Import assert_matches 1.5.0upstream/1.5.0upstream

11 files changed, 691 insertions, 0 deletions

diff --git a/.cargo_vcs_info.json b/.cargo_vcs_info.json
new file mode 100644
index 0000000..3b4dce7
--- /dev/null
+++ b/.cargo_vcs_info.json
@@ -0,0 +1,5 @@
+{
+  "git": {
+    "sha1": "969a37d5ad1d2a9060839ada3e400c4d6483f877"
+  }
+}
diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
new file mode 100644
index 0000000..759266a
--- /dev/null
+++ b/.github/workflows/ci.yml
@@ -0,0 +1,33 @@
+name: CI
+
+on:
+  pull_request:
+    paths:
+      - '**.rs'
+      - '**.toml'
+      - '.github/workflows/ci.yml'
+  push:
+    branches: [master]
+    paths:
+      - '**.rs'
+      - '**.toml'
+      - '.github/workflows/ci.yml'
+
+jobs:
+  Test:
+    runs-on: ubuntu-latest
+
+    steps:
+    - uses: actions/checkout@v1
+    - uses: hecrj/setup-rust-action@v1
+
+    - name: Build
+      run: cargo build --verbose
+
+    - name: Test
+      run: cargo test --verbose
+
+    env:
+      RUST_BACKTRACE: 1
+      RUST_INCREMENTAL: 0
+      RUSTFLAGS: "-C debuginfo=0"
diff --git a/.gitignore b/.gitignore
new file mode 100644
index 0000000..a9d37c5
--- /dev/null
+++ b/.gitignore
@@ -0,0 +1,2 @@
+target
+Cargo.lock
diff --git a/Cargo.toml b/Cargo.toml
new file mode 100644
index 0000000..e5352cc
--- /dev/null
+++ b/Cargo.toml
@@ -0,0 +1,24 @@
+# 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]
+name = "assert_matches"
+version = "1.5.0"
+authors = ["Murarth <murarth@gmail.com>"]
+description = "Asserts that a value matches a pattern"
+homepage = "https://github.com/murarth/assert_matches"
+documentation = "https://docs.rs/assert_matches/"
+readme = "README.md"
+keywords = ["assert", "match", "pattern"]
+categories = ["no-std"]
+license = "MIT/Apache-2.0"
+repository = "https://github.com/murarth/assert_matches"
diff --git a/Cargo.toml.orig b/Cargo.toml.orig
new file mode 100644
index 0000000..3436c8c
--- /dev/null
+++ b/Cargo.toml.orig
@@ -0,0 +1,15 @@
+[package]
+name = "assert_matches"
+description = "Asserts that a value matches a pattern"
+
+version = "1.5.0"
+authors = ["Murarth <murarth@gmail.com>"]
+
+documentation = "https://docs.rs/assert_matches/"
+homepage = "https://github.com/murarth/assert_matches"
+repository = "https://github.com/murarth/assert_matches"
+
+keywords = ["assert", "match", "pattern"]
+categories = ["no-std"]
+license = "MIT/Apache-2.0"
+readme = "README.md"
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..3d71368
--- /dev/null
+++ b/LICENSE-MIT
@@ -0,0 +1,25 @@
+Copyright (c) 2016 Murarth
+
+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
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+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..bceba4e
--- /dev/null
+++ b/README.md
@@ -0,0 +1,44 @@
+# assert_matches
+
+Provides a macro, `assert_matches`, which tests whether a value
+matches a given pattern, causing a panic if the match fails.
+
+[Documentation](https://docs.rs/assert_matches/)
+
+```rust
+#[macro_use] extern crate assert_matches;
+
+#[derive(Debug)]
+enum Foo {
+    A(i32),
+    B(i32),
+}
+
+let a = Foo::A(1);
+
+assert_matches!(a, Foo::A(_));
+
+assert_matches!(a, Foo::A(i) if i > 0);
+```
+
+To include in your project, only when tests are compiled, add the following
+to your Cargo.toml:
+
+```toml
+[dev-dependencies]
+assert_matches = "1.5"
+```
+
+And add the following to your crate root:
+
+```rust
+#[cfg(test)] #[macro_use]
+extern crate assert_matches;
+```
+
+## License
+
+`assert_matches` is distributed under the terms of both the MIT license and the
+Apache License (Version 2.0).
+
+See LICENSE-APACHE and LICENSE-MIT for details.
diff --git a/src/lib.rs b/src/lib.rs
new file mode 100644
index 0000000..5a61329
--- /dev/null
+++ b/src/lib.rs
@@ -0,0 +1,324 @@
+//! Provides a macro, `assert_matches!`, which tests whether a value
+//! matches a given pattern, causing a panic if the match fails.
+//!
+//! See the macro [`assert_matches!`] documentation for more information.
