "std")] +impl Serialize for CStr { + #[inline] + fn serialize<S>(&self, serializer: S) -> Result<S::Ok, S::Error> + where + S: Serializer, + { + serializer.serialize_bytes(self.to_bytes()) + } +} + +#[cfg(feature = "std")] +impl Serialize for CString { + #[inline] + fn serialize<S>(&self, serializer: S) -> Result<S::Ok, S::Error> + where + S: Serializer, + { + serializer.serialize_bytes(self.to_bytes()) + } +} + +//////////////////////////////////////////////////////////////////////////////// + +impl<T> Serialize for Option<T> +where + T: Serialize, +{ + #[inline] + fn serialize<S>(&self, serializer: S) -> Result<S::Ok, S::Error> + where + S: Serializer, + { + match *self { + Some(ref value) => serializer.serialize_some(value), + None => serializer.serialize_none(), + } + } +} + +//////////////////////////////////////////////////////////////////////////////// + +impl<T: ?Sized> Serialize for PhantomData<T> { + #[inline] + fn serialize<S>(&self, serializer: S) -> Result<S::Ok, S::Error> + where + S: Serializer, + { + serializer.serialize_unit_struct("PhantomData") + } +} + +//////////////////////////////////////////////////////////////////////////////// + +// Does not require T: Serialize. +impl<T> Serialize for [T; 0] { + #[inline] + fn serialize<S>(&self, serializer: S) -> Result<S::Ok, S::Error> + where + S: Serializer, + { + try!(serializer.serialize_tuple(0)).end() + } +} + +macro_rules! array_impls { + ($($len:tt)+) => { + $( + impl<T> Serialize for [T; $len] + where + T: Serialize, + { + #[inline] + fn serialize<S>(&self, serializer: S) -> Result<S::Ok, S::Error> + where + S: Serializer, + { + let mut seq = try!(serializer.serialize_tuple($len)); + for e in self { + try!(seq.serialize_element(e)); + } + seq.end() + } + } + )+ + } +} + +array_impls! { + 01 02 03 04 05 06 07 08 09 10 + 11 12 13 14 15 16 17 18 19 20 + 21 22 23 24 25 26 27 28 29 30 + 31 32 +} + +//////////////////////////////////////////////////////////////////////////////// + +impl<T> Serialize for [T] +where + T: Serialize, +{ + #[inline] + fn serialize<S>(&self, serializer: S) -> Result<S::Ok, S::Error> + where + S: Serializer, + { + serializer.collect_seq(self) + } +} + +#[cfg(all(any(feature = "std", feature = "alloc"), not(no_relaxed_trait_bounds)))] +macro_rules! seq_impl { + ($ty:ident <T $(: $tbound1:ident $(+ $tbound2:ident)*)* $(, $typaram:ident : $bound:ident)*>) => { + impl<T $(, $typaram)*> Serialize for $ty<T $(, $typaram)*> + where + T: Serialize, + { + #[inline] + fn serialize<S>(&self, serializer: S) -> Result<S::Ok, S::Error> + where + S: Serializer, + { + serializer.collect_seq(self) + } + } + } +} + +#[cfg(all(any(feature = "std", feature = "alloc"), no_relaxed_trait_bounds))] +macro_rules! seq_impl { + ($ty:ident <T $(: $tbound1:ident $(+ $tbound2:ident)*)* $(, $typaram:ident : $bound:ident)*>) => { + impl<T $(, $typaram)*> Serialize for $ty<T $(, $typaram)*> + where + T: Serialize $(+ $tbound1 $(+ $tbound2)*)*, + $($typaram: $bound,)* + { + #[inline] + fn serialize<S>(&self, serializer: S) -> Result<S::Ok, S::Error> + where + S: Serializer, + { + serializer.collect_seq(self) + } + } + } +} + +#[cfg(any(feature = "std", feature = "alloc"))] +seq_impl!(BinaryHeap<T: Ord>); + +#[cfg(any(feature = "std", feature = "alloc"))] +seq_impl!(BTreeSet<T: Ord>); + +#[cfg(feature = "std")] +seq_impl!(HashSet<T: Eq + Hash, H: BuildHasher>); + +#[cfg(any(feature = "std", feature = "alloc"))] +seq_impl!(LinkedList<T>); + +#[cfg(any(feature = "std", feature = "alloc"))] +seq_impl!(Vec<T>); + +#[cfg(any(feature = "std", feature = "alloc"))] +seq_impl!(VecDeque<T>); + +//////////////////////////////////////////////////////////////////////////////// + +impl<Idx> Serialize for Range<Idx> +where + Idx: Serialize, +{ + fn serialize<S>(&self, serializer: S) -> Result<S::Ok, S::Error> + where + S: Serializer, + { + use super::SerializeStruct; + let mut state = try!(serializer.serialize_struct("Range", 2)); + try!(state.serialize_field("start", &self.start)); + try!(state.serialize_field("end", &self.end)); + state.end() + } +} + +//////////////////////////////////////////////////////////////////////////////// + +#[cfg(not(no_range_inclusive))] +impl<Idx> Serialize for RangeInclusive<Idx> +where + Idx: Serialize, +{ + fn serialize<S>(&self, serializer: S) -> Result<S::Ok, S::Error> + where + S: Serializer, + { + use super::SerializeStruct; + let mut state = try!(serializer.serialize_struct("RangeInclusive", 2)); + try!(state.serialize_field("start", &self.start())); + try!(state.serialize_field("end", &self.end())); + state.end() + } +} + +//////////////////////////////////////////////////////////////////////////////// + +#[cfg(any(not(no_ops_bound), all(feature = "std", not(no_collections_bound))))] +impl<T> Serialize for Bound<T> +where + T: Serialize, +{ + fn serialize<S>(&self, serializer: S) -> Result<S::Ok, S::Error> + where + S: Serializer, + { + match *self { + Bound::Unbounded => serializer.serialize_unit_variant("Bound", 0, "Unbounded"), + Bound::Included(ref value) => { + serializer.serialize_newtype_variant("Bound", 1, "Included", value) + } + Bound::Excluded(ref value) => { + serializer.serialize_newtype_variant("Bound", 2, "Excluded", value) + } + } + } +} + +//////////////////////////////////////////////////////////////////////////////// + +impl Serialize for () { + #[inline] + fn serialize<S>(&self, serializer: S) -> Result<S::Ok, S::Error> + where + S: Serializer, + { + serializer.serialize_unit() + } +} + +#[cfg(feature = "unstable")] +impl Serialize for ! { + fn serialize<S>(&self, _serializer: S) -> Result<S::Ok, S::Error> + where + S: Serializer, + { + *self + } +} + +//////////////////////////////////////////////////////////////////////////////// + +macro_rules! tuple_impls { + ($($len:expr => ($($n:tt $name:ident)+))+) => { + $( + impl<$($name),+> Serialize for ($($name,)+) + where + $($name: Serialize,)+ + { + #[inline] + fn serialize<S>(&self, serializer: S) -> Result<S::Ok, S::Error> + where + S: Serializer, + { + let mut tuple = try!(serializer.serialize_tuple($len)); + $( + try!(tuple.serialize_element(&self.$n)); + )+ + tuple.end() + } + } + )+ + } +} + +tuple_impls! { + 1 => (0 T0) + 2 => (0 T0 1 T1) + 3 => (0 T0 1 T1 2 T2) + 4 => (0 T0 1 T1 2 T2 3 T3) + 5 => (0 T0 1 T1 2 T2 3 T3 4 T4) + 6 => (0 T0 1 T1 2 T2 3 T3 4 T4 5 T5) + 7 => (0 T0 1 T1 2 T2 3 T3 4 T4 5 T5 6 T6) + 8 => (0 T0 1 T1 2 T2 3 T3 4 T4 5 T5 6 T6 7 T7) + 9 => (0 T0 1 T1 2 T2 3 T3 4 T4 5 T5 6 T6 7 T7 8 T8) + 10 => (0 T0 1 T1 2 T2 3 T3 4 T4 5 T5 6 T6 7 T7 8 T8 9 T9) + 11 => (0 T0 1 T1 2 T2 3 T3 4 T4 5 T5 6 T6 7 T7 8 T8 9 T9 10 T10) + 12 => (0 T0 1 T1 2 T2 3 T3 4 T4 5 T5 6 T6 7 T7 8 T8 9 T9 10 T10 11 T11) + 13 => (0 T0 1 T1 2 T2 3 T3 4 T4 5 T5 6 T6 7 T7 8 T8 9 T9 10 T10 11 T11 12 T12) + 14 => (0 T0 1 T1 2 T2 3 T3 4 T4 5 T5 6 T6 7 T7 8 T8 9 T9 10 T10 11 T11 12 T12 13 T13) + 15 => (0 T0 1 T1 2 T2 3 T3 4 T4 5 T5 6 T6 7 T7 8 T8 9 T9 10 T10 11 T11 12 T12 13 T13 14 T14) + 16 => (0 T0 1 T1 2 T2 3 T3 4 T4 5 T5 6 T6 7 T7 8 T8 9 T9 10 T10 11 T11 12 T12 13 T13 14 T14 15 T15) +} + +//////////////////////////////////////////////////////////////////////////////// + +#[cfg(all(any(feature = "std", feature = "alloc"), not(no_relaxed_trait_bounds)))] +macro_rules! map_impl { + ($ty:ident <K $(: $kbound1:ident $(+ $kbound2:ident)*)*, V $(, $typaram:ident : $bound:ident)*>) => { + impl<K, V $(, $typaram)*> Serialize for $ty<K, V $(, $typaram)*> + where + K: Serialize, + V: Serialize, + { + #[inline] + fn serialize<S>(&self, serializer: S) -> Result<S::Ok, S::Error> + where + S: Serializer, + { + serializer.collect_map(self) + } + } + } +} + +#[cfg(all(any(feature = "std", feature = "alloc"), no_relaxed_trait_bounds))] +macro_rules! map_impl { + ($ty:ident <K $(: $kbound1:ident $(+ $kbound2:ident)*)*, V $(, $typaram:ident : $bound:ident)*>) => { + impl<K, V $(, $typaram)*> Serialize for $ty<K, V $(, $typaram)*> + where + K: Serialize $(+ $kbound1 $(+ $kbound2)*)*, + V: Serialize, + $($typaram: $bound,)* + { + #[inline] + fn serialize<S>(&self, serializer: S) -> Result<S::Ok, S::Error> + where + S: Serializer, + { + serializer.collect_map(self) + } + } + } +} + +#[cfg(any(feature = "std", feature = "alloc"))] +map_impl!(BTreeMap<K: Ord, V>); + +#[cfg(feature = "std")] +map_impl!(HashMap<K: Eq + Hash, V, H: BuildHasher>); + +//////////////////////////////////////////////////////////////////////////////// + +macro_rules! deref_impl { + ( + $(#[doc = $doc:tt])* + <$($desc:tt)+ + ) => { + $(#[doc = $doc])* + impl <$($desc)+ { + #[inline] + fn serialize<S>(&self, serializer: S) -> Result<S::Ok, S::Error> + where + S: Serializer, + { + (**self).serialize(serializer) + } + } + }; +} + +deref_impl!(<'a, T: ?Sized> Serialize for &'a T where T: Serialize); +deref_impl!(<'a, T: ?Sized> Serialize for &'a mut T where T: Serialize); + +#[cfg(any(feature = "std", feature = "alloc"))] +deref_impl!(<T: ?Sized> Serialize for Box<T> where T: Serialize); + +#[cfg(all(feature = "rc", any(feature = "std", feature = "alloc")))] +deref_impl! { + /// This impl requires the [`"rc"`] Cargo feature of Serde. + /// + /// Serializing a data structure containing `Rc` will serialize a copy of + /// the contents of the `Rc` each time the `Rc` is referenced within the + /// data structure. Serialization will not attempt to deduplicate these + /// repeated data. + /// + /// [`"rc"`]: https://serde.rs/feature-flags.html#-features-rc + <T: ?Sized> Serialize for Rc<T> where T: Serialize +} + +#[cfg(all(feature = "rc", any(feature = "std", feature = "alloc")))] +deref_impl! { + /// This impl requires the [`"rc"`] Cargo feature of Serde. + /// + /// Serializing a data structure containing `Arc` will serialize a copy of + /// the contents of the `Arc` each time the `Arc` is referenced within the + /// data structure. Serialization will not attempt to deduplicate these + /// repeated data. + /// + /// [`"rc"`]: https://serde.rs/feature-flags.html#-features-rc + <T: ?Sized> Serialize for Arc<T> where T: Serialize +} + +#[cfg(any(feature = "std", feature = "alloc"))] +deref_impl!