Import rustc_version 0.4.0upstream/0.4.0upstream

12 files changed, 1317 insertions, 0 deletions

diff --git a/.cargo_vcs_info.json b/.cargo_vcs_info.json
new file mode 100644
index 0000000..c0d69af
--- /dev/null
+++ b/.cargo_vcs_info.json
@@ -0,0 +1,5 @@
+{
+  "git": {
+    "sha1": "6093aa9de6428df2e1c04aa9e969f1af7c34664f"
+  }
+}
diff --git a/.github/dependabot.yml b/.github/dependabot.yml
new file mode 100644
index 0000000..93a4164
--- /dev/null
+++ b/.github/dependabot.yml
@@ -0,0 +1,12 @@
+version: 2
+updates:
+- package-ecosystem: cargo
+  directory: "/"
+  schedule:
+    interval: daily
+    time: "04:00"
+  open-pull-requests-limit: 10
+  ignore:
+  - dependency-name: semver
+    versions:
+    - "> 1.0, < 2"
diff --git a/.github/workflows/rust.yml b/.github/workflows/rust.yml
new file mode 100644
index 0000000..6a1c4f8
--- /dev/null
+++ b/.github/workflows/rust.yml
@@ -0,0 +1,70 @@
+name: CI
+
+on:
+  push:
+    branches: ['master']
+  pull_request:
+
+jobs:
+  test:
+    strategy:
+      matrix:
+        os: [ubuntu-latest, macos-latest, windows-latest]
+        rust: [stable, beta, nightly, 1.32.0]
+        exclude:
+          - os: macos-latest
+            rust: beta
+          - os: windows-latest
+            rust: beta
+          - os: macos-latest
+            rust: nightly
+          - os: windows-latest
+            rust: nightly
+          - os: macos-latest
+            rust: 1.32.0
+          - os: windows-latest
+            rust: 1.32.0
+
+    runs-on: ${{ matrix.os }}
+
+    steps:
+      - uses: actions/checkout@v2
+      - uses: actions-rs/toolchain@v1
+        with:
+          profile: minimal
+          toolchain: ${{ matrix.rust }}
+          override: true
+      - uses: actions-rs/cargo@v1
+        with:
+          command: build
+          args: --all-features --all-targets
+      - uses: actions-rs/cargo@v1
+        with:
+          command: test
+          args: --all-features
+
+  lint:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v2
+      - uses: actions-rs/toolchain@v1
+        with:
+          profile: minimal
+          toolchain: stable
+          override: true
+          components: rustfmt, clippy
+      - uses: actions-rs/cargo@v1
+        with:
+          command: fmt
+          args: --all -- --check
+      - uses: actions-rs/cargo@v1
+        if: always()
+        with:
+          command: clippy
+          args: --all-targets --all-features -- -D warnings
+
+  audit:
+    runs-on: ubuntu-latest
+    steps:
+    - uses: actions/checkout@v2
+    - uses: EmbarkStudios/cargo-deny-action@v1
diff --git a/.gitignore b/.gitignore
new file mode 100644
index 0000000..22d9b57
--- /dev/null
+++ b/.gitignore
@@ -0,0 +1,3 @@
+target
+Cargo.lock
+.DS_Store
diff --git a/Cargo.toml b/Cargo.toml
new file mode 100644
index 0000000..c81ff85
--- /dev/null
+++ b/Cargo.toml
@@ -0,0 +1,27 @@
+# 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 believe there's an error in this file please file an
+# issue against the rust-lang/cargo repository. If you're
+# editing this file be aware that the upstream Cargo.toml
+# will likely look very different (and much more reasonable)
+
+[package]
+edition = "2018"
+name = "rustc_version"
+version = "0.4.0"
+authors = ["Dirkjan Ochtman <dirkjan@ochtman.nl>", "Marvin Löbel <loebel.marvin@gmail.com>"]
+description = "A library for querying the version of a installed rustc compiler"
+documentation = "https://docs.rs/rustc_version/"
+readme = "README.md"
+keywords = ["version", "rustc"]
+license = "MIT/Apache-2.0"
+repository = "https://github.com/Kimundi/rustc-version-rs"
+[dependencies.semver]
+version = "1.0"
+[dev-dependencies.doc-comment]
+version = "0.3"
diff --git a/Cargo.toml.orig b/Cargo.toml.orig
new file mode 100644
index 0000000..464176f
--- /dev/null
+++ b/Cargo.toml.orig
@@ -0,0 +1,17 @@
+[package]
+name = "rustc_version"
+version = "0.4.0"
+authors = ["Dirkjan Ochtman <dirkjan@ochtman.nl>", "Marvin Löbel <loebel.marvin@gmail.com>"]
+license = "MIT/Apache-2.0"
+description = "A library for querying the version of a installed rustc compiler"
+readme = "README.md"
+documentation = "https://docs.rs/rustc_version/"
+repository = "https://github.com/Kimundi/rustc-version-rs"
+keywords = ["version", "rustc"]
+edition = "2018"
+
+[dependencies]
+semver = "1.0"
+
+[dev-dependencies]
+doc-comment = "0.3"
diff --git a/LICENSE-APACHE b/LICENSE-APACHE
new file mode 100644
index 0000000..16fe87b
--- /dev/null
+++ b/LICENSE-APACHE
@@ -0,0 +1,201 @@
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diff --git a/LICENSE-MIT b/LICENSE-MIT
new file mode 100644
index 0000000..40b8817
--- /dev/null
+++ b/LICENSE-MIT
@@ -0,0 +1,25 @@
+Copyright (c) 2016 The Rust Project Developers
+
+Permission is hereby granted, free of charge, to any
+person obtaining a copy of this software and associated
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+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..e76ef95
--- /dev/null
+++ b/README.md
@@ -0,0 +1,81 @@
+rustc-version-rs
+================
+
+[![Documentation](https://docs.rs/rustc_version/badge.svg)](https://docs.rs/rustc_version/)
+[![Crates.io](https://img.shields.io/crates/v/rustc_version.svg)](https://crates.io/crates/rustc_version)
+[![Build status](https://github.com/Kimundi/rustc-version-rs/workflows/CI/badge.svg)](https://github.com/Kimundi/rustc-version-rs/actions?query=workflow%3ACI)
+
+A library for querying the version of a `rustc` compiler.