+//!
+//! Also provides a debug-only counterpart, [`debug_assert_matches!`].
+//!
+//! See the macro [`debug_assert_matches!`] documentation for more information
+//! about this macro.
+//!
+//! [`assert_matches!`]: macro.assert_matches.html
+//! [`debug_assert_matches!`]: macro.debug_assert_matches.html
+
+#![deny(missing_docs)]
+#![cfg_attr(not(test), no_std)]
+
+/// Asserts that an expression matches a given pattern.
+///
+/// A guard expression may be supplied to add further restrictions to the
+/// expected value of the expression.
+///
+/// A `match` arm may be supplied to perform additional assertions or to yield
+/// a value from the macro invocation.
+///
+/// # Examples
+///
+/// ```
+/// #[macro_use] extern crate assert_matches;
+///
+/// #[derive(Debug)]
+/// enum Foo {
+///     A(i32),
+///     B(&'static str),
+/// }
+///
+/// # fn main() {
+/// let a = Foo::A(1);
+///
+/// // Assert that `a` matches the pattern `Foo::A(_)`.
+/// assert_matches!(a, Foo::A(_));
+///
+/// // Assert that `a` matches the pattern and
+/// // that the contained value meets the condition `i > 0`.
+/// assert_matches!(a, Foo::A(i) if i > 0);
+///
+/// let b = Foo::B("foobar");
+/// 
+/// // Assert that `b` matches the pattern `Foo::B(_)`.
+/// assert_matches!(b, Foo::B(s) => {
+///     // Perform additional assertions on the variable binding `s`.
+///     assert!(s.starts_with("foo"));
+///     assert!(s.ends_with("bar"));
+/// });
+///
+/// // Assert that `b` matches the pattern and yield the string `s`.
+/// let s = assert_matches!(b, Foo::B(s) => s);
+///
+/// // Perform an assertion on the value `s`.
+/// assert_eq!(s, "foobar");
+/// # }
+/// ```
+#[macro_export]
+macro_rules! assert_matches {
+    ( $e:expr , $($pat:pat)|+ ) => {
+        match $e {
+            $($pat)|+ => (),
+            ref e => panic!("assertion failed: `{:?}` does not match `{}`",
+                e, stringify!($($pat)|+))
+        }
+    };
+    ( $e:expr , $($pat:pat)|+ if $cond:expr ) => {
+        match $e {
+            $($pat)|+ if $cond => (),
+            ref e => panic!("assertion failed: `{:?}` does not match `{}`",
+                e, stringify!($($pat)|+ if $cond))
+        }
+    };
+    ( $e:expr , $($pat:pat)|+ => $arm:expr ) => {
+        match $e {
+            $($pat)|+ => $arm,
+            ref e => panic!("assertion failed: `{:?}` does not match `{}`",
+                e, stringify!($($pat)|+))
+        }
+    };
+    ( $e:expr , $($pat:pat)|+ if $cond:expr => $arm:expr ) => {
+        match $e {
+            $($pat)|+ if $cond => $arm,
+            ref e => panic!("assertion failed: `{:?}` does not match `{}`",
+                e, stringify!($($pat)|+ if $cond))
+        }
+    };
+    ( $e:expr , $($pat:pat)|+ , $($arg:tt)* ) => {
+        match $e {
+            $($pat)|+ => (),
+            ref e => panic!("assertion failed: `{:?}` does not match `{}`: {}",
+                e, stringify!($($pat)|+), format_args!($($arg)*))
+        }
+    };
+    ( $e:expr , $($pat:pat)|+ if $cond:expr , $($arg:tt)* ) => {
+        match $e {
+            $($pat)|+ if $cond => (),
+            ref e => panic!("assertion failed: `{:?}` does not match `{}`: {}",
+                e, stringify!($($pat)|+ if $cond), format_args!($($arg)*))
+        }
+    };
+    ( $e:expr , $($pat:pat)|+ => $arm:expr , $($arg:tt)* ) => {
+        match $e {
+            $($pat)|+ => $arm,
+            ref e => panic!("assertion failed: `{:?}` does not match `{}`: {}",
+                e, stringify!($($pat)|+), format_args!($($arg)*))
+        }
+    };
+    ( $e:expr , $($pat:pat)|+ if $cond:expr => $arm:expr , $($arg:tt)* ) => {
+        match $e {
+            $($pat)|+ if $cond => $arm,
+            ref e => panic!("assertion failed: `{:?}` does not match `{}`: {}",
+                e, stringify!($($pat)|+ if $cond), format_args!($($arg)*))
+        }
+    };
+}
+
+/// Asserts that an expression matches a given pattern.
+///
+/// Unlike [`assert_matches!`], `debug_assert_matches!` statements are only enabled
+/// in non-optimized builds by default. An optimized build will omit all
+/// `debug_assert_matches!` statements unless `-C debug-assertions` is passed
+/// to the compiler.