(<'a, T: ?Sized> Serialize for Cow<'a, T> where T: Serialize + ToOwned); + +//////////////////////////////////////////////////////////////////////////////// + +/// This impl requires the [`"rc"`] Cargo feature of Serde. +/// +/// [`"rc"`]: https://serde.rs/feature-flags.html#-features-rc +#[cfg(all(feature = "rc", any(feature = "std", feature = "alloc")))] +impl<T: ?Sized> Serialize for RcWeak<T> +where + T: Serialize, +{ + fn serialize<S>(&self, serializer: S) -> Result<S::Ok, S::Error> + where + S: Serializer, + { + self.upgrade().serialize(serializer) + } +} + +/// This impl requires the [`"rc"`] Cargo feature of Serde. +/// +/// [`"rc"`]: https://serde.rs/feature-flags.html#-features-rc +#[cfg(all(feature = "rc", any(feature = "std", feature = "alloc")))] +impl<T: ?Sized> Serialize for ArcWeak<T> +where + T: Serialize, +{ + fn serialize<S>(&self, serializer: S) -> Result<S::Ok, S::Error> + where + S: Serializer, + { + self.upgrade().serialize(serializer) + } +} + +//////////////////////////////////////////////////////////////////////////////// + +macro_rules! nonzero_integers { + ($($T:ident,)+) => { + $( + #[cfg(not(no_num_nonzero))] + impl Serialize for num::$T { + fn serialize<S>(&self, serializer: S) -> Result<S::Ok, S::Error> + where + S: Serializer, + { + self.get().serialize(serializer) + } + } + )+ + } +} + +nonzero_integers! { + NonZeroU8, + NonZeroU16, + NonZeroU32, + NonZeroU64, + NonZeroUsize, +} + +#[cfg(not(no_num_nonzero_signed))] +nonzero_integers! { + NonZeroI8, + NonZeroI16, + NonZeroI32, + NonZeroI64, + NonZeroIsize, +} + +// Currently 128-bit integers do not work on Emscripten targets so we need an +// additional `#[cfg]` +serde_if_integer128! { + nonzero_integers! { + NonZeroU128, + } + + #[cfg(not(no_num_nonzero_signed))] + nonzero_integers! { + NonZeroI128, + } +} + +impl<T> Serialize for Cell<T> +where + T: Serialize + Copy, +{ + fn serialize<S>(&self, serializer: S) -> Result<S::Ok, S::Error> + where + S: Serializer, + { + self.get().serialize(serializer) + } +} + +impl<T: ?Sized> Serialize for RefCell<T> +where + T: Serialize, +{ + fn serialize<S>(&self, serializer: S) -> Result<S::Ok, S::Error> + where + S: Serializer, + { + match self.try_borrow() { + Ok(value) => value.serialize(serializer), + Err(_) => Err(S::Error::custom("already mutably borrowed")), + } + } +} + +#[cfg(feature = "std")] +impl<T: ?Sized> Serialize for Mutex<T> +where + T: Serialize, +{ + fn serialize<S>(&self, serializer: S) -> Result<S::Ok, S::Error> + where + S: Serializer, + { + match self.lock() { + Ok(locked) => locked.serialize(serializer), + Err(_) => Err(S::Error::custom("lock poison error while serializing")), + } + } +} + +#[cfg(feature = "std")] +impl<T: ?Sized> Serialize for RwLock<T> +where + T: Serialize, +{ + fn serialize<S>(&self, serializer: S) -> Result<S::Ok, S::Error> + where + S: Serializer, + { + match self.read() { + Ok(locked) => locked.serialize(serializer), + Err(_) => Err(S::Error::custom("lock poison error while serializing")), + } + } +} + +//////////////////////////////////////////////////////////////////////////////// + +impl<T, E> Serialize for Result<T, E> +where + T: Serialize, + E: Serialize, +{ + fn serialize<S>(&self, serializer: S) -> Result<S::Ok, S::Error> + where + S: Serializer, + { + match *self { + Result::Ok(ref value) => serializer.serialize_newtype_variant("Result", 0, "Ok", value), + Result::Err(ref value) => { + serializer.serialize_newtype_variant("Result", 1, "Err", value) + } + } + } +} + +//////////////////////////////////////////////////////////////////////////////// + +#[cfg(any(feature = "std", not(no_core_duration)))] +impl Serialize for Duration { + fn serialize<S>(&self, serializer: S) -> Result<S::Ok, S::Error> + where + S: Serializer, + { + use super::SerializeStruct; + let mut state = try!(serializer.serialize_struct("Duration", 2)); + try!(state.serialize_field("secs", &self.as_secs())); + try!(state.serialize_field("nanos", &self.subsec_nanos())); + state.end() + } +} + +//////////////////////////////////////////////////////////////////////////////// + +#[cfg(feature = "std")] +impl Serialize for SystemTime { + fn serialize<S>(&self, serializer: S) -> Result<S::Ok, S::Error> + where + S: Serializer, + { + use super::SerializeStruct; + let duration_since_epoch = match self.duration_since(UNIX_EPOCH) { + Ok(duration_since_epoch) => duration_since_epoch, + Err(_) => return Err(S::Error::custom("SystemTime must be later than UNIX_EPOCH")), + }; + let mut state = try!(serializer.serialize_struct("SystemTime", 2)); + try!(state.serialize_field("secs_since_epoch", &duration_since_epoch.as_secs())); + try!(state.serialize_field("nanos_since_epoch", &duration_since_epoch.subsec_nanos())); + state.end() + } +} + +//////////////////////////////////////////////////////////////////////////////// + +/// Serialize a value that implements `Display` as a string, when that string is +/// statically known to never have more than a constant `MAX_LEN` bytes. +/// +/// Panics if the `Display` impl tries to write more than `MAX_LEN` bytes. +#[cfg(feature = "std")] +macro_rules! serialize_display_bounded_length { + ($value:expr, $max:expr, $serializer:expr) => {{ + let mut buffer = [0u8; $max]; + let remaining_len = { + let mut remaining = &mut buffer[..]; + write!(remaining, "{}", $value).unwrap(); + remaining.len() + }; + let written_len = buffer.len() - remaining_len; + let written = &buffer[..written_len]; + + // write! only provides fmt::Formatter to Display implementations, which + // has methods write_str and write_char but no method to write arbitrary + // bytes. Therefore `written` must be valid UTF-8. + let written_str = str::from_utf8(written).expect("must be valid UTF-8"); + $serializer.serialize_str(written_str) + }}; +} + +#[cfg(feature = "std")] +impl Serialize for net::IpAddr { + fn serialize<S>(&self, serializer: S) -> Result<S::Ok, S::Error> + where + S: Serializer, + { + if serializer.is_human_readable() { + match *self { + net::IpAddr::V4(ref a) => a.serialize(serializer), + net::IpAddr::V6(ref a) => a.serialize(serializer), + } + } else { + match *self { + net::IpAddr::V4(ref a) => { + serializer.serialize_newtype_variant("IpAddr", 0, "V4", a) + } + net::IpAddr::V6(ref a) => { + serializer.serialize_newtype_variant("IpAddr", 1, "V6", a) + } + } + } + } +} + +#[cfg(feature = "std")] +const DEC_DIGITS_LUT: &'static [u8] = b"\ + 0001020304050607080910111213141516171819\ + 2021222324252627282930313233343536373839\ + 4041424344454647484950515253545556575859\ + 6061626364656667686970717273747576777879\ + 8081828384858687888990919293949596979899"; + +#[cfg(feature = "std")] +#[inline] +fn format_u8(mut n: u8, out: &mut [u8]) -> usize { + if n >= 100 { + let d1 = ((n % 100) << 1) as usize; + n /= 100; + out[0] = b'0' + n; + out[1] = DEC_DIGITS_LUT[d1]; + out[2] = DEC_DIGITS_LUT[d1 + 1]; + 3 + } else if n >= 10 { + let d1 = (n << 1) as usize; + out[0] = DEC_DIGITS_LUT[d1]; + out[1] = DEC_DIGITS_LUT[d1 + 1]; + 2 + } else { + out[0] = b'0' + n; + 1 + } +} + +#[cfg(feature = "std")] +#[test] +fn test_format_u8() { + let mut i = 0u8; + + loop { + let mut buf = [0u8; 3]; + let written = format_u8(i, &mut buf); + assert_eq!(i.to_string().as_bytes(), &buf[..written]); + + match i.checked_add(1) { + Some(next) => i = next, + None => break, + } + } +} + +#[cfg(feature = "std")] +impl Serialize for net::Ipv4Addr { + fn serialize<S>(&self, serializer: S) -> Result<S::Ok, S::Error> + where + S: Serializer, + { + if serializer.is_human_readable() { + const MAX_LEN: usize = 15; + debug_assert_eq!(MAX_LEN, "101.102.103.104".len()); + let mut buf = [b'.'; MAX_LEN]; + let mut written = format_u8(self.octets()[0], &mut buf); + for oct in &self.octets()[1..] { + // Skip over delimiters that we initialized buf with + written += format_u8(*oct, &mut buf[written + 1..]) + 1; + } + // Safety: We've only written ASCII bytes to the buffer, so it is valid UTF-8 + let buf = unsafe { str::from_utf8_unchecked(&buf[..written]) }; + serializer.serialize_str(buf) + } else { + self.octets().serialize(serializer) + } + } +} + +#[cfg(feature = "std")] +impl Serialize for net::Ipv6Addr { + fn serialize<S>(&self, serializer: S) -> Result<S::Ok, S::Error> + where + S: Serializer, + { + if serializer.is_human_readable() { + const MAX_LEN: usize = 39; + debug_assert_eq!(MAX_LEN, "1001:1002:1003:1004:1005:1006:1007:1008".len()); + serialize_display_bounded_length!(self, MAX_LEN, serializer) + } else { + self.octets().serialize(serializer) + } + } +} + +#[cfg(feature = "std")] +impl Serialize for net::SocketAddr { + fn serialize<S>(&self, serializer: S) -> Result<S::Ok, S::Error> + where + S: Serializer, + { + if serializer.is_human_readable() { + match *self { + net::SocketAddr::V4(ref addr) => addr.serialize(serializer), + net::SocketAddr::V6(ref addr) => addr.serialize(serializer), + } + } else { + match *self { + net::SocketAddr::V4(ref addr) => { + serializer.serialize_newtype_variant("SocketAddr", 0, "V4", addr) + } + net::SocketAddr::V6(ref addr) => { + serializer.serialize_newtype_variant("SocketAddr", 1, "V6", addr) + } + } + } + } +} + +#[cfg(feature = "std")] +impl Serialize for net::SocketAddrV4 { + fn serialize<S>(&self, serializer: S) -> Result<S::Ok, S::Error> + where + S: Serializer, + { + if serializer.is_human_readable() { + const MAX_LEN: usize = 21; + debug_assert_eq!(MAX_LEN, "101.102.103.104:65000".len()); + serialize_display_bounded_length!(self, MAX_LEN, serializer) + } else { + (self.ip(), self.port()).serialize(serializer) + } + } +} + +#[cfg(feature = "std")] +impl Serialize for net::SocketAddrV6 { + fn serialize<S>(&self, serializer: S) -> Result<S::Ok, S::Error> + where + S: Serializer, + { + if serializer.is_human_readable() { + const MAX_LEN: usize = 58; + debug_assert_eq!( + MAX_LEN, + "[1001:1002:1003:1004:1005:1006:1007:1008%4294967295]:65000".len() + ); + serialize_display_bounded_length!(self, MAX_LEN, serializer) + } else { + (self.ip(), self.port()).serialize(serializer) + } + } +} + +//////////////////////////////////////////////////////////////////////////////// + +#[cfg(feature = "std")] +impl Serialize for Path { + fn serialize<S>(&self, serializer: S) -> Result<S::Ok, S::Error> + where + S: Serializer, + { + match self.to_str() { + Some(s) => s.serialize(serializer), + None => Err(Error::custom("path contains invalid UTF-8 characters")), + } + } +} + +#[cfg(feature = "std")] +impl Serialize for PathBuf { + fn serialize<S>(&self, serializer: S) -> Result<S::Ok, S::Error> + where + S: Serializer, + { + self.as_path().serialize(serializer) + } +} + +#[cfg(all(feature = "std", any(unix, windows)))] +impl Serialize for OsStr { + #[cfg(unix)] + fn serialize<S>(&self, serializer: S) -> Result<S::Ok, S::Error> + where + S: Serializer, + { + use std::os::unix::ffi::OsStrExt; + serializer.serialize_newtype_variant("OsString", 0, "Unix", self.as_bytes()) + } + + #[cfg(windows)] + fn serialize<S>(&self, serializer: S) -> Result<S::Ok, S::Error> + where + S: Serializer, + { + use std::os::windows::ffi::OsStrExt; + let val = self.encode_wide().collect::<Vec<_>>(); + serializer.serialize_newtype_variant("OsString", 1, "Windows", &val) + } +} + +#[cfg(all(feature = "std", any(unix, windows)))] +impl Serialize for OsString { + fn serialize<S>(&self, serializer: S) -> Result<S::Ok, S::Error> + where + S: Serializer, + { + self.as_os_str().serialize(serializer) + } +} + +//////////////////////////////////////////////////////////////////////////////// + +impl<T> Serialize for Wrapping<T> +where + T: Serialize, +{ + #[inline] + fn serialize<S>(&self, serializer: S) -> Result<S::Ok, S::Error> + where + S: Serializer, + { + self.0.serialize(serializer) + } +} + +#[cfg(not(no_core_reverse))] +impl<T> Serialize for Reverse<T> +where + T: Serialize, +{ + #[inline] + fn serialize<S>(&self, serializer: S) -> Result<S::Ok, S::Error> + where + S: Serializer, + { + self.0.serialize(serializer) + } +} + +//////////////////////////////////////////////////////////////////////////////// + +#[cfg(all(feature = "std", not(no_std_atomic)))] +macro_rules! atomic_impl { + ($($ty:ident $size:expr)*) => { + $( + #[cfg(any(no_target_has_atomic, target_has_atomic = $size))] + impl Serialize for $ty { + fn serialize<S>(&self, serializer: S) -> Result<S::Ok, S::Error> + where + S: Serializer, + { + // Matches the atomic ordering used in libcore for the Debug impl + self.load(Ordering::Relaxed).serialize(serializer) + } + } + )* + } +} + +#[cfg(all(feature = "std", not(no_std_atomic)))] +atomic_impl! { + AtomicBool "8" + AtomicI8 "8" + AtomicI16 "16" + AtomicI32 "32" + AtomicIsize "ptr" + AtomicU8 "8" + AtomicU16 "16" + AtomicU32 "32" + AtomicUsize "ptr" +} + +#[cfg(all(feature = "std", not(no_std_atomic64)))] +atomic_impl! { + AtomicI64 "64" + AtomicU64 "64" +} diff --git a/src/ser/impossible.rs b/src/ser/impossible.rs new file mode 100644 index 0000000..e8df9ca --- /dev/null +++ b/src/ser/impossible.rs @@ -0,0 +1,216 @@ +//! This module contains `Impossible` serializer and its implementations. + +use lib::*; + +use ser::{ + self, Serialize, SerializeMap, SerializeSeq, SerializeStruct, SerializeStructVariant, + SerializeTuple, SerializeTupleStruct, SerializeTupleVariant, +}; + +/// Helper type for implementing a `Serializer` that does not support +/// serializing one of the compound types. +/// +/// This type cannot be instantiated, but implements every one of the traits +/// corresponding to the [`Serializer`] compound types: [`SerializeSeq`], +/// [`SerializeTuple`], [`SerializeTupleStruct`], [`SerializeTupleVariant`], +/// [`SerializeMap`], [`SerializeStruct`], and [`SerializeStructVariant`]. +/// +/// ```edition2018 +/// # use serde::ser::{Serializer, Impossible}; +/// # use serde::__private::doc::Error; +/// # +/// # struct MySerializer; +/// # +/// impl Serializer for MySerializer { +/// type Ok = (); +/// type Error = Error; +/// +/// type SerializeSeq = Impossible<(), Error>; +/// /* other associated types */ +/// +/// /// This data format does not support serializing sequences. +/// fn serialize_seq(self, +/// len: Option<usize>) +/// -> Result<Self::SerializeSeq, Error> { +/// // Given Impossible cannot be instantiated, the only +/// // thing we can do here is to return an error. +/// # stringify! { +/// Err(...) +/// # }; +/// # unimplemented!() +/// } +/// +/// /* other Serializer methods */ +/// # serde::__serialize_unimplemented! { +/// # bool i8 i16 i32 i64 u8 u16 u32 u64 f32 f64 char str bytes none some +/// # unit unit_struct unit_variant newtype_struct newtype_variant +/// # tuple tuple_struct tuple_variant map struct struct_variant +/// # } +/// } +/// ``` +/// +/// [`Serializer`]: trait.Serializer.html +/// [`SerializeSeq`]: trait.SerializeSeq.html +/// [`SerializeTuple`]: trait.SerializeTuple.html +/// [`SerializeTupleStruct`]: trait.SerializeTupleStruct.html +/// [`SerializeTupleVariant`]: trait.SerializeTupleVariant.html +/// [`SerializeMap`]: trait.SerializeMap.html +/// [`SerializeStruct`]: trait.SerializeStruct.html +/// [`SerializeStructVariant`]: trait.SerializeStructVariant.html +pub struct Impossible<Ok, Error> { + void: Void, + ok: PhantomData<Ok>, + error: PhantomData<Error>, +} + +enum Void {} + +impl<Ok, Error> SerializeSeq for Impossible<Ok, Error> +where + Error: ser::Error, +{ + type Ok = Ok; + type Error = Error; + + fn serialize_element<T: ?Sized>(&mut self, value: &T) -> Result<(), Error> + where + T: Serialize, + { + let _ = value; + match self.void {} + } + + fn end(self) -> Result<Ok, Error> { + match self.void {} + } +} + +impl<Ok, Error> SerializeTuple for Impossible<Ok, Error> +where + Error: ser::Error, +{ + type Ok = Ok; + type Error = Error; + + fn serialize_element<T: ?Sized>(&mut self, value: &T) -> Result<(), Error> + where + T: Serialize, + { + let _ = value; + match self.void {} + } + + fn end(self) -> Result<Ok, Error> { + match self.void {} + } +} + +impl<Ok, Error> SerializeTupleStruct for Impossible<Ok, Error> +where + Error: ser::Error, +{ + type Ok = Ok; + type Error = Error; + + fn serialize_field<T: ?Sized>(&mut self, value: &T) -> Result<(), Error> + where + T: Serialize, + { + let _ = value; + match self.void {} + } + + fn end(self) -> Result<Ok, Error> { + match self.void {} + } +} + +impl<Ok, Error> SerializeTupleVariant for Impossible<Ok, Error> +where + Error: ser::Error, +{ + type Ok = Ok; + type Error = Error; + + fn serialize_field<T: ?Sized>(&mut self, value: &T) -> Result<(), Error> + where + T: Serialize, + { + let _ = value; + match self.void {} + } + + fn end(self) -> Result<Ok, Error> { + match self.void {} + } +} + +impl<Ok, Error> SerializeMap for Impossible<Ok, Error> +where + Error: ser::Error, +{ + type Ok = Ok; + type Error = Error; + + fn serialize_key<T: ?Sized>(&mut self, key: &T) -> Result<(), Error> + where + T: Serialize, + { + let _ = key; + match self.void {} + } + + fn serialize_value<T: ?Sized>(&mut self, value: &T) -> Result<(), Error> + where + T: Serialize, + { + let _ = value; + match self.void {} + } + + fn end(self) -> Result<Ok, Error> { + match self.void {} + } +} + +impl<Ok, Error> SerializeStruct for Impossible<Ok, Error> +where + Error: ser::Error, +{ + type Ok = Ok; + type Error = Error; + + fn serialize_field<T: ?Sized>(&mut self, key: &'static str, value: &T) -> Result<(), Error> + where + T: Serialize, + { + let _ = key; + let _ = value; + match self.void {} + } + + fn end(self) -> Result<Ok, Error> { + match self.void {} + } +} + +impl<Ok, Error> SerializeStructVariant for Impossible<Ok, Error> +where + Error: ser::Error, +{ + type Ok = Ok; + type Error = Error; + + fn serialize_field<T: ?Sized>(&mut self, key: &'static str, value: &T) -> Result<(), Error> + where + T: Serialize, + { + let _ = key; + let _ = value; + match self.void {} + } + + fn end(self) -> Result<Ok, Error> { + match self.void {} + } +} diff --git a/src/ser/mod.rs b/src/ser/mod.rs new file mode 100644 index 0000000..5c45426 --- /dev/null +++ b/src/ser/mod.rs @@ -0,0 +1,1988 @@ +//! Generic data structure serialization framework. +//! +//! The two most important traits in this module are [`Serialize`] and +//! [`Serializer`]. +//! +//! - **A type that implements `Serialize` is a data structure** that can be +//! serialized to any data format supported by Serde, and conversely +//! - **A type that implements `Serializer` is a data format** that can +//! serialize any data structure supported by Serde. +//! +//! # The Serialize trait +//! +//! Serde provides [`Serialize`] implementations for many Rust primitive and +//! standard library types. The complete list is below. All of these can be +//! serialized using Serde out of the box. +//! +//! Additionally, Serde provides a procedural macro called [`serde_derive`] to +//! automatically generate [`Serialize`] implementations for structs and enums +//! in your program. See the [derive section of the manual] for how to use this. +//! +//! In rare cases it may be necessary to implement [`Serialize`] manually for +//! some type in your program. See the [Implementing `Serialize`] section of the +//! manual for more about this. +//! +//! Third-party crates may provide [`Serialize`] implementations for types that +//! they expose. For example the [`linked-hash-map`] crate provides a +//! [`LinkedHashMap<K, V>`] type that is serializable by Serde because the crate +//! provides an implementation of [`Serialize`] for it. +//! +//! # The Serializer trait +//! +//! [`Serializer`] implementations are provided by third-party crates, for +//! example [`serde_json`], [`serde_yaml`] and [`postcard`]. +//! +//! A partial list of well-maintained formats is given on the [Serde +//! website][data formats]. +//! +//! # Implementations of Serialize provided by Serde +//! +//! - **Primitive types**: +//! - bool +//! - i8, i16, i32, i64, i128, isize +//! - u8, u16, u32, u64, u128, usize +//! - f32, f64 +//! - char +//! - str +//! - &T and &mut T +//! - **Compound types**: +//! - \[T\] +//! - \[T; 0\] through \[T; 32\] +//! - tuples up to size 16 +//! - **Common standard library types**: +//! - String +//! - Option\<T\> +//! - Result\<T, E\> +//! - PhantomData\<T\> +//! - **Wrapper types**: +//! - Box\<T\> +//! - Cow\<'a, T\> +//! - Cell\<T\> +//! - RefCell\<T\> +//! - Mutex\<T\> +//! - RwLock\<T\> +//! - Rc\<T\> *(if* features = ["rc"] *is enabled)* +//! - Arc\<T\> *(if* features = ["rc"] *is enabled)* +//! - **Collection types**: +//! - BTreeMap\<K, V\> +//! - BTreeSet\<T\> +//! - BinaryHeap\<T\> +//! - HashMap\<K, V, H\> +//! - HashSet\<T, H\> +//! - LinkedList\<T\> +//! - VecDeque\<T\> +//! - Vec\<T\> +//! - **FFI types**: +//! - CStr +//! - CString +//! - OsStr +//! - OsString +//! - **Miscellaneous standard library types**: +//! - Duration +//! - SystemTime +//! - Path +//! - PathBuf +//! - Range\<T\> +//! - RangeInclusive\<T\> +//! - Bound\<T\> +//! - num::NonZero* +//! - `!` *(unstable)* +//! - **Net types**: +//! - IpAddr +//! - Ipv4Addr +//! - Ipv6Addr +//! - SocketAddr +//! - SocketAddrV4 +//! - SocketAddrV6 +//! +//! [Implementing `Serialize`]: https://serde.rs/impl-serialize.html +//! [`LinkedHashMap<K, V>`]: https://docs.rs/linked-hash-map/*/linked_hash_map/struct.LinkedHashMap.html +//! [`Serialize`]: ../trait.Serialize.html +//! [`Serializer`]: ../trait.Serializer.html +//! [`postcard`]: https://github.com/jamesmunns/postcard +//! [`linked-hash-map`]: https://crates.io/crates/linked-hash-map +//! [`serde_derive`]: https://crates.io/crates/serde_derive +//! [`serde_json`]: https://github.com/serde-rs/json +//! [`serde_yaml`]: https://github.com/dtolnay/serde-yaml +//! [derive section of the manual]: https://serde.rs/derive.html +//! [data formats]: https://serde.rs/#data-formats + +use lib::*; + +mod fmt; +mod impls; +mod impossible; + +pub use self::impossible::Impossible; + +#[cfg(all(feature = "unstable", not(feature = "std")))] +#[doc(inline)] +pub use core::error::Error as StdError; +#[cfg(feature = "std")] +#[doc(no_inline)] +pub use std::error::Error as StdError; +#[cfg(not(any(feature = "std", feature = "unstable")))] +#[doc(no_inline)] +pub use std_error::Error as StdError; + +//////////////////////////////////////////////////////////////////////////////// + +macro_rules! declare_error_trait { + (Error: Sized $(+ $($supertrait:ident)::+)*) => { + /// Trait used by `Serialize` implementations to generically construct + /// errors belonging to the `Serializer` against which they are + /// currently running. + /// + /// # Example implementation + /// + /// The [example data format] presented on the website shows an error + /// type appropriate for a basic JSON data format. + /// + /// [example data format]: https://serde.rs/data-format.html + pub trait Error: Sized $(+ $($supertrait)::+)* { + /// Used when a [`Serialize`] implementation encounters any error + /// while serializing a type. + /// + /// The message should not be capitalized and should not end with a + /// period. + /// + /// For example, a filesystem [`Path`] may refuse to serialize + /// itself if it contains invalid UTF-8 data. + /// + /// ```edition2018 + /// # struct Path; + /// # + /// # impl Path { + /// # fn to_str(&self) -> Option<&str> { + /// # unimplemented!