+
+This can be used by build scripts or other tools dealing with Rust sources
+to make decisions based on the version of the compiler. Current MSRV is 1.32.0.
+
+If this is of interest, also consider looking at these other crates:
+
+* [autocfg](https://crates.io/crates/autocfg/), which helps with feature detection instead of depending on compiler versions
+* [rustversion](https://github.com/dtolnay/rustversion) provides a procedural macro with no other dependencies
+
+# Getting Started
+
+[rustc-version-rs is available on crates.io](https://crates.io/crates/rustc_version).
+It is recommended to look there for the newest released version, as well as links to the newest builds of the docs.
+
+At the point of the last update of this README, the latest published version could be used like this:
+
+Add the following dependency to your Cargo manifest...
+
+```toml
+[build-dependencies]
+rustc_version = "0.2"
+```
+
+... and see the [docs](https://docs.rs/rustc_version) for how to use it.
+
+# Example
+
+```rust
+// This could be a cargo build script
+
+use rustc_version::{version, version_meta, Channel, Version};
+
+fn main() {
+    // Assert we haven't travelled back in time
+    assert!(version().unwrap().major >= 1);
+
+    // Set cfg flags depending on release channel
+    match version_meta().unwrap().channel {
+        Channel::Stable => {
+            println!("cargo:rustc-cfg=RUSTC_IS_STABLE");
+        }
+        Channel::Beta => {
+            println!("cargo:rustc-cfg=RUSTC_IS_BETA");
+        }
+        Channel::Nightly => {
+            println!("cargo:rustc-cfg=RUSTC_IS_NIGHTLY");
+        }
+        Channel::Dev => {
+            println!("cargo:rustc-cfg=RUSTC_IS_DEV");
+        }
+    }
+
+    // Check for a minimum version
+    if version().unwrap() >= Version::parse("1.4.0").unwrap() {
+        println!("cargo:rustc-cfg=compiler_has_important_bugfix");
+    }
+}
+```
+
+## License
+
+Licensed under either of
+
+ * Apache License, Version 2.0 ([LICENSE-APACHE](LICENSE-APACHE) or http://www.apache.org/licenses/LICENSE-2.0)
+ * MIT license ([LICENSE-MIT](LICENSE-MIT) or http://opensource.org/licenses/MIT)
+
+at your option.
+
+### Contribution
+
+Unless you explicitly state otherwise, any contribution intentionally submitted
+for inclusion in the work by you, as defined in the Apache-2.0 license, shall be dual licensed as above, without any
+additional terms or conditions.
diff --git a/deny.toml b/deny.toml
new file mode 100644
index 0000000..38c47a8
--- /dev/null
+++ b/deny.toml
@@ -0,0 +1,3 @@
+[licenses]
+allow-osi-fsf-free = "either"
+copyleft = "deny"
diff --git a/src/lib.rs b/src/lib.rs
new file mode 100644
index 0000000..cee1ec8
--- /dev/null
+++ b/src/lib.rs
@@ -0,0 +1,417 @@
+// Copyright 2016 rustc-version-rs developers
+//
+// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
+// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
+// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
+// option. This file may not be copied, modified, or distributed
+// except according to those terms.
+
+#![warn(missing_docs)]
+
+//! Simple library for getting the version information of a `rustc`
+//! compiler.
+//!
+//! This can be used by build scripts or other tools dealing with Rust sources
+//! to make decisions based on the version of the compiler.
+//!
+//! It calls `$RUSTC --version -v` and parses the output, falling
+//! back to `rustc` if `$RUSTC` is not set.
+//!
+//! # Example
+//!