+///
+/// See the macro [`assert_matches!`] documentation for more information.
+///
+/// [`assert_matches!`]: macro.assert_matches.html
+#[macro_export(local_inner_macros)]
+macro_rules! debug_assert_matches {
+    ( $($tt:tt)* ) => { {
+        if _assert_matches_cfg!(debug_assertions) {
+            assert_matches!($($tt)*);
+        }
+    } }
+}
+
+#[doc(hidden)]
+#[macro_export]
+macro_rules! _assert_matches_cfg {
+    ( $($tt:tt)* ) => { cfg!($($tt)*) }
+}
+
+#[cfg(test)]
+mod test {
+    use std::panic::{catch_unwind, UnwindSafe};
+
+    #[derive(Debug)]
+    enum Foo {
+        A(i32),
+        B(&'static str),
+        C(&'static str),
+    }
+
+    #[test]
+    fn test_assert_succeed() {
+        let a = Foo::A(123);
+
+        assert_matches!(a, Foo::A(_));
+        assert_matches!(a, Foo::A(123));
+        assert_matches!(a, Foo::A(i) if i == 123);
+        assert_matches!(a, Foo::A(42) | Foo::A(123));
+
+        let b = Foo::B("foo");
+
+        assert_matches!(b, Foo::B(_));
+        assert_matches!(b, Foo::B("foo"));
+        assert_matches!(b, Foo::B(s) if s == "foo");
+        assert_matches!(b, Foo::B(s) => assert_eq!(s, "foo"));
+        assert_matches!(b, Foo::B(s) => { assert_eq!(s, "foo"); assert!(true) });
+        assert_matches!(b, Foo::B(s) if s == "foo" => assert_eq!(s, "foo"));
+        assert_matches!(b, Foo::B(s) if s == "foo" => { assert_eq!(s, "foo"); assert!(true) });
+
+        let c = Foo::C("foo");
+
+        assert_matches!(c, Foo::B(_) | Foo::C(_));
+        assert_matches!(c, Foo::B("foo") | Foo::C("foo"));
+        assert_matches!(c, Foo::B(s) | Foo::C(s) if s == "foo");
+        assert_matches!(c, Foo::B(s) | Foo::C(s) => assert_eq!(s, "foo"));
+        assert_matches!(c, Foo::B(s) | Foo::C(s) => { assert_eq!(s, "foo"); assert!(true) });
+        assert_matches!(c, Foo::B(s) | Foo::C(s) if s == "foo" => assert_eq!(s, "foo"));
+        assert_matches!(c, Foo::B(s) | Foo::C(s) if s == "foo" => { assert_eq!(s, "foo"); assert!(true) });
+    }
+
+    #[test]
+    #[should_panic]
+    fn test_assert_panic_0() {
+        let a = Foo::A(123);
+
+        assert_matches!(a, Foo::B(_));
+    }
+
+    #[test]
+    #[should_panic]
+    fn test_assert_panic_1() {
+        let b = Foo::B("foo");
+
+        assert_matches!(b, Foo::B("bar"));
+    }
+
+    #[test]
+    #[should_panic]
+    fn test_assert_panic_2() {
+        let b = Foo::B("foo");
+
+        assert_matches!(b, Foo::B(s) if s == "bar");
+    }
+
+    #[test]
+    #[should_panic]
+    fn test_assert_panic_3() {
+        let b = Foo::B("foo");
+
+        assert_matches!(b, Foo::B(s) => assert_eq!(s, "bar"));
+    }
+
+    #[test]
+    #[should_panic]
+    fn test_assert_panic_4() {
+        let b = Foo::B("foo");
+
+        assert_matches!(b, Foo::B(s) if s == "bar" => assert_eq!(s, "foo"));
+    }
+
+    #[test]
+    #[should_panic]
+    fn test_assert_panic_5() {
+        let b = Foo::B("foo");
+
+        assert_matches!(b, Foo::B(s) if s == "foo" => assert_eq!(s, "bar"));
+    }
+
+    #[test]
+    #[should_panic]
+    fn test_assert_panic_6() {
+        let b = Foo::B("foo");
+
+        assert_matches!(b, Foo::B(s) if s == "foo" => { assert_eq!(s, "foo"); assert!(false) });
+    }
+
+    #[test]
+    fn test_assert_no_move() {
+        let b = &mut Foo::A(0);
+        assert_matches!(*b, Foo::A(0));
+    }
+
+    #[test]
+    fn assert_with_message() {
+        let a = Foo::A(0);
+
+        assert_matches!(a, Foo::A(_), "o noes");
+        assert_matches!(a, Foo::A(n) if n == 0, "o noes");
+        assert_matches!(a, Foo::A(n) => assert_eq!(n, 0), "o noes");
+        assert_matches!(a, Foo::A(n) => { assert_eq!(n, 0); assert!(n < 1) }, "o noes");
