Bug 1471096 - Vendor rustc_version. r=froydnj
authorMike Hommey <mh+mozilla@glandium.org>
Tue, 26 Jun 2018 10:00:26 +0900
changeset 423777 daca982d64132d8d798b8e17881da51523e18729
parent 423776 ded85684155377e4ac405fca8d01f61ae150dd0d
child 423778 909312d0fc69e078cd26c545df63067baada1816
push id34192
push userdluca@mozilla.com
push dateWed, 27 Jun 2018 10:24:39 +0000
treeherdermozilla-central@9da8a5d80b98 [default view] [failures only]
perfherder[talos] [build metrics] [platform microbench] (compared to previous push)
reviewersfroydnj
bugs1471096
milestone63.0a1
first release with
nightly linux32
nightly linux64
nightly mac
nightly win32
nightly win64
last release without
nightly linux32
nightly linux64
nightly mac
nightly win32
nightly win64
Bug 1471096 - Vendor rustc_version. r=froydnj
Cargo.lock
third_party/rust/rustc_version/.cargo-checksum.json
third_party/rust/rustc_version/.travis.yml
third_party/rust/rustc_version/Cargo.toml
third_party/rust/rustc_version/LICENSE-APACHE
third_party/rust/rustc_version/LICENSE-MIT
third_party/rust/rustc_version/README.md
third_party/rust/rustc_version/src/errors.rs
third_party/rust/rustc_version/src/lib.rs
toolkit/library/rust/shared/Cargo.toml
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -851,16 +851,17 @@ dependencies = [
  "log 0.4.2 (registry+https://github.com/rust-lang/crates.io-index)",
  "mozurl 0.0.1",
  "mp4parse_capi 0.10.1",
  "netwerk_helper 0.0.1",
  "nserror 0.1.0",
  "nsstring 0.1.0",
  "prefs_parser 0.0.1",
  "rsdparsa_capi 0.1.0",
+ "rustc_version 0.2.1 (registry+https://github.com/rust-lang/crates.io-index)",
  "u2fhid 0.2.0",
  "webrender_bindings 0.1.0",
  "xpcom 0.1.0",
 ]
 
 [[package]]
 name = "gl_generator"
 version = "0.9.0"
@@ -1756,16 +1757,24 @@ version = "0.10.3"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 
 [[package]]
 name = "rustc-serialize"
 version = "0.3.24"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 
 [[package]]
+name = "rustc_version"
+version = "0.2.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+dependencies = [
+ "semver 0.6.0 (registry+https://github.com/rust-lang/crates.io-index)",
+]
+
+[[package]]
 name = "safemem"
 version = "0.2.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 
 [[package]]
 name = "same-file"
 version = "1.0.2"
 source = "registry+https://github.com/rust-lang/crates.io-index"
@@ -2678,16 +2687,17 @@ dependencies = [
 "checksum regex 0.2.2 (registry+https://github.com/rust-lang/crates.io-index)" = "1731164734096285ec2a5ec7fea5248ae2f5485b3feeb0115af4fda2183b2d1b"
 "checksum regex 1.0.0 (registry+https://github.com/rust-lang/crates.io-index)" = "75ecf88252dce580404a22444fc7d626c01815debba56a7f4f536772a5ff19d3"
 "checksum regex-syntax 0.4.1 (registry+https://github.com/rust-lang/crates.io-index)" = "ad890a5eef7953f55427c50575c680c42841653abd2b028b68cd223d157f62db"
 "checksum regex-syntax 0.6.0 (registry+https://github.com/rust-lang/crates.io-index)" = "8f1ac0f60d675cc6cf13a20ec076568254472551051ad5dd050364d70671bf6b"
 "checksum ron 0.1.7 (registry+https://github.com/rust-lang/crates.io-index)" = "da06feaa07f69125ab9ddc769b11de29090122170b402547f64b86fe16ebc399"
 "checksum runloop 0.1.0 (registry+https://github.com/rust-lang/crates.io-index)" = "5d79b4b604167921892e84afbbaad9d5ad74e091bf6c511d9dbfb0593f09fabd"
 "checksum rust-ini 0.10.3 (registry+https://github.com/rust-lang/crates.io-index)" = "8a654c5bda722c699be6b0fe4c0d90de218928da5b724c3e467fc48865c37263"
 "checksum rustc-serialize 0.3.24 (registry+https://github.com/rust-lang/crates.io-index)" = "dcf128d1287d2ea9d80910b5f1120d0b8eede3fbf1abe91c40d39ea7d51e6fda"