+//! ```rust
+//! // This could be a cargo build script
+//!
+//! use rustc_version::{version, version_meta, Channel, Version};
+//!
+//! // Assert we haven't travelled back in time
+//! assert!(version().unwrap().major >= 1);
+//!
+//! // Set cfg flags depending on release channel
+//! match version_meta().unwrap().channel {
+//!     Channel::Stable => {
+//!         println!("cargo:rustc-cfg=RUSTC_IS_STABLE");
+//!     }
+//!     Channel::Beta => {
+//!         println!("cargo:rustc-cfg=RUSTC_IS_BETA");
+//!     }
+//!     Channel::Nightly => {
+//!         println!("cargo:rustc-cfg=RUSTC_IS_NIGHTLY");
+//!     }
+//!     Channel::Dev => {
+//!         println!("cargo:rustc-cfg=RUSTC_IS_DEV");
+//!     }
+//! }
+//!
+//! // Check for a minimum version
+//! if version().unwrap() >= Version::parse("1.4.0").unwrap() {
+//!     println!("cargo:rustc-cfg=compiler_has_important_bugfix");
+//! }
+//! ```
+
+#[cfg(test)]
+#[macro_use]
+extern crate doc_comment;
+
+#[cfg(test)]
+doctest!("../README.md");
+
+use std::collections::HashMap;
+use std::process::Command;
+use std::{env, error, fmt, io, num, str};
+use std::{ffi::OsString, str::FromStr};
+
+// Convenience re-export to allow version comparison without needing to add
+// semver crate.
+pub use semver::Version;
+
+use Error::*;
+
+/// Release channel of the compiler.
+#[derive(Copy, Clone, Eq, PartialEq, Ord, PartialOrd, Hash, Debug)]
+pub enum Channel {
+    /// Development release channel
+    Dev,
+    /// Nightly release channel
+    Nightly,
+    /// Beta release channel
+    Beta,
+    /// Stable release channel
+    Stable,
+}
+
+/// LLVM version
+///
+/// LLVM's version numbering scheme is not semver compatible until version 4.0
+///
+/// rustc [just prints the major and minor versions], so other parts of the version are not included.
+///
+/// [just prints the major and minor versions]: https://github.com/rust-lang/rust/blob/b5c9e2448c9ace53ad5c11585803894651b18b0a/compiler/rustc_codegen_llvm/src/llvm_util.rs#L173-L178
+#[derive(Clone, Debug, Eq, PartialEq, Ord, PartialOrd, Hash)]
+pub struct LlvmVersion {
+    // fields must be ordered major, minor for comparison to be correct
+    /// Major version
+    pub major: u64,
+    /// Minor version
+    pub minor: u64,
+    // TODO: expose micro version here
+}
+
+impl fmt::Display for LlvmVersion {
+    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+        write!(f, "{}.{}", self.major, self.minor)
+    }
+}
+
+impl FromStr for LlvmVersion {
+    type Err = LlvmVersionParseError;
+
+    fn from_str(s: &str) -> Result<Self, Self::Err> {
+        let mut parts = s
+            .split('.')
+            .map(|part| -> Result<u64, LlvmVersionParseError> {
+                if part == "0" {
+                    Ok(0)
+                } else if part.starts_with('0') {
+                    Err(LlvmVersionParseError::ComponentMustNotHaveLeadingZeros)
+                } else if part.starts_with('-') || part.starts_with('+') {
+                    Err(LlvmVersionParseError::ComponentMustNotHaveSign)
+                } else {
+                    Ok(part.parse()?)
+                }
+            });
+
+        let major = parts.next().unwrap()?;
+        let mut minor = 0;
+
+        if let Some(part) = parts.next() {
+            minor = part?;
+        } else if major < 4 {
+            // LLVM versions earlier than 4.0 have significant minor versions, so require the minor version in this case.
+            return Err(LlvmVersionParseError::MinorVersionRequiredBefore4);
+        }
+
+        if let Some(Err(e)) = parts.next() {
+            return Err(e);
+        }
+
+        if parts.next().is_some() {
+            return Err(LlvmVersionParseError::TooManyComponents);
+        }
+
+        Ok(Self { major, minor })
+    }
+}
+
+/// Rustc version plus metadata like git short hash and build date.
+#[derive(Clone, Debug, Eq, PartialEq, Ord, PartialOrd, Hash)]
+pub struct VersionMeta {
+    /// Version of the compiler
+    pub semver: Version,
+
+    /// Git short hash of the build of the compiler
+    pub commit_hash: Option<String>,
+
+    /// Commit date of the compiler
+    pub commit_date: Option<String>,
+
+    /// Build date of the compiler; this was removed between Rust 1.0.0 and 1.1.0.
+    pub build_date: Option<String>,
+
+    /// Release channel of the compiler
+    pub channel: Channel,
+
+    /// Host target triple of the compiler
+    pub host: String,
+
+    /// Short version string of the compiler
+    pub short_version_string: String,
+
+    /// Version of LLVM used by the compiler
+    pub llvm_version: Option<LlvmVersion>,
+}
+
+impl VersionMeta {
+    /// Returns the version metadata for `cmd`, which should be a `rustc` command.