() + /// # } + /// # } + /// # + /// use serde::ser::{self, Serialize, Serializer}; + /// + /// impl Serialize for Path { + /// fn serialize<S>(&self, serializer: S) -> Result<S::Ok, S::Error> + /// where + /// S: Serializer, + /// { + /// match self.to_str() { + /// Some(s) => serializer.serialize_str(s), + /// None => Err(ser::Error::custom("path contains invalid UTF-8 characters")), + /// } + /// } + /// } + /// ``` + /// + /// [`Path`]: https://doc.rust-lang.org/std/path/struct.Path.html + /// [`Serialize`]: ../trait.Serialize.html + fn custom<T>(msg: T) -> Self + where + T: Display; + } + } +} + +#[cfg(feature = "std")] +declare_error_trait!(Error: Sized + StdError); + +#[cfg(not(feature = "std"))] +declare_error_trait!(Error: Sized + Debug + Display); + +//////////////////////////////////////////////////////////////////////////////// + +/// A **data structure** that can be serialized into any data format supported +/// by Serde. +/// +/// Serde provides `Serialize` implementations for many Rust primitive and +/// standard library types. The complete list is [here][crate::ser]. All of +/// these can be serialized using Serde out of the box. +/// +/// Additionally, Serde provides a procedural macro called [`serde_derive`] to +/// automatically generate `Serialize` implementations for structs and enums in +/// your program. See the [derive section of the manual] for how to use this. +/// +/// In rare cases it may be necessary to implement `Serialize` manually for some +/// type in your program. See the [Implementing `Serialize`] section of the +/// manual for more about this. +/// +/// Third-party crates may provide `Serialize` implementations for types that +/// they expose. For example the [`linked-hash-map`] crate provides a +/// [`LinkedHashMap<K, V>`] type that is serializable by Serde because the crate +/// provides an implementation of `Serialize` for it. +/// +/// [Implementing `Serialize`]: https://serde.rs/impl-serialize.html +/// [`LinkedHashMap<K, V>`]: https://docs.rs/linked-hash-map/*/linked_hash_map/struct.LinkedHashMap.html +/// [`linked-hash-map`]: https://crates.io/crates/linked-hash-map +/// [`serde_derive`]: https://crates.io/crates/serde_derive +/// [derive section of the manual]: https://serde.rs/derive.html +pub trait Serialize { + /// Serialize this value into the given Serde serializer. + /// + /// See the [Implementing `Serialize`] section of the manual for more + /// information about how to implement this method. + /// + /// ```edition2018 + /// use serde::ser::{Serialize, SerializeStruct, Serializer}; + /// + /// struct Person { + /// name: String, + /// age: u8, + /// phones: Vec<String>, + /// } + /// + /// // This is what #[derive(Serialize)] would generate. + /// impl Serialize for Person { + /// fn serialize<S>(&self, serializer: S) -> Result<S::Ok, S::Error> + /// where + /// S: Serializer, + /// { + /// let mut s = serializer.serialize_struct("Person", 3)?; + /// s.serialize_field("name", &self.name)?; + /// s.serialize_field("age", &self.age)?; + /// s.serialize_field("phones", &self.phones)?; + /// s.end() + /// } + /// } + /// ``` + /// + /// [Implementing `Serialize`]: https://serde.rs/impl-serialize.html + fn serialize<S>(&self, serializer: S) -> Result<S::Ok, S::Error> + where + S: Serializer; +} + +//////////////////////////////////////////////////////////////////////////////// + +/// A **data format** that can serialize any data structure supported by Serde. +/// +/// The role of this trait is to define the serialization half of the [Serde +/// data model], which is a way to categorize every Rust data structure into one +/// of 29 possible types. Each method of the `Serializer` trait corresponds to +/// one of the types of the data model. +/// +/// Implementations of `Serialize` map themselves into this data model by +/// invoking exactly one of the `Serializer` methods. +/// +/// The types that make up the Serde data model are: +/// +/// - **14 primitive types** +/// - bool +/// - i8, i16, i32, i64, i128 +/// - u8, u16, u32, u64, u128 +/// - f32, f64 +/// - char +/// - **string** +/// - UTF-8 bytes with a length and no null terminator. +/// - When serializing, all strings are handled equally. When deserializing, +/// there are three flavors of strings: transient, owned, and borrowed. +/// - **byte array** - \[u8\] +/// - Similar to strings, during deserialization byte arrays can be +/// transient, owned, or borrowed. +/// - **option** +/// - Either none or some value. +/// - **unit** +/// - The type of `()` in Rust. It represents an anonymous value containing +/// no data. +/// - **unit_struct** +/// - For example `struct Unit` or `PhantomData<T>`. It represents a named +/// value containing no data. +/// - **unit_variant** +/// - For example the `E::A` and `E::B` in `enum E { A, B }`. +/// - **newtype_struct** +/// - For example `struct Millimeters(u8)`. +/// - **newtype_variant** +/// - For example the `E::N` in `enum E { N(u8) }`. +/// - **seq** +/// - A variably sized heterogeneous sequence of values, for example +/// `Vec<T>` or `HashSet<T>`. When serializing, the length may or may not +/// be known before iterating through all the data. When deserializing, +/// the length is determined by looking at the serialized data. +/// - **tuple** +/// - A statically sized heterogeneous sequence of values for which the +/// length will be known at deserialization time without looking at the +/// serialized data, for example `(u8,)` or `(String, u64, Vec<T>)` or +/// `[u64; 10]`. +/// - **tuple_struct** +/// - A named tuple, for example `struct Rgb(u8, u8, u8)`. +/// - **tuple_variant** +/// - For example the `E::T` in `enum E { T(u8, u8) }`. +/// - **map** +/// - A heterogeneous key-value pairing, for example `BTreeMap<K, V>`. +/// - **struct** +/// - A heterogeneous key-value pairing in which the keys are strings and +/// will be known at deserialization time without looking at the +/// serialized data, for example `struct S { r: u8, g: u8, b: u8 }`. +/// - **struct_variant** +/// - For example the `E::S` in `enum E { S { r: u8, g: u8, b: u8 } }`. +/// +/// Many Serde serializers produce text or binary data as output, for example +/// JSON or Postcard. This is not a requirement of the `Serializer` trait, and +/// there are serializers that do not produce text or binary output. One example +/// is the `serde_json::value::Serializer` (distinct from the main `serde_json` +/// serializer) that produces a `serde_json::Value` data structure in memory as +/// output. +/// +/// [Serde data model]: https://serde.rs/data-model.html +/// +/// # Example implementation +/// +/// The [example data format] presented on the website contains example code for +/// a basic JSON `Serializer`. +/// +/// [example data format]: https://serde.rs/data-format.html +pub trait Serializer: Sized { + /// The output type produced by this `Serializer` during successful + /// serialization. Most serializers that produce text or binary output + /// should set `Ok = ()` and serialize into an [`io::Write`] or buffer + /// contained within the `Serializer` instance. Serializers that build + /// in-memory data structures may be simplified by using `Ok` to propagate + /// the data structure around. + /// + /// [`io::Write`]: https://doc.rust-lang.org/std/io/trait.Write.html + type Ok; + + /// The error type when some error occurs during serialization. + type Error: Error; + + /// Type returned from [`serialize_seq`] for serializing the content of the + /// sequence. + /// + /// [`serialize_seq`]: #tymethod.serialize_seq + type SerializeSeq: SerializeSeq<Ok = Self::Ok, Error = Self::Error>; + + /// Type returned from [`serialize_tuple`] for serializing the content of + /// the tuple. + /// + /// [`serialize_tuple`]: #tymethod.serialize_tuple + type SerializeTuple: SerializeTuple<Ok = Self::Ok, Error = Self::Error>; + + /// Type returned from [`serialize_tuple_struct`] for serializing the + /// content of the tuple struct. + /// + /// [`serialize_tuple_struct`]: #tymethod.serialize_tuple_struct + type SerializeTupleStruct: SerializeTupleStruct<Ok = Self::Ok, Error = Self::Error>; + + /// Type returned from [`serialize_tuple_variant`] for serializing the + /// content of the tuple variant. + /// + /// [`serialize_tuple_variant`]: #tymethod.serialize_tuple_variant + type SerializeTupleVariant: SerializeTupleVariant<Ok = Self::Ok, Error = Self::Error>; + + /// Type returned from [`serialize_map`] for serializing the content of the + /// map. + /// + /// [`serialize_map`]: #tymethod.serialize_map + type SerializeMap: SerializeMap<Ok = Self::Ok, Error = Self::Error>; + + /// Type returned from [`serialize_struct`] for serializing the content of + /// the struct. + /// + /// [`serialize_struct`]: #tymethod.serialize_struct + type SerializeStruct: SerializeStruct<Ok = Self::Ok, Error = Self::Error>; + + /// Type returned from [`serialize_struct_variant`] for serializing the + /// content of the struct variant. + /// + /// [`serialize_struct_variant`]: #tymethod.serialize_struct_variant + type SerializeStructVariant: SerializeStructVariant<Ok = Self::Ok, Error = Self::Error>; + + /// Serialize a `bool` value. + /// + /// ```edition2018 + /// # use serde::Serializer; + /// # + /// # serde::__private_serialize!(); + /// # + /// impl Serialize for bool { + /// fn serialize<S>(&self, serializer: S) -> Result<S::Ok, S::Error> + /// where + /// S: Serializer, + /// { + /// serializer.serialize_bool(*self) + /// } + /// } + /// ``` + fn serialize_bool(self, v: bool) -> Result<Self::Ok, Self::Error>; + + /// Serialize an `i8` value. + /// + /// If the format does not differentiate between `i8` and `i64`, a + /// reasonable implementation would be to cast the value to `i64` and + /// forward to `serialize_i64`. + /// + /// ```edition2018 + /// # use serde::Serializer; + /// # + /// # serde::__private_serialize!