+        assert_matches!(a, Foo::A(n) if n == 0 => assert_eq!(n, 0), "o noes");
+        assert_matches!(a, Foo::A(n) if n == 0 => { assert_eq!(n, 0); assert!(n < 1) }, "o noes");
+        assert_matches!(a, Foo::A(_), "o noes {:?}", a);
+        assert_matches!(a, Foo::A(n) if n == 0, "o noes {:?}", a);
+        assert_matches!(a, Foo::A(n) => assert_eq!(n, 0), "o noes {:?}", a);
+        assert_matches!(a, Foo::A(n) => { assert_eq!(n, 0); assert!(n < 1) }, "o noes {:?}", a);
+        assert_matches!(a, Foo::A(_), "o noes {value:?}", value=a);
+        assert_matches!(a, Foo::A(n) if n == 0, "o noes {value:?}", value=a);
+        assert_matches!(a, Foo::A(n) => assert_eq!(n, 0), "o noes {value:?}", value=a);
+        assert_matches!(a, Foo::A(n) => { assert_eq!(n, 0); assert!(n < 1) }, "o noes {value:?}", value=a);
+        assert_matches!(a, Foo::A(n) if n == 0 => assert_eq!(n, 0), "o noes {value:?}", value=a);
+    }
+
+    fn panic_message<F>(f: F) -> String
+            where F: FnOnce() + UnwindSafe {
+        let err = catch_unwind(f)
+            .expect_err("function did not panic");
+
+        *err.downcast::<String>()
+            .expect("function panicked with non-String value")
+    }
+
+    #[test]
+    fn test_panic_message() {
+        let a = Foo::A(1);
+
+        // expr, pat
+        assert_eq!(panic_message(|| {
+            assert_matches!(a, Foo::B(_));
+        }), r#"assertion failed: `A(1)` does not match `Foo::B(_)`"#);
+
+        // expr, pat if cond
+        assert_eq!(panic_message(|| {
+            assert_matches!(a, Foo::B(s) if s == "foo");
+        }), r#"assertion failed: `A(1)` does not match `Foo::B(s) if s == "foo"`"#);
+
+        // expr, pat => arm
+        assert_eq!(panic_message(|| {
+            assert_matches!(a, Foo::B(_) => {});
+        }), r#"assertion failed: `A(1)` does not match `Foo::B(_)`"#);
+
+        // expr, pat if cond => arm
+        assert_eq!(panic_message(|| {
+            assert_matches!(a, Foo::B(s) if s == "foo" => {});
+        }), r#"assertion failed: `A(1)` does not match `Foo::B(s) if s == "foo"`"#);
+
+        // expr, pat, args
+        assert_eq!(panic_message(|| {
+            assert_matches!(a, Foo::B(_), "msg");
+        }), r#"assertion failed: `A(1)` does not match `Foo::B(_)`: msg"#);
+
+        // expr, pat if cond, args
+        assert_eq!(panic_message(|| {
+            assert_matches!(a, Foo::B(s) if s == "foo", "msg");
+        }), r#"assertion failed: `A(1)` does not match `Foo::B(s) if s == "foo"`: msg"#);
+
+        // expr, pat => arm, args
+        assert_eq!(panic_message(|| {
+            assert_matches!(a, Foo::B(_) => {}, "msg");
+        }), r#"assertion failed: `A(1)` does not match `Foo::B(_)`: msg"#);
+
+        // expr, pat if cond => arm, args
+        assert_eq!(panic_message(|| {
+            assert_matches!(a, Foo::B(s) if s == "foo" => {}, "msg");
+        }), r#"assertion failed: `A(1)` does not match `Foo::B(s) if s == "foo"`: msg"#);
+    }
+}
diff --git a/tests/selective_import1.rs b/tests/selective_import1.rs
new file mode 100644
index 0000000..7d8f8b4
--- /dev/null
+++ b/tests/selective_import1.rs
@@ -0,0 +1,9 @@
+#[macro_use(assert_matches)]
+extern crate assert_matches;
+
+#[test]
+fn test_assert_succeed() {
+    let a = 42u32;
+
+    assert_matches!(a, 42);
+}
diff --git a/tests/selective_import2.rs b/tests/selective_import2.rs
new file mode 100644
index 0000000..b983e35
--- /dev/null
+++ b/tests/selective_import2.rs
@@ -0,0 +1,9 @@
+#[macro_use(debug_assert_matches)]
+extern crate assert_matches;
+
+#[test]
+fn test_assert_succeed() {
+    let a = 42u32;
+
+    debug_assert_matches!(a, 42);
+}