+    pub fn for_command(mut cmd: Command) -> Result<VersionMeta> {
+        let out = cmd
+            .arg("-vV")
+            .output()
+            .map_err(Error::CouldNotExecuteCommand)?;
+
+        if !out.status.success() {
+            return Err(Error::CommandError {
+                stdout: String::from_utf8_lossy(&out.stdout).into(),
+                stderr: String::from_utf8_lossy(&out.stderr).into(),
+            });
+        }
+
+        version_meta_for(str::from_utf8(&out.stdout)?)
+    }
+}
+
+/// Returns the `rustc` SemVer version.
+pub fn version() -> Result<Version> {
+    Ok(version_meta()?.semver)
+}
+
+/// Returns the `rustc` SemVer version and additional metadata
+/// like the git short hash and build date.
+pub fn version_meta() -> Result<VersionMeta> {
+    let cmd = env::var_os("RUSTC").unwrap_or_else(|| OsString::from("rustc"));
+
+    VersionMeta::for_command(Command::new(cmd))
+}
+
+/// Parses a "rustc -vV" output string and returns
+/// the SemVer version and additional metadata
+/// like the git short hash and build date.
+pub fn version_meta_for(verbose_version_string: &str) -> Result<VersionMeta> {
+    let mut map = HashMap::new();
+    for (i, line) in verbose_version_string.lines().enumerate() {
+        if i == 0 {
+            map.insert("short", line);
+            continue;
+        }
+
+        let mut parts = line.splitn(2, ": ");
+        let key = match parts.next() {
+            Some(key) => key,
+            None => continue,
+        };
+
+        if let Some(value) = parts.next() {
+            map.insert(key, value);
+        }
+    }
+
+    let short_version_string = expect_key("short", &map)?;
+    let host = expect_key("host", &map)?;
+    let release = expect_key("release", &map)?;
+    let semver: Version = release.parse()?;
+
+    let channel = match semver.pre.split('.').next().unwrap() {
+        "" => Channel::Stable,
+        "dev" => Channel::Dev,
+        "beta" => Channel::Beta,
+        "nightly" => Channel::Nightly,
+        x => return Err(Error::UnknownPreReleaseTag(x.to_owned())),
+    };
+
+    let commit_hash = expect_key_or_unknown("commit-hash", &map)?;
+    let commit_date = expect_key_or_unknown("commit-date", &map)?;
+    let build_date = map
+        .get("build-date")
+        .filter(|&v| *v != "unknown")
+        .map(|&v| String::from(v));
+    let llvm_version = match map.get("LLVM version") {
+        Some(&v) => Some(v.parse()?),
+        None => None,
+    };
+
+    Ok(VersionMeta {
+        semver,
+        commit_hash,
+        commit_date,
+        build_date,
+        channel,
+        host,
+        short_version_string,
+        llvm_version,
+    })
+}
+
+fn expect_key_or_unknown(key: &str, map: &HashMap<&str, &str>) -> Result<Option<String>, Error> {
+    match map.get(key) {
+        Some(&v) if v == "unknown" => Ok(None),
+        Some(&v) => Ok(Some(String::from(v))),
+        None => Err(Error::UnexpectedVersionFormat),
+    }
+}
+
+fn expect_key(key: &str, map: &HashMap<&str, &str>) -> Result<String, Error> {
+    map.get(key)
+        .map(|&v| String::from(v))
+        .ok_or(Error::UnexpectedVersionFormat)
+}
+
+/// LLVM Version Parse Error
+#[derive(Debug)]
+pub enum LlvmVersionParseError {
+    /// An error occurred in parsing a version component as an integer
+    ParseIntError(num::ParseIntError),
+    /// A version component must not have leading zeros
+    ComponentMustNotHaveLeadingZeros,
+    /// A version component has a sign
+    ComponentMustNotHaveSign,
+    /// Minor version component must be zero on LLVM versions later than 4.0
+    MinorVersionMustBeZeroAfter4,
+    /// Minor version component is required on LLVM versions earlier than 4.0
+    MinorVersionRequiredBefore4,
+    /// Too many components
+    TooManyComponents,
+}
+
+impl From<num::ParseIntError> for LlvmVersionParseError {
+    fn from(e: num::ParseIntError) -> Self {
+        LlvmVersionParseError::ParseIntError(e)
+    }
+}
+
+impl fmt::Display for LlvmVersionParseError {
+    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+        match self {
+            LlvmVersionParseError::ParseIntError(e) => {
+                write!(f, "error parsing LLVM version component: {}", e)
+            }
+            LlvmVersionParseError::ComponentMustNotHaveLeadingZeros => {
+                write!(f, "a version component must not have leading zeros")
+            }
+            LlvmVersionParseError::ComponentMustNotHaveSign => {
+                write!(f, "a version component must not have a sign")
+            }
+            LlvmVersionParseError::MinorVersionMustBeZeroAfter4 => write!(
+                f,
+                "LLVM's minor version component must be 0 for versions greater than 4.0"
+            ),
+            LlvmVersionParseError::MinorVersionRequiredBefore4 => write!(
+                f,
+                "LLVM's minor version component is required for versions less than 4.0"
+            ),
+            LlvmVersionParseError::TooManyComponents => write!(f, "too many version components"),
+        }
+    }
+}
+
+impl error::Error for LlvmVersionParseError {
+    fn source(&self) -> Option<&(dyn error::Error + 'static)> {
+        match self {
+            LlvmVersionParseError::ParseIntError(e) => Some(e),
+            LlvmVersionParseError::ComponentMustNotHaveLeadingZeros
+            | LlvmVersionParseError::ComponentMustNotHaveSign
+            | LlvmVersionParseError::MinorVersionMustBeZeroAfter4
+            | LlvmVersionParseError::MinorVersionRequiredBefore4
+            | LlvmVersionParseError::TooManyComponents => None,
+        }
+    }
+}
+
+/// The error type for this crate.