(); + /// # + /// impl Serialize for i8 { + /// fn serialize<S>(&self, serializer: S) -> Result<S::Ok, S::Error> + /// where + /// S: Serializer, + /// { + /// serializer.serialize_i8(*self) + /// } + /// } + /// ``` + fn serialize_i8(self, v: i8) -> Result<Self::Ok, Self::Error>; + + /// Serialize an `i16` value. + /// + /// If the format does not differentiate between `i16` and `i64`, a + /// reasonable implementation would be to cast the value to `i64` and + /// forward to `serialize_i64`. + /// + /// ```edition2018 + /// # use serde::Serializer; + /// # + /// # serde::__private_serialize!(); + /// # + /// impl Serialize for i16 { + /// fn serialize<S>(&self, serializer: S) -> Result<S::Ok, S::Error> + /// where + /// S: Serializer, + /// { + /// serializer.serialize_i16(*self) + /// } + /// } + /// ``` + fn serialize_i16(self, v: i16) -> Result<Self::Ok, Self::Error>; + + /// Serialize an `i32` value. + /// + /// If the format does not differentiate between `i32` and `i64`, a + /// reasonable implementation would be to cast the value to `i64` and + /// forward to `serialize_i64`. + /// + /// ```edition2018 + /// # use serde::Serializer; + /// # + /// # serde::__private_serialize!(); + /// # + /// impl Serialize for i32 { + /// fn serialize<S>(&self, serializer: S) -> Result<S::Ok, S::Error> + /// where + /// S: Serializer, + /// { + /// serializer.serialize_i32(*self) + /// } + /// } + /// ``` + fn serialize_i32(self, v: i32) -> Result<Self::Ok, Self::Error>; + + /// Serialize an `i64` value. + /// + /// ```edition2018 + /// # use serde::Serializer; + /// # + /// # serde::__private_serialize!(); + /// # + /// impl Serialize for i64 { + /// fn serialize<S>(&self, serializer: S) -> Result<S::Ok, S::Error> + /// where + /// S: Serializer, + /// { + /// serializer.serialize_i64(*self) + /// } + /// } + /// ``` + fn serialize_i64(self, v: i64) -> Result<Self::Ok, Self::Error>; + + serde_if_integer128! { + /// Serialize an `i128` value. + /// + /// ```edition2018 + /// # use serde::Serializer; + /// # + /// # serde::__private_serialize!(); + /// # + /// impl Serialize for i128 { + /// fn serialize<S>(&self, serializer: S) -> Result<S::Ok, S::Error> + /// where + /// S: Serializer, + /// { + /// serializer.serialize_i128(*self) + /// } + /// } + /// ``` + /// + /// This method is available only on Rust compiler versions >=1.26. The + /// default behavior unconditionally returns an error. + fn serialize_i128(self, v: i128) -> Result<Self::Ok, Self::Error> { + let _ = v; + Err(Error::custom("i128 is not supported")) + } + } + + /// Serialize a `u8` value. + /// + /// If the format does not differentiate between `u8` and `u64`, a + /// reasonable implementation would be to cast the value to `u64` and + /// forward to `serialize_u64`. + /// + /// ```edition2018 + /// # use serde::Serializer; + /// # + /// # serde::__private_serialize!(); + /// # + /// impl Serialize for u8 { + /// fn serialize<S>(&self, serializer: S) -> Result<S::Ok, S::Error> + /// where + /// S: Serializer, + /// { + /// serializer.serialize_u8(*self) + /// } + /// } + /// ``` + fn serialize_u8(self, v: u8) -> Result<Self::Ok, Self::Error>; + + /// Serialize a `u16` value. + /// + /// If the format does not differentiate between `u16` and `u64`, a + /// reasonable implementation would be to cast the value to `u64` and + /// forward to `serialize_u64`. + /// + /// ```edition2018 + /// # use serde::Serializer; + /// # + /// # serde::__private_serialize!(); + /// # + /// impl Serialize for u16 { + /// fn serialize<S>(&self, serializer: S) -> Result<S::Ok, S::Error> + /// where + /// S: Serializer, + /// { + /// serializer.serialize_u16(*self) + /// } + /// } + /// ``` + fn serialize_u16(self, v: u16) -> Result<Self::Ok, Self::Error>; + + /// Serialize a `u32` value. + /// + /// If the format does not differentiate between `u32` and `u64`, a + /// reasonable implementation would be to cast the value to `u64` and + /// forward to `serialize_u64`. + /// + /// ```edition2018 + /// # use serde::Serializer; + /// # + /// # serde::__private_serialize!(); + /// # + /// impl Serialize for u32 { + /// fn serialize<S>(&self, serializer: S) -> Result<S::Ok, S::Error> + /// where + /// S: Serializer, + /// { + /// serializer.serialize_u32(*self) + /// } + /// } + /// ``` + fn serialize_u32(self, v: u32) -> Result<Self::Ok, Self::Error>; + + /// Serialize a `u64` value. + /// + /// ```edition2018 + /// # use serde::Serializer; + /// # + /// # serde::__private_serialize!(); + /// # + /// impl Serialize for u64 { + /// fn serialize<S>(&self, serializer: S) -> Result<S::Ok, S::Error> + /// where + /// S: Serializer, + /// { + /// serializer.serialize_u64(*self) + /// } + /// } + /// ``` + fn serialize_u64(self, v: u64) -> Result<Self::Ok, Self::Error>; + + serde_if_integer128! { + /// Serialize a `u128` value. + /// + /// ```edition2018 + /// # use serde::Serializer; + /// # + /// # serde::__private_serialize!(); + /// # + /// impl Serialize for u128 { + /// fn serialize<S>(&self, serializer: S) -> Result<S::Ok, S::Error> + /// where + /// S: Serializer, + /// { + /// serializer.serialize_u128(*self) + /// } + /// } + /// ``` + /// + /// This method is available only on Rust compiler versions >=1.26. The + /// default behavior unconditionally returns an error. + fn serialize_u128(self, v: u128) -> Result<Self::Ok, Self::Error> { + let _ = v; + Err(Error::custom("u128 is not supported")) + } + } + + /// Serialize an `f32` value. + /// + /// If the format does not differentiate between `f32` and `f64`, a + /// reasonable implementation would be to cast the value to `f64` and + /// forward to `serialize_f64`. + /// + /// ```edition2018 + /// # use serde::Serializer; + /// # + /// # serde::__private_serialize!(); + /// # + /// impl Serialize for f32 { + /// fn serialize<S>(&self, serializer: S) -> Result<S::Ok, S::Error> + /// where + /// S: Serializer, + /// { + /// serializer.serialize_f32(*self) + /// } + /// } + /// ``` + fn serialize_f32(self, v: f32) -> Result<Self::Ok, Self::Error>; + + /// Serialize an `f64` value. + /// + /// ```edition2018 + /// # use serde::Serializer; + /// # + /// # serde::__private_serialize!(); + /// # + /// impl Serialize for f64 { + /// fn serialize<S>(&self, serializer: S) -> Result<S::Ok, S::Error> + /// where + /// S: Serializer, + /// { + /// serializer.serialize_f64(*self) + /// } + /// } + /// ``` + fn serialize_f64(self, v: f64) -> Result<Self::Ok, Self::Error>; + + /// Serialize a character. + /// + /// If the format does not support characters, it is reasonable to serialize + /// it as a single element `str` or a `u32`. + /// + /// ```edition2018 + /// # use serde::Serializer; + /// # + /// # serde::__private_serialize!(); + /// # + /// impl Serialize for char { + /// fn serialize<S>(&self, serializer: S) -> Result<S::Ok, S::Error> + /// where + /// S: Serializer, + /// { + /// serializer.serialize_char(*self) + /// } + /// } + /// ``` + fn serialize_char(self, v: char) -> Result<Self::Ok, Self::Error>; + + /// Serialize a `&str`. + /// + /// ```edition2018 + /// # use serde::Serializer; + /// # + /// # serde::__private_serialize!(); + /// # + /// impl Serialize for str { + /// fn serialize<S>(&self, serializer: S) -> Result<S::Ok, S::Error> + /// where + /// S: Serializer, + /// { + /// serializer.serialize_str(self) + /// } + /// } + /// ``` + fn serialize_str(self, v: &str) -> Result<Self::Ok, Self::Error>; + + /// Serialize a chunk of raw byte data. + /// + /// Enables serializers to serialize byte slices more compactly or more + /// efficiently than other types of slices. If no efficient implementation + /// is available, a reasonable implementation would be to forward to + /// `serialize_seq`. If forwarded, the implementation looks usually just + /// like this: + /// + /// ```edition2018 + /// # use serde::ser::{Serializer, SerializeSeq}; + /// # use serde::__private::doc::Error; + /// # + /// # struct MySerializer; + /// # + /// # impl Serializer for MySerializer { + /// # type Ok = (); + /// # type Error = Error; + /// # + /// fn serialize_bytes(self, v: &[u8]) -> Result<Self::Ok, Self::Error> { + /// let mut seq = self.serialize_seq(Some(v.len()))?; + /// for b in v { + /// seq.serialize_element(b)?; + /// } + /// seq.end() + /// } + /// # + /// # serde::__serialize_unimplemented! { + /// # bool i8 i16 i32 i64 u8 u16 u32 u64 f32 f64 char str none some + /// # unit unit_struct unit_variant newtype_struct newtype_variant + /// # seq tuple tuple_struct tuple_variant map struct struct_variant + /// # } + /// # } + /// ``` + fn serialize_bytes(self, v: &[u8]) -> Result<Self::Ok, Self::Error>; + + /// Serialize a [`None`] value. + /// + /// ```edition2018 + /// # use serde::{Serialize, Serializer}; + /// # + /// # enum Option<T> { + /// # Some(T), + /// # None, + /// # } + /// # + /// # use self::Option::{Some, None}; + /// # + /// impl<T> Serialize for Option<T> + /// where + /// T: Serialize, + /// { + /// fn serialize<S>(&self, serializer: S) -> Result<S::Ok, S::Error> + /// where + /// S: Serializer, + /// { + /// match *self { + /// Some(ref value) => serializer.serialize_some(value), + /// None => serializer.serialize_none(), + /// } + /// } + /// } + /// # + /// # fn main() {} + /// ``` + /// + /// [`None`]: https://doc.rust-lang.org/std/option/enum.Option.html#variant.None + fn serialize_none(self) -> Result<Self::Ok, Self::Error>; + + /// Serialize a [`Some(T)`] value. + /// + /// ```edition2018 + /// # use serde::{Serialize, Serializer}; + /// # + /// # enum Option<T> { + /// # Some(T), + /// # None, + /// # } + /// # + /// # use self::Option::{Some, None}; + /// # + /// impl<T> Serialize for Option<T> + /// where + /// T: Serialize, + /// { + /// fn serialize<S>(&self, serializer: S) -> Result<S::Ok, S::Error> + /// where + /// S: Serializer, + /// { + /// match *self { + /// Some(ref value) => serializer.serialize_some(value), + /// None => serializer.serialize_none(), + /// } + /// } + /// } + /// # + /// # fn main() {} + /// ``` + /// + /// [`Some(T)`]: https://doc.rust-lang.org/std/option/enum.Option.html#variant.Some + fn serialize_some<T: ?Sized>(self, value: &T) -> Result<Self::Ok, Self::Error> + where + T: Serialize; + + /// Serialize a `()` value. + /// + /// ```edition2018 + /// # use serde::Serializer; + /// # + /// # serde::__private_serialize!