+"checksum rustc_version 0.2.1 (registry+https://github.com/rust-lang/crates.io-index)" = "b9743a7670d88d5d52950408ecdb7c71d8986251ab604d4689dd2ca25c9bca69"
 "checksum safemem 0.2.0 (registry+https://github.com/rust-lang/crates.io-index)" = "e27a8b19b835f7aea908818e871f5cc3a5a186550c30773be987e155e8163d8f"
 "checksum same-file 1.0.2 (registry+https://github.com/rust-lang/crates.io-index)" = "cfb6eded0b06a0b512c8ddbcf04089138c9b4362c2f696f3c3d76039d68f3637"
 "checksum scoped-tls 0.1.0 (registry+https://github.com/rust-lang/crates.io-index)" = "f417c22df063e9450888a7561788e9bd46d3bb3c1466435b4eccb903807f147d"
 "checksum scopeguard 0.3.2 (registry+https://github.com/rust-lang/crates.io-index)" = "c79eb2c3ac4bc2507cda80e7f3ac5b88bd8eae4c0914d5663e6a8933994be918"
 "checksum semver 0.6.0 (registry+https://github.com/rust-lang/crates.io-index)" = "7a3186ec9e65071a2095434b1f5bb24838d4e8e130f584c790f6033c79943537"
 "checksum semver-parser 0.7.0 (registry+https://github.com/rust-lang/crates.io-index)" = "388a1df253eca08550bef6c72392cfe7c30914bf41df5269b68cbd6ff8f570a3"
 "checksum serde 1.0.66 (registry+https://github.com/rust-lang/crates.io-index)" = "e9a2d9a9ac5120e0f768801ca2b58ad6eec929dc9d1d616c162f208869c2ce95"
 "checksum serde_bytes 0.10.4 (registry+https://github.com/rust-lang/crates.io-index)" = "adb6e51a6b3696b301bc221d785f898b4457c619b51d7ce195a6d20baecb37b3"
new file mode 100644
--- /dev/null
+++ b/third_party/rust/rustc_version/.cargo-checksum.json
@@ -0,0 +1,1 @@
+{"files":{".travis.yml":"bf8d4e64585fb3976fe433a6a8835f4a134c611392a597c76bec263d84fa55e7","Cargo.toml":"2f437f4dd58d6813bfa542ffb1ed4c970c3670739f92c41346230e7a5b05796a","LICENSE-APACHE":"a60eea817514531668d7e00765731449fe14d059d3249e0bc93b36de45f759f2","LICENSE-MIT":"c9a75f18b9ab2927829a208fc6aa2cf4e63b8420887ba29cdb265d6619ae82d5","README.md":"b4cb2c1de00ae7382a77431d221a52e10a8a62170cdc1a2ad1c1e711bea7817f","src/errors.rs":"b28c2eeb1278fc3e8d68a64b177034faed67f6762335729d3a6d1e61be8fb034","src/lib.rs":"6a5d5ceb57cf03955af1dbb80a6401ca6d5eac65211d0594354b38b465ce7b45"},"package":"b9743a7670d88d5d52950408ecdb7c71d8986251ab604d4689dd2ca25c9bca69"}
\ No newline at end of file
new file mode 100644
--- /dev/null
+++ b/third_party/rust/rustc_version/.travis.yml
@@ -0,0 +1,21 @@
+language: rust
+rust:
+- nightly
+- beta
+- stable
+before_script:
+- |
+  pip install 'travis-cargo<0.2' --user &&
+  export PATH=$HOME/.local/bin:$PATH
+script:
+- |
+  travis-cargo build &&
+  travis-cargo test &&
+  travis-cargo bench &&
+  travis-cargo --only stable doc
+after_success:
+- travis-cargo --only stable doc-upload
+env:
+  global:
+  - TRAVIS_CARGO_NIGHTLY_FEATURE=""
+  - secure: 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
new file mode 100644
--- /dev/null
+++ b/third_party/rust/rustc_version/Cargo.toml
@@ -0,0 +1,15 @@
+[package]
+name = "rustc_version"
+version = "0.2.1"
+authors = ["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 = "http://kimundi.github.io/rustc-version-rs/rustc_version/index.html"
+
+repository = "https://github.com/Kimundi/rustc-version-rs"
+keywords = ["version", "rustc"]
+
+[dependencies]
+semver = "0.6"
new file mode 100644
--- /dev/null
+++ b/third_party/rust/rustc_version/LICENSE-APACHE
@@ -0,0 +1,201 @@
+                              Apache License
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new file mode 100644
--- /dev/null
+++ b/third_party/rust/rustc_version/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
+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.
new file mode 100644
--- /dev/null
+++ b/third_party/rust/rustc_version/README.md
@@ -0,0 +1,75 @@
+rustc-version-rs
+==============
+
+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.