+#[derive(Debug)]
+pub enum Error {
+    /// An error occurred while trying to find the `rustc` to run.
+    CouldNotExecuteCommand(io::Error),
+    /// Error output from the command that was run.
+    CommandError {
+        /// stdout output from the command
+        stdout: String,
+        /// stderr output from the command
+        stderr: String,
+    },
+    /// The output of `rustc -vV` was not valid utf-8.
+    Utf8Error(str::Utf8Error),
+    /// The output of `rustc -vV` was not in the expected format.
+    UnexpectedVersionFormat,
+    /// An error occurred in parsing the semver.
+    SemVerError(semver::Error),
+    /// The pre-release tag is unknown.
+    UnknownPreReleaseTag(String),
+    /// An error occurred in parsing a `LlvmVersion`.
+    LlvmVersionError(LlvmVersionParseError),
+}
+
+impl fmt::Display for Error {
+    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+        match *self {
+            CouldNotExecuteCommand(ref e) => write!(f, "could not execute command: {}", e),
+            CommandError {
+                ref stdout,
+                ref stderr,
+            } => write!(
+                f,
+                "error from command -- stderr:\n\n{}\n\nstderr:\n\n{}",
+                stderr, stdout,
+            ),
+            Utf8Error(_) => write!(f, "invalid UTF-8 output from `rustc -vV`"),
+            UnexpectedVersionFormat => write!(f, "unexpected `rustc -vV` format"),
+            SemVerError(ref e) => write!(f, "error parsing version: {}", e),
+            UnknownPreReleaseTag(ref i) => write!(f, "unknown pre-release tag: {}", i),
+            LlvmVersionError(ref e) => write!(f, "error parsing LLVM's version: {}", e),
+        }
+    }
+}
+
+impl error::Error for Error {
+    fn source(&self) -> Option<&(dyn error::Error + 'static)> {
+        match *self {
+            CouldNotExecuteCommand(ref e) => Some(e),
+            CommandError { .. } => None,
+            Utf8Error(ref e) => Some(e),
+            UnexpectedVersionFormat => None,
+            SemVerError(ref e) => Some(e),
+            UnknownPreReleaseTag(_) => None,
+            LlvmVersionError(ref e) => Some(e),
+        }
+    }
+}
+
+macro_rules! impl_from {
+    ($($err_ty:ty => $variant:ident),* $(,)*) => {
+        $(
+            impl From<$err_ty> for Error {
+                fn from(e: $err_ty) -> Error {
+                    Error::$variant(e)
+                }
+            }
+        )*
+    }
+}
+
+impl_from! {
+    str::Utf8Error => Utf8Error,
+    semver::Error => SemVerError,
+    LlvmVersionParseError => LlvmVersionError,
+}
+
+/// The result type for this crate.