(); + /// # + /// impl Serialize for () { + /// fn serialize<S>(&self, serializer: S) -> Result<S::Ok, S::Error> + /// where + /// S: Serializer, + /// { + /// serializer.serialize_unit() + /// } + /// } + /// ``` + fn serialize_unit(self) -> Result<Self::Ok, Self::Error>; + + /// Serialize a unit struct like `struct Unit` or `PhantomData<T>`. + /// + /// A reasonable implementation would be to forward to `serialize_unit`. + /// + /// ```edition2018 + /// use serde::{Serialize, Serializer}; + /// + /// struct Nothing; + /// + /// impl Serialize for Nothing { + /// fn serialize<S>(&self, serializer: S) -> Result<S::Ok, S::Error> + /// where + /// S: Serializer, + /// { + /// serializer.serialize_unit_struct("Nothing") + /// } + /// } + /// ``` + fn serialize_unit_struct(self, name: &'static str) -> Result<Self::Ok, Self::Error>; + + /// Serialize a unit variant like `E::A` in `enum E { A, B }`. + /// + /// The `name` is the name of the enum, the `variant_index` is the index of + /// this variant within the enum, and the `variant` is the name of the + /// variant. + /// + /// ```edition2018 + /// use serde::{Serialize, Serializer}; + /// + /// enum E { + /// A, + /// B, + /// } + /// + /// impl Serialize for E { + /// fn serialize<S>(&self, serializer: S) -> Result<S::Ok, S::Error> + /// where + /// S: Serializer, + /// { + /// match *self { + /// E::A => serializer.serialize_unit_variant("E", 0, "A"), + /// E::B => serializer.serialize_unit_variant("E", 1, "B"), + /// } + /// } + /// } + /// ``` + fn serialize_unit_variant( + self, + name: &'static str, + variant_index: u32, + variant: &'static str, + ) -> Result<Self::Ok, Self::Error>; + + /// Serialize a newtype struct like `struct Millimeters(u8)`. + /// + /// Serializers are encouraged to treat newtype structs as insignificant + /// wrappers around the data they contain. A reasonable implementation would + /// be to forward to `value.serialize(self)`. + /// + /// ```edition2018 + /// use serde::{Serialize, Serializer}; + /// + /// struct Millimeters(u8); + /// + /// impl Serialize for Millimeters { + /// fn serialize<S>(&self, serializer: S) -> Result<S::Ok, S::Error> + /// where + /// S: Serializer, + /// { + /// serializer.serialize_newtype_struct("Millimeters", &self.0) + /// } + /// } + /// ``` + fn serialize_newtype_struct<T: ?Sized>( + self, + name: &'static str, + value: &T, + ) -> Result<Self::Ok, Self::Error> + where + T: Serialize; + + /// Serialize a newtype variant like `E::N` in `enum E { N(u8) }`. + /// + /// The `name` is the name of the enum, the `variant_index` is the index of + /// this variant within the enum, and the `variant` is the name of the + /// variant. The `value` is the data contained within this newtype variant. + /// + /// ```edition2018 + /// use serde::{Serialize, Serializer}; + /// + /// enum E { + /// M(String), + /// N(u8), + /// } + /// + /// impl Serialize for E { + /// fn serialize<S>(&self, serializer: S) -> Result<S::Ok, S::Error> + /// where + /// S: Serializer, + /// { + /// match *self { + /// E::M(ref s) => serializer.serialize_newtype_variant("E", 0, "M", s), + /// E::N(n) => serializer.serialize_newtype_variant("E", 1, "N", &n), + /// } + /// } + /// } + /// ``` + fn serialize_newtype_variant<T: ?Sized>( + self, + name: &'static str, + variant_index: u32, + variant: &'static str, + value: &T, + ) -> Result<Self::Ok, Self::Error> + where + T: Serialize; + + /// Begin to serialize a variably sized sequence. This call must be + /// followed by zero or more calls to `serialize_element`, then a call to + /// `end`. + /// + /// The argument is the number of elements in the sequence, which may or may + /// not be computable before the sequence is iterated. Some serializers only + /// support sequences whose length is known up front. + /// + /// ```edition2018 + /// # use std::marker::PhantomData; + /// # + /// # struct Vec<T>(PhantomData<T>); + /// # + /// # impl<T> Vec<T> { + /// # fn len(&self) -> usize { + /// # unimplemented!() + /// # } + /// # } + /// # + /// # impl<'a, T> IntoIterator for &'a Vec<T> { + /// # type Item = &'a T; + /// # type IntoIter = Box<Iterator<Item = &'a T>>; + /// # + /// # fn into_iter(self) -> Self::IntoIter { + /// # unimplemented!() + /// # } + /// # } + /// # + /// use serde::ser::{Serialize, Serializer, SerializeSeq}; + /// + /// impl<T> Serialize for Vec<T> + /// where + /// T: Serialize, + /// { + /// fn serialize<S>(&self, serializer: S) -> Result<S::Ok, S::Error> + /// where + /// S: Serializer, + /// { + /// let mut seq = serializer.serialize_seq(Some(self.len()))?; + /// for element in self { + /// seq.serialize_element(element)?; + /// } + /// seq.end() + /// } + /// } + /// ``` + fn serialize_seq(self, len: Option<usize>) -> Result<Self::SerializeSeq, Self::Error>; + + /// Begin to serialize a statically sized sequence whose length will be + /// known at deserialization time without looking at the serialized data. + /// This call must be followed by zero or more calls to `serialize_element`, + /// then a call to `end`. + /// + /// ```edition2018 + /// use serde::ser::{Serialize, Serializer, SerializeTuple}; + /// + /// # mod fool { + /// # trait Serialize {} + /// impl<A, B, C> Serialize for (A, B, C) + /// # {} + /// # } + /// # + /// # struct Tuple3<A, B, C>(A, B, C); + /// # + /// # impl<A, B, C> Serialize for Tuple3<A, B, C> + /// where + /// A: Serialize, + /// B: Serialize, + /// C: Serialize, + /// { + /// fn serialize<S>(&self, serializer: S) -> Result<S::Ok, S::Error> + /// where + /// S: Serializer, + /// { + /// let mut tup = serializer.serialize_tuple(3)?; + /// tup.serialize_element(&self.0)?; + /// tup.serialize_element(&self.1)?; + /// tup.serialize_element(&self.2)?; + /// tup.end() + /// } + /// } + /// ``` + /// + /// ```edition2018 + /// use serde::ser::{Serialize, SerializeTuple, Serializer}; + /// + /// const VRAM_SIZE: usize = 386; + /// struct Vram([u16; VRAM_SIZE]); + /// + /// impl Serialize for Vram { + /// fn serialize<S>(&self, serializer: S) -> Result<S::Ok, S::Error> + /// where + /// S: Serializer, + /// { + /// let mut seq = serializer.serialize_tuple(VRAM_SIZE)?; + /// for element in &self.0[..] { + /// seq.serialize_element(element)?; + /// } + /// seq.end() + /// } + /// } + /// ``` + fn serialize_tuple(self, len: usize) -> Result<Self::SerializeTuple, Self::Error>; + + /// Begin to serialize a tuple struct like `struct Rgb(u8, u8, u8)`. This + /// call must be followed by zero or more calls to `serialize_field`, then a + /// call to `end`. + /// + /// The `name` is the name of the tuple struct and the `len` is the number + /// of data fields that will be serialized. + /// + /// ```edition2018 + /// use serde::ser::{Serialize, SerializeTupleStruct, Serializer}; + /// + /// struct Rgb(u8, u8, u8); + /// + /// impl Serialize for Rgb { + /// fn serialize<S>(&self, serializer: S) -> Result<S::Ok, S::Error> + /// where + /// S: Serializer, + /// { + /// let mut ts = serializer.serialize_tuple_struct("Rgb", 3)?; + /// ts.serialize_field(&self.0)?; + /// ts.serialize_field(&self.1)?; + /// ts.serialize_field(&self.2)?; + /// ts.end() + /// } + /// } + /// ``` + fn serialize_tuple_struct( + self, + name: &'static str, + len: usize, + ) -> Result<Self::SerializeTupleStruct, Self::Error>; + + /// Begin to serialize a tuple variant like `E::T` in `enum E { T(u8, u8) + /// }`. This call must be followed by zero or more calls to + /// `serialize_field`, then a call to `end`. + /// + /// The `name` is the name of the enum, the `variant_index` is the index of + /// this variant within the enum, the `variant` is the name of the variant, + /// and the `len` is the number of data fields that will be serialized. + /// + /// ```edition2018 + /// use serde::ser::{Serialize, SerializeTupleVariant, Serializer}; + /// + /// enum E { + /// T(u8, u8), + /// U(String, u32, u32), + /// } + /// + /// impl Serialize for E { + /// fn serialize<S>(&self, serializer: S) -> Result<S::Ok, S::Error> + /// where + /// S: Serializer, + /// { + /// match *self { + /// E::T(ref a, ref b) => { + /// let mut tv = serializer.serialize_tuple_variant("E", 0, "T", 2)?; + /// tv.serialize_field(a)?; + /// tv.serialize_field(b)?; + /// tv.end() + /// } + /// E::U(ref a, ref b, ref c) => { + /// let mut tv = serializer.serialize_tuple_variant("E", 1, "U", 3)?; + /// tv.serialize_field(a)?; + /// tv.serialize_field(b)?; + /// tv.serialize_field(c)?; + /// tv.end() + /// } + /// } + /// } + /// } + /// ``` + fn serialize_tuple_variant( + self, + name: &'static str, + variant_index: u32, + variant: &'static str, + len: usize, + ) -> Result<Self::SerializeTupleVariant, Self::Error>; + + /// Begin to serialize a map. This call must be followed by zero or more + /// calls to `serialize_key` and `serialize_value`, then a call to `end`. + /// + /// The argument is the number of elements in the map, which may or may not + /// be computable before the map is iterated. Some serializers only support + /// maps whose length is known up front. + /// + /// ```edition2018 + /// # use std::marker::PhantomData; + /// # + /// # struct HashMap<K, V>(PhantomData<K>, PhantomData<V>); + /// # + /// # impl<K, V> HashMap<K, V> { + /// # fn len(&self) -> usize { + /// # unimplemented!() + /// # } + /// # } + /// # + /// # impl<'a, K, V> IntoIterator for &'a HashMap<K, V> { + /// # type Item = (&'a K, &'a V); + /// # type IntoIter = Box<Iterator<Item = (&'a K, &'a V)>>; + /// # + /// # fn into_iter(self) -> Self::IntoIter { + /// # unimplemented!() + /// # } + /// # } + /// # + /// use serde::ser::{Serialize, Serializer, SerializeMap}; + /// + /// impl<K, V> Serialize for HashMap<K, V> + /// where + /// K: Serialize, + /// V: Serialize, + /// { + /// fn serialize<S>(&self, serializer: S) -> Result<S::Ok, S::Error> + /// where + /// S: Serializer, + /// { + /// let mut map = serializer.serialize_map(Some(self.len()))?; + /// for (k, v) in self { + /// map.serialize_entry(k, v)?; + /// } + /// map.end() + /// } + /// } + /// ``` + fn serialize_map(self, len: Option<usize>) -> Result<Self::SerializeMap, Self::Error>; + + /// Begin to serialize a struct like `struct Rgb { r: u8, g: u8, b: u8 }`. + /// This call must be followed by zero or more calls to `serialize_field`, + /// then a call to `end`. + /// + /// The `name` is the name of the struct and the `len` is the number of + /// data fields that will be serialized. + /// + /// ```edition2018 + /// use serde::ser::{Serialize, SerializeStruct, Serializer}; + /// + /// struct Rgb { + /// r: u8, + /// g: u8, + /// b: u8, + /// } + /// + /// impl Serialize for Rgb { + /// fn serialize<S>(&self, serializer: S) -> Result<S::Ok, S::Error> + /// where + /// S: Serializer, + /// { + /// let mut rgb = serializer.serialize_struct("Rgb", 3)?; + /// rgb.serialize_field("r", &self.r)?; + /// rgb.serialize_field("g", &self.g)?; + /// rgb.serialize_field("b", &self.b)?; + /// rgb.end() + /// } + /// } + /// ``` + fn serialize_struct( + self, + name: &'static str, + len: usize, + ) -> Result<Self::SerializeStruct, Self::Error>; + + /// Begin to serialize a struct variant like `E::S` in `enum E { S { r: u8, + /// g: u8, b: u8 } }`. This call must be followed by zero or more calls to + /// `serialize_field`, then a call to `end`. + /// + /// The `name` is the name of the enum, the `variant_index` is the index of + /// this variant within the enum, the `variant` is the name of the variant, + /// and the `len` is the number of data fields that will be serialized. + /// + /// ```edition2018 + /// use serde::ser::{Serialize, SerializeStructVariant, Serializer}; + /// + /// enum E { + /// S { r: u8, g: u8, b: u8 }, + /// } + /// + /// impl Serialize for E { + /// fn serialize<S>(&self, serializer: S) -> Result<S::Ok, S::Error> + /// where + /// S: Serializer, + /// { + /// match *self { + /// E::S { + /// ref r, + /// ref g, + /// ref b, + /// } => { + /// let mut sv = serializer.serialize_struct_variant("E", 0, "S", 3)?; + /// sv.serialize_field("r", r)?; + /// sv.serialize_field("g", g)?; + /// sv.serialize_field("b", b)?; + /// sv.end() + /// } + /// } + /// } + /// } + /// ``` + fn serialize_struct_variant( + self, + name: &'static str, + variant_index: u32, + variant: &'static str, + len: usize, + ) -> Result<Self::SerializeStructVariant, Self::Error>; + + /// Collect an iterator as a sequence. + /// + /// The default implementation serializes each item yielded by the iterator + /// using [`serialize_seq`]. Implementors should not need to override this + /// method. + /// + /// ```edition2018 + /// use serde::{Serialize, Serializer}; + /// + /// struct SecretlyOneHigher { + /// data: Vec<i32>, + /// } + /// + /// impl Serialize for SecretlyOneHigher { + /// fn serialize<S>(&self, serializer: S) -> Result<S::Ok, S::Error> + /// where + /// S: Serializer, + /// { + /// serializer.collect_seq(self.data.iter().map(|x| x + 1)) + /// } + /// } + /// ``` + /// + /// [`serialize_seq`]: #tymethod.serialize_seq + fn collect_seq<I>(self, iter: I) -> Result<Self::Ok, Self::Error> + where + I: IntoIterator, + <I as IntoIterator>::Item: Serialize, + { + let iter = iter.into_iter(); + let mut serializer = try!