+
+[![Travis-CI Status](https://travis-ci.org/Kimundi/rustc-version-rs.png?branch=master)](https://travis-ci.org/Kimundi/rustc-version-rs)
+
+# 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
+[dependencies]
+rustc_version = "0.2"
+```
+
+...and see the [docs](http://kimundi.github.io/rustc-version-rs/rustc_version/index.html) for how to use it.
+
+# Example
+
+```rust
+// This could be a cargo build script
+
+extern crate rustc_version;
+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.
new file mode 100644
--- /dev/null
+++ b/third_party/rust/rustc_version/src/errors.rs
@@ -0,0 +1,79 @@
+use std::{self, error, fmt, io, str};
+use semver::{self, Identifier};
+
+/// The error type for this crate.
+#[derive(Debug)]
+pub enum Error {
+    /// An error ocurrend when executing the `rustc` command.
+    CouldNotExecuteCommand(io::Error),
+    /// 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 ocurred in parsing a `VersionReq`.
+    ReqParseError(semver::ReqParseError),
+    /// An error ocurred in parsing the semver.
+    SemVerError(semver::SemVerError),
+    /// The pre-release tag is unknown.
+    UnknownPreReleaseTag(Identifier),
+}
+use Error::*;
+
+impl fmt::Display for Error {
+    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
+        use std::error::Error;
+        match *self {
+            CouldNotExecuteCommand(ref e) => write!(f, "{}: {}", self.description(), e),
+            Utf8Error(_) => write!(f, "{}", self.description()),
+            UnexpectedVersionFormat => write!(f, "{}", self.description()),
+            ReqParseError(ref e) => write!(f, "{}: {}", self.description(), e),
+            SemVerError(ref e) => write!(f, "{}: {}", self.description(), e),
+            UnknownPreReleaseTag(ref i) => write!(f, "{}: {}", self.description(), i),
+        }
+    }
+}
+
+impl error::Error for Error {
+    fn cause(&self) -> Option<&error::Error> {
+        match *self {
+            CouldNotExecuteCommand(ref e) => Some(e),
+            Utf8Error(ref e) => Some(e),
+            UnexpectedVersionFormat => None,
+            ReqParseError(ref e) => Some(e),
+            SemVerError(ref e) => Some(e),
+            UnknownPreReleaseTag(_) => None,
+        }
+    }
+
+    fn description(&self) -> &str {
+        match *self {
+            CouldNotExecuteCommand(_) => "could not execute command",
+            Utf8Error(_) => "invalid UTF-8 output from `rustc -vV`",
+            UnexpectedVersionFormat => "unexpected `rustc -vV` format",
+            ReqParseError(_) => "error parsing version requirement",
+            SemVerError(_) => "error parsing version",
+            UnknownPreReleaseTag(_) => "unknown pre-release tag",
+        }
+    }
+}
+
+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::SemVerError => SemVerError,
+    semver::ReqParseError => ReqParseError,
+}
+
+/// The result type for this crate.
+pub type Result<T> = std::result::Result<T, Error>;
new file mode 100644
--- /dev/null
+++ b/third_party/rust/rustc_version/src/lib.rs
@@ -0,0 +1,353 @@
+// 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
+//!
+//! extern crate rustc_version;
+//! 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");
+//!     }
+//! }
+//! ```
+
+extern crate semver;
+use semver::Identifier;
+use std::process::Command;
+use std::{env, str};
+use std::ffi::OsString;
+
+// Convenience re-export to allow version comparison without needing to add
+// semver crate.
+pub use semver::Version;
+
+mod errors;
+pub use errors::{Error, Result};
+
+/// 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,
+}
+
+/// Rustc version plus metada 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,
+}
+
+impl VersionMeta {
+    /// Returns the version metadata for `cmd`, which should be a `rustc` command.