+pub type Result<T, E = Error> = std::result::Result<T, E>;
diff --git a/tests/all.rs b/tests/all.rs
new file mode 100644
index 0000000..c3cff70
--- /dev/null
+++ b/tests/all.rs
@@ -0,0 +1,456 @@
+#![allow(clippy::match_like_matches_macro)]
+
+use std::process::Command;
+
+use rustc_version::{
+    version, version_meta, version_meta_for, Channel, Error, LlvmVersion, LlvmVersionParseError,
+    Version, VersionMeta,
+};
+
+#[test]
+fn rustc_error() {
+    let mut cmd = Command::new("rustc");
+    cmd.arg("--FOO");
+    let stderr = match VersionMeta::for_command(cmd) {
+        Err(Error::CommandError { stdout: _, stderr }) => stderr,
+        _ => panic!("command error expected"),
+    };
+    assert_eq!(stderr, "error: Unrecognized option: \'FOO\'\n\n");
+}
+
+#[test]
+fn smoketest() {
+    let v = version().unwrap();
+    assert!(v.major >= 1);
+
+    let v = version_meta().unwrap();
+    assert!(v.semver.major >= 1);
+
+    assert!(version().unwrap() >= Version::parse("1.0.0").unwrap());
+}
+
+#[test]
+fn parse_1_0_0() {
+    let version = version_meta_for(
+        "rustc 1.0.0 (a59de37e9 2015-05-13) (built 2015-05-14)
+binary: rustc
+commit-hash: a59de37e99060162a2674e3ff45409ac73595c0e
+commit-date: 2015-05-13
+build-date: 2015-05-14
+host: x86_64-unknown-linux-gnu
+release: 1.0.0",
+    )
+    .unwrap();
+
+    assert_eq!(version.semver, Version::parse("1.0.0").unwrap());
+    assert_eq!(
+        version.commit_hash,
+        Some("a59de37e99060162a2674e3ff45409ac73595c0e".into())
+    );
+    assert_eq!(version.commit_date, Some("2015-05-13".into()));
+    assert_eq!(version.build_date, Some("2015-05-14".into()));
+    assert_eq!(version.channel, Channel::Stable);
+    assert_eq!(version.host, "x86_64-unknown-linux-gnu");
+    assert_eq!(
+        version.short_version_string,
+        "rustc 1.0.0 (a59de37e9 2015-05-13) (built 2015-05-14)"
+    );
+    assert_eq!(version.llvm_version, None);
+}
+
+#[test]
+fn parse_unknown() {
+    let version = version_meta_for(
+        "rustc 1.3.0
+binary: rustc
+commit-hash: unknown
+commit-date: unknown
+host: x86_64-unknown-linux-gnu
+release: 1.3.0",
+    )
+    .unwrap();
+
+    assert_eq!(version.semver, Version::parse("1.3.0").unwrap());
+    assert_eq!(version.commit_hash, None);
+    assert_eq!(version.commit_date, None);
+    assert_eq!(version.channel, Channel::Stable);
+    assert_eq!(version.host, "x86_64-unknown-linux-gnu");
+    assert_eq!(version.short_version_string, "rustc 1.3.0");
+    assert_eq!(version.llvm_version, None);
+}
+
+#[test]
+fn parse_nightly() {
+    let version = version_meta_for(
+        "rustc 1.5.0-nightly (65d5c0833 2015-09-29)
+binary: rustc
+commit-hash: 65d5c083377645a115c4ac23a620d3581b9562b6
+commit-date: 2015-09-29
+host: x86_64-unknown-linux-gnu
+release: 1.5.0-nightly",
+    )
+    .unwrap();
+
+    assert_eq!(version.semver, Version::parse("1.5.0-nightly").unwrap());
+    assert_eq!(
+        version.commit_hash,
+        Some("65d5c083377645a115c4ac23a620d3581b9562b6".into())
+    );
+    assert_eq!(version.commit_date, Some("2015-09-29".into()));
+    assert_eq!(version.channel, Channel::Nightly);
+    assert_eq!(version.host, "x86_64-unknown-linux-gnu");
+    assert_eq!(
+        version.short_version_string,
+        "rustc 1.5.0-nightly (65d5c0833 2015-09-29)"
+    );
+    assert_eq!(version.llvm_version, None);
+}
+
+#[test]
+fn parse_stable() {
+    let version = version_meta_for(
+        "rustc 1.3.0 (9a92aaf19 2015-09-15)
+binary: rustc
+commit-hash: 9a92aaf19a64603b02b4130fe52958cc12488900
+commit-date: 2015-09-15
+host: x86_64-unknown-linux-gnu
+release: 1.3.0",
+    )
+    .unwrap();
+
+    assert_eq!(version.semver, Version::parse("1.3.0").unwrap());
+    assert_eq!(
+        version.commit_hash,
+        Some("9a92aaf19a64603b02b4130fe52958cc12488900".into())
+    );
+    assert_eq!(version.commit_date, Some("2015-09-15".into()));
+    assert_eq!(version.channel, Channel::Stable);
+    assert_eq!(version.host, "x86_64-unknown-linux-gnu");
+    assert_eq!(
+        version.short_version_string,
+        "rustc 1.3.0 (9a92aaf19 2015-09-15)"
+    );