(self.serialize_seq(iterator_len_hint(&iter))); + + #[cfg(not(no_iterator_try_fold))] + { + let mut iter = iter; + try!(iter.try_for_each(|item| serializer.serialize_element(&item))); + } + + #[cfg(no_iterator_try_fold)] + { + for item in iter { + try!(serializer.serialize_element(&item)); + } + } + + serializer.end() + } + + /// Collect an iterator as a map. + /// + /// The default implementation serializes each pair yielded by the iterator + /// using [`serialize_map`]. Implementors should not need to override this + /// method. + /// + /// ```edition2018 + /// use serde::{Serialize, Serializer}; + /// use std::collections::BTreeSet; + /// + /// struct MapToUnit { + /// keys: BTreeSet<i32>, + /// } + /// + /// // Serializes as a map in which the values are all unit. + /// impl Serialize for MapToUnit { + /// fn serialize<S>(&self, serializer: S) -> Result<S::Ok, S::Error> + /// where + /// S: Serializer, + /// { + /// serializer.collect_map(self.keys.iter().map(|k| (k, ()))) + /// } + /// } + /// ``` + /// + /// [`serialize_map`]: #tymethod.serialize_map + fn collect_map<K, V, I>(self, iter: I) -> Result<Self::Ok, Self::Error> + where + K: Serialize, + V: Serialize, + I: IntoIterator<Item = (K, V)>, + { + let iter = iter.into_iter(); + let mut serializer = try!(self.serialize_map(iterator_len_hint(&iter))); + + #[cfg(not(no_iterator_try_fold))] + { + let mut iter = iter; + try!(iter.try_for_each(|(key, value)| serializer.serialize_entry(&key, &value))); + } + + #[cfg(no_iterator_try_fold)] + { + for (key, value) in iter { + try!(serializer.serialize_entry(&key, &value)); + } + } + + serializer.end() + } + + /// Serialize a string produced by an implementation of `Display`. + /// + /// The default implementation builds a heap-allocated [`String`] and + /// delegates to [`serialize_str`]. Serializers are encouraged to provide a + /// more efficient implementation if possible. + /// + /// ```edition2018 + /// # struct DateTime; + /// # + /// # impl DateTime { + /// # fn naive_local(&self) -> () { () } + /// # fn offset(&self) -> () { () } + /// # } + /// # + /// use serde::{Serialize, Serializer}; + /// + /// impl Serialize for DateTime { + /// fn serialize<S>(&self, serializer: S) -> Result<S::Ok, S::Error> + /// where + /// S: Serializer, + /// { + /// serializer.collect_str(&format_args!("{:?}{:?}", + /// self.naive_local(), + /// self.offset())) + /// } + /// } + /// ``` + /// + /// [`String`]: https://doc.rust-lang.org/std/string/struct.String.html + /// [`serialize_str`]: #tymethod.serialize_str + #[cfg(any(feature = "std", feature = "alloc"))] + fn collect_str<T: ?Sized>(self, value: &T) -> Result<Self::Ok, Self::Error> + where + T: Display, + { + self.serialize_str(&value.to_string()) + } + + /// Serialize a string produced by an implementation of `Display`. + /// + /// Serializers that use `no_std` are required to provide an implementation + /// of this method. If no more sensible behavior is possible, the + /// implementation is expected to return an error. + /// + /// ```edition2018 + /// # struct DateTime; + /// # + /// # impl DateTime { + /// # fn naive_local(&self) -> () { () } + /// # fn offset(&self) -> () { () } + /// # } + /// # + /// use serde::{Serialize, Serializer}; + /// + /// impl Serialize for DateTime { + /// fn serialize<S>(&self, serializer: S) -> Result<S::Ok, S::Error> + /// where + /// S: Serializer, + /// { + /// serializer.collect_str(&format_args!("{:?}{:?}", + /// self.naive_local(), + /// self.offset())) + /// } + /// } + /// ``` + #[cfg(not(any(feature = "std", feature = "alloc")))] + fn collect_str<T: ?Sized>(self, value: &T) -> Result<Self::Ok, Self::Error> + where + T: Display; + + /// Determine whether `Serialize` implementations should serialize in + /// human-readable form. + /// + /// Some types have a human-readable form that may be somewhat expensive to + /// construct, as well as a binary form that is compact and efficient. + /// Generally text-based formats like JSON and YAML will prefer to use the + /// human-readable one and binary formats like Postcard will prefer the + /// compact one. + /// + /// ```edition2018 + /// # use std::fmt::{self, Display}; + /// # + /// # struct Timestamp; + /// # + /// # impl Timestamp { + /// # fn seconds_since_epoch(&self) -> u64 { unimplemented!() } + /// # } + /// # + /// # impl Display for Timestamp { + /// # fn fmt(&self, formatter: &mut fmt::Formatter) -> fmt::Result { + /// # unimplemented!() + /// # } + /// # } + /// # + /// use serde::{Serialize, Serializer}; + /// + /// impl Serialize for Timestamp { + /// fn serialize<S>(&self, serializer: S) -> Result<S::Ok, S::Error> + /// where + /// S: Serializer, + /// { + /// if serializer.is_human_readable() { + /// // Serialize to a human-readable string "2015-05-15T17:01:00Z". + /// self.to_string().serialize(serializer) + /// } else { + /// // Serialize to a compact binary representation. + /// self.seconds_since_epoch().serialize(serializer) + /// } + /// } + /// } + /// ``` + /// + /// The default implementation of this method returns `true`. Data formats + /// may override this to `false` to request a compact form for types that + /// support one. Note that modifying this method to change a format from + /// human-readable to compact or vice versa should be regarded as a breaking + /// change, as a value serialized in human-readable mode is not required to + /// deserialize from the same data in compact mode. + #[inline] + fn is_human_readable(&self) -> bool { + true + } +} + +/// Returned from `Serializer::serialize_seq`. +/// +/// # Example use +/// +/// ```edition2018 +/// # use std::marker::PhantomData; +/// # +/// # struct Vec<T>(PhantomData<T>); +/// # +/// # impl<T> Vec<T> { +/// # fn len(&self) -> usize { +/// # unimplemented!() +/// # } +/// # } +/// # +/// # impl<'a, T> IntoIterator for &'a Vec<T> { +/// # type Item = &'a T; +/// # type IntoIter = Box<Iterator<Item = &'a T>>; +/// # fn into_iter(self) -> Self::IntoIter { +/// # unimplemented!() +/// # } +/// # } +/// # +/// use serde::ser::{Serialize, Serializer, SerializeSeq}; +/// +/// impl<T> Serialize for Vec<T> +/// where +/// T: Serialize, +/// { +/// fn serialize<S>(&self, serializer: S) -> Result<S::Ok, S::Error> +/// where +/// S: Serializer, +/// { +/// let mut seq = serializer.serialize_seq(Some(self.len()))?; +/// for element in self { +/// seq.serialize_element(element)?; +/// } +/// seq.end() +/// } +/// } +/// ``` +/// +/// # Example implementation +/// +/// The [example data format] presented on the website demonstrates an +/// implementation of `SerializeSeq` for a basic JSON data format. +/// +/// [example data format]: https://serde.rs/data-format.html +pub trait SerializeSeq { + /// Must match the `Ok` type of our `Serializer`. + type Ok; + + /// Must match the `Error` type of our `Serializer`. + type Error: Error; + + /// Serialize a sequence element. + fn serialize_element<T: ?Sized>(&mut self, value: &T) -> Result<(), Self::Error> + where + T: Serialize; + + /// Finish serializing a sequence. + fn end(self) -> Result<Self::Ok, Self::Error>; +} + +/// Returned from `Serializer::serialize_tuple`. +/// +/// # Example use +/// +/// ```edition2018 +/// use serde::ser::{Serialize, Serializer, SerializeTuple}; +/// +/// # mod fool { +/// # trait Serialize {} +/// impl<A, B, C> Serialize for (A, B, C) +/// # {} +/// # } +/// # +/// # struct Tuple3<A, B, C>(A, B, C); +/// # +/// # impl<A, B, C> Serialize for Tuple3<A, B, C> +/// where +/// A: Serialize, +/// B: Serialize, +/// C: Serialize, +/// { +/// fn serialize<S>(&self, serializer: S) -> Result<S::Ok, S::Error> +/// where +/// S: Serializer, +/// { +/// let mut tup = serializer.serialize_tuple(3)?; +/// tup.serialize_element(&self.0)?; +/// tup.serialize_element(&self.1)?; +/// tup.serialize_element(&self.2)?; +/// tup.end() +/// } +/// } +/// ``` +/// +/// ```edition2018 +/// # use std::marker::PhantomData; +/// # +/// # struct Array<T>(PhantomData<T>); +/// # +/// # impl<T> Array<T> { +/// # fn len(&self) -> usize { +/// # unimplemented!() +/// # } +/// # } +/// # +/// # impl<'a, T> IntoIterator for &'a Array<T> { +/// # type Item = &'a T; +/// # type IntoIter = Box<Iterator<Item = &'a T>>; +/// # fn into_iter(self) -> Self::IntoIter { +/// # unimplemented!