Bug 1471096 - Vendor rustc_version. r=froydnj draft
authorMike Hommey <mh+mozilla@glandium.org>
Tue, 26 Jun 2018 10:00:26 +0900
changeset 811112 b6cab86b529857c0beeb235d740461f953e69516
parent 811032 86de2687105da279cef2cc2cf493d295d5340e62
child 811113 6b2f78aadfcce5f511466b7b2239b93c84083250
push id114188
push userbmo:mh+mozilla@glandium.org
push dateTue, 26 Jun 2018 22:27:13 +0000
reviewersfroydnj
bugs1471096
milestone63.0a1
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"]