+    assert_eq!(version.llvm_version, None);
+}
+
+#[test]
+fn parse_1_16_0_nightly() {
+    let version = version_meta_for(
+        "rustc 1.16.0-nightly (5d994d8b7 2017-01-05)
+binary: rustc
+commit-hash: 5d994d8b7e482e87467d4a521911477bd8284ce3
+commit-date: 2017-01-05
+host: x86_64-unknown-linux-gnu
+release: 1.16.0-nightly
+LLVM version: 3.9",
+    )
+    .unwrap();
+
+    assert_eq!(version.semver, Version::parse("1.16.0-nightly").unwrap());
+    assert_eq!(
+        version.commit_hash,
+        Some("5d994d8b7e482e87467d4a521911477bd8284ce3".into())
+    );
+    assert_eq!(version.commit_date, Some("2017-01-05".into()));
+    assert_eq!(version.channel, Channel::Nightly);
+    assert_eq!(version.host, "x86_64-unknown-linux-gnu");
+    assert_eq!(
+        version.short_version_string,
+        "rustc 1.16.0-nightly (5d994d8b7 2017-01-05)"
+    );
+    assert_eq!(
+        version.llvm_version,
+        Some(LlvmVersion { major: 3, minor: 9 })
+    );
+}
+
+#[test]
+fn parse_1_47_0_stable() {
+    let version = version_meta_for(
+        "rustc 1.47.0 (18bf6b4f0 2020-10-07)
+binary: rustc
+commit-hash: 18bf6b4f01a6feaf7259ba7cdae58031af1b7b39
+commit-date: 2020-10-07
+host: powerpc64le-unknown-linux-gnu
+release: 1.47.0
+LLVM version: 11.0",
+    )
+    .unwrap();
+
+    assert_eq!(version.semver, Version::parse("1.47.0").unwrap());
+    assert_eq!(
+        version.commit_hash,
+        Some("18bf6b4f01a6feaf7259ba7cdae58031af1b7b39".into())
+    );
+    assert_eq!(version.commit_date, Some("2020-10-07".into()));
+    assert_eq!(version.channel, Channel::Stable);
+    assert_eq!(version.host, "powerpc64le-unknown-linux-gnu");
+    assert_eq!(
+        version.short_version_string,
+        "rustc 1.47.0 (18bf6b4f0 2020-10-07)"
+    );
+    assert_eq!(
+        version.llvm_version,
+        Some(LlvmVersion {
+            major: 11,
+            minor: 0,
+        })
+    );
+}
+
+#[test]
+fn parse_llvm_micro() {
+    let version = version_meta_for(
+        "rustc 1.51.0-nightly (4253153db 2021-01-17)
+binary: rustc
+commit-hash: 4253153db205251f72ea4493687a31e04a2a8ca0
+commit-date: 2021-01-17
+host: x86_64-pc-windows-msvc
+release: 1.51.0-nightly
+LLVM version: 11.0.1",
+    )
+    .unwrap();
+
+    assert_eq!(version.semver, Version::parse("1.51.0-nightly").unwrap());
+    assert_eq!(
+        version.commit_hash.unwrap(),
+        "4253153db205251f72ea4493687a31e04a2a8ca0"
+    );
+    assert_eq!(version.commit_date.unwrap(), "2021-01-17");
+    assert_eq!(version.host, "x86_64-pc-windows-msvc");
+    assert_eq!(
+        version.short_version_string,
+        "rustc 1.51.0-nightly (4253153db 2021-01-17)"
+    );
+    assert_eq!(
+        version.llvm_version,
+        Some(LlvmVersion {
+            major: 11,
+            minor: 0
+        })
+    );
+}
+
+#[test]
+fn parse_debian_buster() {
+    let version = version_meta_for(
+        "rustc 1.41.1
+binary: rustc
+commit-hash: unknown
+commit-date: unknown
+host: powerpc64le-unknown-linux-gnu
+release: 1.41.1
+LLVM version: 7.0",
+    )
+    .unwrap();
+
+    assert_eq!(version.semver, Version::parse("1.41.1").unwrap());
+    assert_eq!(version.commit_hash, None);
+    assert_eq!(version.commit_date, None);
+    assert_eq!(version.channel, Channel::Stable);
+    assert_eq!(version.host, "powerpc64le-unknown-linux-gnu");
+    assert_eq!(version.short_version_string, "rustc 1.41.1");
+    assert_eq!(
+        version.llvm_version,
+        Some(LlvmVersion { major: 7, minor: 0 })
+    );
+}
+
+#[test]
+fn parse_termux() {
+    let version = version_meta_for(
+        "rustc 1.46.0
+binary: rustc
+commit-hash: unknown
+commit-date: unknown
+host: aarch64-linux-android
+release: 1.46.0
+LLVM version: 10.0",
+    )
+    .unwrap();
+
+    assert_eq!(version.semver, Version::parse("1.46.0").unwrap());
+    assert_eq!(version.commit_hash, None);
+    assert_eq!(version.commit_date, None);
+    assert_eq!(version.channel, Channel::Stable);
+    assert_eq!(version.host, "aarch64-linux-android");
+    assert_eq!(version.short_version_string, "rustc 1.46.0");
+    assert_eq!(
+        version.llvm_version,
+        Some(LlvmVersion {