() +/// # } +/// # } +/// # +/// use serde::ser::{Serialize, Serializer, SerializeTuple}; +/// +/// # mod fool { +/// # trait Serialize {} +/// impl<T> Serialize for [T; 16] +/// # {} +/// # } +/// # +/// # impl<T> Serialize for Array<T> +/// where +/// T: Serialize, +/// { +/// fn serialize<S>(&self, serializer: S) -> Result<S::Ok, S::Error> +/// where +/// S: Serializer, +/// { +/// let mut seq = serializer.serialize_tuple(16)?; +/// for element in self { +/// seq.serialize_element(element)?; +/// } +/// seq.end() +/// } +/// } +/// ``` +/// +/// # Example implementation +/// +/// The [example data format] presented on the website demonstrates an +/// implementation of `SerializeTuple` for a basic JSON data format. +/// +/// [example data format]: https://serde.rs/data-format.html +pub trait SerializeTuple { + /// Must match the `Ok` type of our `Serializer`. + type Ok; + + /// Must match the `Error` type of our `Serializer`. + type Error: Error; + + /// Serialize a tuple element. + fn serialize_element<T: ?Sized>(&mut self, value: &T) -> Result<(), Self::Error> + where + T: Serialize; + + /// Finish serializing a tuple. + fn end(self) -> Result<Self::Ok, Self::Error>; +} + +/// Returned from `Serializer::serialize_tuple_struct`. +/// +/// # Example use +/// +/// ```edition2018 +/// use serde::ser::{Serialize, SerializeTupleStruct, Serializer}; +/// +/// struct Rgb(u8, u8, u8); +/// +/// impl Serialize for Rgb { +/// fn serialize<S>(&self, serializer: S) -> Result<S::Ok, S::Error> +/// where +/// S: Serializer, +/// { +/// let mut ts = serializer.serialize_tuple_struct("Rgb", 3)?; +/// ts.serialize_field(&self.0)?; +/// ts.serialize_field(&self.1)?; +/// ts.serialize_field(&self.2)?; +/// ts.end() +/// } +/// } +/// ``` +/// +/// # Example implementation +/// +/// The [example data format] presented on the website demonstrates an +/// implementation of `SerializeTupleStruct` for a basic JSON data format. +/// +/// [example data format]: https://serde.rs/data-format.html +pub trait SerializeTupleStruct { + /// Must match the `Ok` type of our `Serializer`. + type Ok; + + /// Must match the `Error` type of our `Serializer`. + type Error: Error; + + /// Serialize a tuple struct field. + fn serialize_field<T: ?Sized>(&mut self, value: &T) -> Result<(), Self::Error> + where + T: Serialize; + + /// Finish serializing a tuple struct. + fn end(self) -> Result<Self::Ok, Self::Error>; +} + +/// Returned from `Serializer::serialize_tuple_variant`. +/// +/// # Example use +/// +/// ```edition2018 +/// use serde::ser::{Serialize, SerializeTupleVariant, Serializer}; +/// +/// enum E { +/// T(u8, u8), +/// U(String, u32, u32), +/// } +/// +/// impl Serialize for E { +/// fn serialize<S>(&self, serializer: S) -> Result<S::Ok, S::Error> +/// where +/// S: Serializer, +/// { +/// match *self { +/// E::T(ref a, ref b) => { +/// let mut tv = serializer.serialize_tuple_variant("E", 0, "T", 2)?; +/// tv.serialize_field(a)?; +/// tv.serialize_field(b)?; +/// tv.end() +/// } +/// E::U(ref a, ref b, ref c) => { +/// let mut tv = serializer.serialize_tuple_variant("E", 1, "U", 3)?; +/// tv.serialize_field(a)?; +/// tv.serialize_field(b)?; +/// tv.serialize_field(c)?; +/// tv.end() +/// } +/// } +/// } +/// } +/// ``` +/// +/// # Example implementation +/// +/// The [example data format] presented on the website demonstrates an +/// implementation of `SerializeTupleVariant` for a basic JSON data format. +/// +/// [example data format]: https://serde.rs/data-format.html +pub trait SerializeTupleVariant { + /// Must match the `Ok` type of our `Serializer`. + type Ok; + + /// Must match the `Error` type of our `Serializer`. + type Error: Error; + + /// Serialize a tuple variant field. + fn serialize_field<T: ?Sized>(&mut self, value: &T) -> Result<(), Self::Error> + where + T: Serialize; + + /// Finish serializing a tuple variant. + fn end(self) -> Result<Self::Ok, Self::Error>; +} + +/// Returned from `Serializer::serialize_map`. +/// +/// # Example use +/// +/// ```edition2018 +/// # use std::marker::PhantomData; +/// # +/// # struct HashMap<K, V>(PhantomData<K>, PhantomData<V>); +/// # +/// # impl<K, V> HashMap<K, V> { +/// # fn len(&self) -> usize { +/// # unimplemented!() +/// # } +/// # } +/// # +/// # impl<'a, K, V> IntoIterator for &'a HashMap<K, V> { +/// # type Item = (&'a K, &'a V); +/// # type IntoIter = Box<Iterator<Item = (&'a K, &'a V)>>; +/// # +/// # fn into_iter(self) -> Self::IntoIter { +/// # unimplemented!() +/// # } +/// # } +/// # +/// use serde::ser::{Serialize, Serializer, SerializeMap}; +/// +/// impl<K, V> Serialize for HashMap<K, V> +/// where +/// K: Serialize, +/// V: Serialize, +/// { +/// fn serialize<S>(&self, serializer: S) -> Result<S::Ok, S::Error> +/// where +/// S: Serializer, +/// { +/// let mut map = serializer.serialize_map(Some(self.len()))?; +/// for (k, v) in self { +/// map.serialize_entry(k, v)?; +/// } +/// map.end() +/// } +/// } +/// ``` +/// +/// # Example implementation +/// +/// The [example data format] presented on the website demonstrates an +/// implementation of `SerializeMap` for a basic JSON data format. +/// +/// [example data format]: https://serde.rs/data-format.html +pub trait SerializeMap { + /// Must match the `Ok` type of our `Serializer`. + type Ok; + + /// Must match the `Error` type of our `Serializer`. + type Error: Error; + + /// Serialize a map key. + /// + /// If possible, `Serialize` implementations are encouraged to use + /// `serialize_entry` instead as it may be implemented more efficiently in + /// some formats compared to a pair of calls to `serialize_key` and + /// `serialize_value`. + fn serialize_key<T: ?Sized>(&mut self, key: &T) -> Result<(), Self::Error> + where + T: Serialize; + + /// Serialize a map value. + /// + /// # Panics + /// + /// Calling `serialize_value` before `serialize_key` is incorrect and is + /// allowed to panic or produce bogus results. + fn serialize_value<T: ?Sized>(&mut self, value: &T) -> Result<(), Self::Error> + where + T: Serialize; + + /// Serialize a map entry consisting of a key and a value. + /// + /// Some [`Serialize`] types are not able to hold a key and value in memory + /// at the same time so `SerializeMap` implementations are required to + /// support [`serialize_key`] and [`serialize_value`] individually. The + /// `serialize_entry` method allows serializers to optimize for the case + /// where key and value are both available. [`Serialize`] implementations + /// are encouraged to use `serialize_entry` if possible. + /// + /// The default implementation delegates to [`serialize_key`] and + /// [`serialize_value`]. This is appropriate for serializers that do not + /// care about performance or are not able to optimize `serialize_entry` any + /// better than this. + /// + /// [`Serialize`]: ../trait.Serialize.html + /// [`serialize_key`]: #tymethod.serialize_key + /// [`serialize_value`]: #tymethod.serialize_value + fn serialize_entry<K: ?Sized, V: ?Sized>( + &mut self, + key: &K, + value: &V, + ) -> Result<(), Self::Error> + where + K: Serialize, + V: Serialize, + { + try!(self.serialize_key(key)); + self.serialize_value(value) + } + + /// Finish serializing a map. + fn end(self) -> Result<Self::Ok, Self::Error>; +} + +/// Returned from `Serializer::serialize_struct`. +/// +/// # Example use +/// +/// ```edition2018 +/// use serde::ser::{Serialize, SerializeStruct, Serializer}; +/// +/// struct Rgb { +/// r: u8, +/// g: u8, +/// b: u8, +/// } +/// +/// impl Serialize for Rgb { +/// fn serialize<S>(&self, serializer: S) -> Result<S::Ok, S::Error> +/// where +/// S: Serializer, +/// { +/// let mut rgb = serializer.serialize_struct("Rgb", 3)?; +/// rgb.serialize_field("r", &self.r)?; +/// rgb.serialize_field("g", &self.g)?; +/// rgb.serialize_field("b", &self.b)?; +/// rgb.end() +/// } +/// } +/// ``` +/// +/// # Example implementation +/// +/// The [example data format] presented on the website demonstrates an +/// implementation of `SerializeStruct` for a basic JSON data format. +/// +/// [example data format]: https://serde.rs/data-format.html +pub trait SerializeStruct { + /// Must match the `Ok` type of our `Serializer`. + type Ok; + + /// Must match the `Error` type of our `Serializer`. + type Error: Error; + + /// Serialize a struct field. + fn serialize_field<T: ?Sized>( + &mut self, + key: &'static str, + value: &T, + ) -> Result<(), Self::Error> + where + T: Serialize; + + /// Indicate that a struct field has been skipped. + #[inline] + fn skip_field(&mut self, key: &'static str) -> Result<(), Self::Error> { + let _ = key; + Ok(()) + } + + /// Finish serializing a struct. + fn end(self) -> Result<Self::Ok, Self::Error>; +} + +/// Returned from `Serializer::serialize_struct_variant`. +/// +/// # Example use +/// +/// ```edition2018 +/// use serde::ser::{Serialize, SerializeStructVariant, Serializer}; +/// +/// enum E { +/// S { r: u8, g: u8, b: u8 }, +/// } +/// +/// impl Serialize for E { +/// fn serialize<S>(&self, serializer: S) -> Result<S::Ok, S::Error> +/// where +/// S: Serializer, +/// { +/// match *self { +/// E::S { +/// ref r, +/// ref g, +/// ref b, +/// } => { +/// let mut sv = serializer.serialize_struct_variant("E", 0, "S", 3)?; +/// sv.serialize_field("r", r)?; +/// sv.serialize_field("g", g)?; +/// sv.serialize_field("b", b)?; +/// sv.end() +/// } +/// } +/// } +/// } +/// ``` +/// +/// # Example implementation +/// +/// The [example data format] presented on the website demonstrates an +/// implementation of `SerializeStructVariant` for a basic JSON data format. +/// +/// [example data format]: https://serde.rs/data-format.html +pub trait SerializeStructVariant { + /// Must match the `Ok` type of our `Serializer`. + type Ok; + + /// Must match the `Error` type of our `Serializer`. + type Error: Error; + + /// Serialize a struct variant field. + fn serialize_field<T: ?Sized>( + &mut self, + key: &'static str, + value: &T, + ) -> Result<(), Self::Error> + where + T: Serialize; + + /// Indicate that a struct variant field has been skipped. + #[inline] + fn skip_field(&mut self, key: &'static str) -> Result<(), Self::Error> { + let _ = key; + Ok(()) + } + + /// Finish serializing a struct variant. + fn end(self) -> Result<Self::Ok, Self::Error>; +} + +fn iterator_len_hint<I>(iter: &I) -> Option<usize> +where + I: Iterator, +{ + match iter.size_hint() { + (lo, Some(hi)) if lo == hi => Some(lo), + _ => None, + } +} diff --git a/src/std_error.rs b/src/std_error.rs new file mode 100644 index 0000000..1055e0f --- /dev/null +++ b/src/std_error.rs @@ -0,0 +1,48 @@ +use lib::{Debug, Display}; + +/// Either a re-export of std::error::Error or a new identical trait, depending +/// on whether Serde's "std" feature is enabled. +/// +/// Serde's error traits [`serde::ser::Error`] and [`serde::de::Error`] require +/// [`std::error::Error`] as a supertrait, but only when Serde is built with +/// "std" enabled. Data formats that don't care about no\_std support should +/// generally provide their error types with a `std::error::Error` impl +/// directly: +/// +/// ```edition2018 +/// #[derive(Debug)] +/// struct MySerError {...} +/// +/// impl serde::ser::Error for MySerError {...} +/// +/// impl std::fmt::Display for MySerError {...} +/// +/// // We don't support no_std! +/// impl std::error::Error for MySerError {} +/// ``` +/// +/// Data formats that *do* support no\_std may either have a "std" feature of +/// their own: +/// +/// ```toml +/// [features] +/// std = ["serde/std"] +/// ``` +/// +/// ```edition2018 +/// #[cfg(feature = "std")] +/// impl std::error::Error for MySerError {} +/// ``` +/// +/// ... or else provide the std Error impl unconditionally via Serde's +/// re-export: +/// +/// ```edition2018 +/// impl serde::ser::StdError for MySerError {} +/// ``` +pub trait Error: Debug + Display { + /// The underlying cause of this error, if any. + fn source(&self) -> Option<&(Error + 'static)> { + None + } +} |