+    pub fn for_command(cmd: Command) -> Result<VersionMeta> {
+        let mut cmd = cmd;
+
+        let out = match cmd.arg("-vV").output() {
+            Err(e) => return Err(Error::CouldNotExecuteCommand(e)),
+            Ok(out) => out,
+        };
+        let out = try!(str::from_utf8(&out.stdout));
+
+        version_meta_for(out)
+    }
+}
+
+/// Returns the `rustc` SemVer version.
+pub fn version() -> Result<Version> {
+    Ok(try!(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 out: Vec<_> = verbose_version_string.lines().collect();
+
+    if !(out.len() >= 6 && out.len() <= 8) {
+        return Err(Error::UnexpectedVersionFormat);
+    }
+
+    let short_version_string = out[0];
+
+    fn expect_prefix<'a>(line: &'a str, prefix: &str) -> Result<&'a str> {
+        match line.starts_with(prefix) {
+            true => Ok(&line[prefix.len()..]),
+            false => Err(Error::UnexpectedVersionFormat),
+        }
+    }
+
+    let commit_hash = match try!(expect_prefix(out[2], "commit-hash: ")) {
+        "unknown" => None,
+        hash => Some(hash.to_owned()),
+    };
+
+    let commit_date = match try!(expect_prefix(out[3], "commit-date: ")) {
+        "unknown" => None,
+        hash => Some(hash.to_owned()),
+    };
+
+    // Handle that the build date may or may not be present.
+    let mut idx = 4;
+    let mut build_date = None;
+    if out[idx].starts_with("build-date") {
+        build_date = match try!(expect_prefix(out[idx], "build-date: ")) {
+            "unknown" => None,
+            s => Some(s.to_owned()),
+        };
+        idx = idx + 1;
+    }
+
+    let host = try!(expect_prefix(out[idx], "host: "));
+    idx = idx + 1;
+    let release = try!(expect_prefix(out[idx], "release: "));
+
+    let semver: Version = try!(release.parse());
+
+    let channel = if semver.pre.is_empty() {
+        Channel::Stable
+    } else {
+        match semver.pre[0] {
+            Identifier::AlphaNumeric(ref s)
+                if s == "dev" => Channel::Dev,
+            Identifier::AlphaNumeric(ref s)
+                if s == "beta" => Channel::Beta,
+            Identifier::AlphaNumeric(ref s)
+                if s == "nightly" => Channel::Nightly,
+            ref x => return Err(Error::UnknownPreReleaseTag(x.clone())),
+        }
+    };
+
+    Ok(VersionMeta {
+        semver: semver,
+        commit_hash: commit_hash,
+        commit_date: commit_date,
+        build_date: build_date,
+        channel: channel,
+        host: host.into(),
+        short_version_string: short_version_string.into(),
+    })
+}
+
+#[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_unexpected() {
+    let res = 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
+rust-birthday: 2015-05-14
+host: x86_64-unknown-linux-gnu
+release: 1.0.0");
+
+    assert!(match res {
+        Err(Error::UnexpectedVersionFormat) => true,
+        _ => false,
+    });
+
+}
+
+#[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)");
+}
+
+
+#[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");
+}
+
+#[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)");
+}
+
+#[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)");
+}
+
+#[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)");
+}
+
+/*
+#[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!();
+
+}
+*/
--- a/toolkit/library/rust/shared/Cargo.toml
+++ b/toolkit/library/rust/shared/Cargo.toml
@@ -23,16 +23,21 @@ audioipc-client = { path = "../../../../
 audioipc-server = { path = "../../../../media/audioipc/server", optional = true }
 u2fhid = { path = "../../../../dom/webauthn/u2f-hid-rs" }
 rsdparsa_capi = { path = "../../../../media/webrtc/signaling/src/sdp/rsdparsa_capi" }
 # We have these to enforce common feature sets for said crates.
 log = {version = "0.4", features = ["release_max_level_info"]}
 env_logger = {version = "0.5", default-features = false} # disable `regex` to reduce code size
 cose-c = { version = "0.1.5" }
 
+[build-dependencies]
+# Use exactly version 0.2.1, which uses semver 0.6, which other crates
+# require (0.2.2 requires 0.9)
+rustc_version = "=0.2.1"
+
 [features]
 default = []
 bindgen = ["geckoservo/bindgen"]
 servo = ["geckoservo"]
 quantum_render = ["webrender_bindings"]
 cubeb-remoting = ["cubeb-sys", "audioipc-client", "audioipc-server"]
 cubeb_pulse_rust = ["cubeb-sys", "cubeb-pulse"]
 gecko_debug = ["geckoservo/gecko_debug", "nsstring/gecko_debug"]