+            major: 10,
+            minor: 0,
+        })
+    );
+}
+
+#[test]
+fn parse_llvm_version_empty() {
+    let res: Result<LlvmVersion, _> = "".parse();
+    assert!(match res {
+        Err(LlvmVersionParseError::ParseIntError(_)) => true,
+        _ => false,
+    });
+}
+
+#[test]
+fn parse_llvm_version_invalid_char() {
+    let res: Result<LlvmVersion, _> = "A".parse();
+    assert!(match res {
+        Err(LlvmVersionParseError::ParseIntError(_)) => true,
+        _ => false,
+    });
+}
+
+#[test]
+fn parse_llvm_version_overflow() {
+    let res: Result<LlvmVersion, _> = "9999999999999999999999999999999".parse();
+    assert!(match res {
+        Err(LlvmVersionParseError::ParseIntError(_)) => true,
+        _ => false,
+    });
+}
+
+#[test]
+fn parse_llvm_version_leading_zero_on_zero() {
+    let res: Result<LlvmVersion, _> = "00".parse();
+    assert!(match res {
+        Err(LlvmVersionParseError::ComponentMustNotHaveLeadingZeros) => true,
+        _ => false,
+    });
+}
+
+#[test]
+fn parse_llvm_version_leading_zero_on_nonzero() {
+    let res: Result<LlvmVersion, _> = "01".parse();
+    assert!(match res {
+        Err(LlvmVersionParseError::ComponentMustNotHaveLeadingZeros) => true,
+        _ => false,
+    });
+}
+
+#[test]
+fn parse_llvm_version_4_components() {
+    let res: Result<LlvmVersion, _> = "4.0.0.0".parse();
+
+    assert!(match res {
+        Err(LlvmVersionParseError::TooManyComponents) => true,
+        _ => false,
+    });
+}
+
+#[test]
+fn parse_llvm_version_component_sign_plus() {
+    let res: Result<LlvmVersion, _> = "1.+3".parse();
+
+    assert!(match res {
+        Err(LlvmVersionParseError::ComponentMustNotHaveSign) => true,
+        _ => false,
+    });
+}
+
+#[test]
+fn parse_llvm_version_component_sign_minus() {
+    let res: Result<LlvmVersion, _> = "1.-3".parse();
+
+    assert!(match res {
+        Err(LlvmVersionParseError::ComponentMustNotHaveSign) => true,
+        _ => false,
+    });
+}
+
+#[test]
+fn parse_llvm_version_3() {
+    let res: Result<LlvmVersion, _> = "3".parse();
+
+    assert!(match res {
+        Err(LlvmVersionParseError::MinorVersionRequiredBefore4) => true,
+        _ => false,
+    });
+}
+
+#[test]
+fn parse_llvm_version_5() {
+    let v: LlvmVersion = "5".parse().unwrap();
+    assert_eq!(v, LlvmVersion { major: 5, minor: 0 });
+}
+
+#[test]
+fn parse_llvm_version_5_0() {
+    let v: LlvmVersion = "5.0".parse().unwrap();
+    assert_eq!(v, LlvmVersion { major: 5, minor: 0 });
+}
+
+#[test]
+fn parse_llvm_version_4_0() {
+    let v: LlvmVersion = "4.0".parse().unwrap();
+    assert_eq!(v, LlvmVersion { major: 4, minor: 0 });
+}
+
+#[test]
+fn parse_llvm_version_3_0() {
+    let v: LlvmVersion = "3.0".parse().unwrap();
+    assert_eq!(v, LlvmVersion { major: 3, minor: 0 });
+}
+
+#[test]
+fn parse_llvm_version_3_9() {
+    let v: LlvmVersion = "3.9".parse().unwrap();
+    assert_eq!(v, LlvmVersion { major: 3, minor: 9 });
+}
+
+#[test]
+fn parse_llvm_version_11_0() {
+    let v: LlvmVersion = "11.0".parse().unwrap();
+    assert_eq!(
+        v,
+        LlvmVersion {
+            major: 11,
+            minor: 0
+        }
+    );
+}
+
+#[test]
+fn parse_llvm_version_11() {
+    let v: LlvmVersion = "11".parse().unwrap();
+    assert_eq!(
+        v,
+        LlvmVersion {
+            major: 11,
+            minor: 0
+        }
+    );
+}
+
+#[test]
+fn test_llvm_version_comparison() {
+    // check that field order is correct
+    assert!(LlvmVersion { major: 3, minor: 9 } < LlvmVersion { major: 4, minor: 0 });
+}
+
+/*
+#[test]
+fn version_matches_replacement() {
+    let f = |s1: &str, s2: &str| {
+        let a = Version::parse(s1).unwrap();
+        let b = Version::parse(s2).unwrap();
+        println!("{} <= {} : {}", s1, s2, a <= b);
+    };
+
+    println!();
+
+    f("1.5.0",         "1.5.0");
+    f("1.5.0-nightly", "1.5.0");
+    f("1.5.0",         "1.5.0-nightly");
+    f("1.5.0-nightly", "1.5.0-nightly");
+
+    f("1.5.0",         "1.6.0");
+    f("1.5.0-nightly", "1.6.0");
+    f("1.5.0",         "1.6.0-nightly");
+    f("1.5.0-nightly", "1.6.0-nightly");
+
+    panic!();
+
+}
+*/