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Diffstat (limited to 'vendor/version_check/src/lib.rs')
| -rw-r--r-- | vendor/version_check/src/lib.rs | 493 |
1 files changed, 493 insertions, 0 deletions
diff --git a/vendor/version_check/src/lib.rs b/vendor/version_check/src/lib.rs new file mode 100644 index 000000000..6c1607482 --- /dev/null +++ b/vendor/version_check/src/lib.rs @@ -0,0 +1,493 @@ +//! This tiny crate checks that the running or installed `rustc` meets some +//! version requirements. The version is queried by calling the Rust compiler +//! with `--version`. The path to the compiler is determined first via the +//! `RUSTC` environment variable. If it is not set, then `rustc` is used. If +//! that fails, no determination is made, and calls return `None`. +//! +//! # Examples +//! +//! * Set a `cfg` flag in `build.rs` if the running compiler was determined to +//! be at least version `1.13.0`: +//! +//! ```rust +//! extern crate version_check as rustc; +//! +//! if rustc::is_min_version("1.13.0").unwrap_or(false) { +//! println!("cargo:rustc-cfg=question_mark_operator"); +//! } +//! ``` +//! +//! See [`is_max_version`] or [`is_exact_version`] to check if the compiler +//! is _at most_ or _exactly_ a certain version. +//! +//! * Check that the running compiler was released on or after `2018-12-18`: +//! +//! ```rust +//! extern crate version_check as rustc; +//! +//! match rustc::is_min_date("2018-12-18") { +//! Some(true) => "Yep! It's recent!", +//! Some(false) => "No, it's older.", +//! None => "Couldn't determine the rustc version." +//! }; +//! ``` +//! +//! See [`is_max_date`] or [`is_exact_date`] to check if the compiler was +//! released _prior to_ or _exactly on_ a certain date. +//! +//! * Check that the running compiler supports feature flags: +//! +//! ```rust +//! extern crate version_check as rustc; +//! +//! match rustc::is_feature_flaggable() { +//! Some(true) => "Yes! It's a dev or nightly release!", +//! Some(false) => "No, it's stable or beta.", +//! None => "Couldn't determine the rustc version." +//! }; +//! ``` +//! +//! * Check that the running compiler supports a specific feature: +//! +//! ```rust +//! extern crate version_check as rustc; +//! +//! if let Some(true) = rustc::supports_feature("doc_cfg") { +//! println!("cargo:rustc-cfg=has_doc_cfg"); +//! } +//! ``` +//! +//! * Check that the running compiler is on the stable channel: +//! +//! ```rust +//! extern crate version_check as rustc; +//! +//! match rustc::Channel::read() { +//! Some(c) if c.is_stable() => format!("Yes! It's stable."), +//! Some(c) => format!("No, the channel {} is not stable.", c), +//! None => format!("Couldn't determine the rustc version.") +//! }; +//! ``` +//! +//! To interact with the version, release date, and release channel as structs, +//! use [`Version`], [`Date`], and [`Channel`], respectively. The [`triple()`] +//! function returns all three values efficiently. +//! +//! # Alternatives +//! +//! This crate is dead simple with no dependencies. If you need something more +//! and don't care about panicking if the version cannot be obtained, or if you +//! don't mind adding dependencies, see +//! [rustc_version](https://crates.io/crates/rustc_version). + +#![allow(deprecated)] + +mod version; +mod channel; +mod date; + +use std::env; +use std::process::Command; + +#[doc(inline)] pub use version::*; +#[doc(inline)] pub use channel::*; +#[doc(inline)] pub use date::*; + +/// Parses (version, date) as available from rustc version string. +fn version_and_date_from_rustc_version(s: &str) -> (Option<String>, Option<String>) { + let last_line = s.lines().last().unwrap_or(s); + let mut components = last_line.trim().split(" "); + let version = components.nth(1); + let date = components.filter(|c| c.ends_with(')')).next() + .map(|s| s.trim_right().trim_right_matches(")").trim_left().trim_left_matches('(')); + (version.map(|s| s.to_string()), date.map(|s| s.to_string())) +} + +/// Parses (version, date) as available from rustc verbose version output. +fn version_and_date_from_rustc_verbose_version(s: &str) -> (Option<String>, Option<String>) { + let (mut version, mut date) = (None, None); + for line in s.lines() { + let split = |s: &str| s.splitn(2, ":").nth(1).map(|s| s.trim().to_string()); + match line.trim().split(" ").nth(0) { + Some("rustc") => { + let (v, d) = version_and_date_from_rustc_version(line); + version = version.or(v); + date = date.or(d); + }, + Some("release:") => version = split(line), + Some("commit-date:") if line.ends_with("unknown") => date = None, + Some("commit-date:") => date = split(line), + _ => continue + } + } + + (version, date) +} + +/// Returns (version, date) as available from `rustc --version`. +fn get_version_and_date() -> Option<(Option<String>, Option<String>)> { + let rustc = env::var("RUSTC").unwrap_or_else(|_| "rustc".to_string()); + Command::new(rustc).arg("--verbose").arg("--version").output().ok() + .and_then(|output| String::from_utf8(output.stdout).ok()) + .map(|s| version_and_date_from_rustc_verbose_version(&s)) +} + +/// Reads the triple of [`Version`], [`Channel`], and [`Date`] of the installed +/// or running `rustc`. +/// +/// If any attribute cannot be determined (see the [top-level +/// documentation](crate)), returns `None`. +/// +/// To obtain only one of three attributes, use [`Version::read()`], +/// [`Channel::read()`], or [`Date::read()`]. +pub fn triple() -> Option<(Version, Channel, Date)> { + let (version_str, date_str) = match get_version_and_date() { + Some((Some(version), Some(date))) => (version, date), + _ => return None + }; + + // Can't use `?` or `try!` for `Option` in 1.0.0. + match Version::parse(&version_str) { + Some(version) => match Channel::parse(&version_str) { + Some(channel) => match Date::parse(&date_str) { + Some(date) => Some((version, channel, date)), + _ => None, + }, + _ => None, + }, + _ => None + } +} + +/// Checks that the running or installed `rustc` was released **on or after** +/// some date. +/// +/// The format of `min_date` must be YYYY-MM-DD. For instance: `2016-12-20` or +/// `2017-01-09`. +/// +/// If the date cannot be retrieved or parsed, or if `min_date` could not be +/// parsed, returns `None`. Otherwise returns `true` if the installed `rustc` +/// was release on or after `min_date` and `false` otherwise. +pub fn is_min_date(min_date: &str) -> Option<bool> { + match (Date::read(), Date::parse(min_date)) { + (Some(rustc_date), Some(min_date)) => Some(rustc_date >= min_date), + _ => None + } +} + +/// Checks that the running or installed `rustc` was released **on or before** +/// some date. +/// +/// The format of `max_date` must be YYYY-MM-DD. For instance: `2016-12-20` or +/// `2017-01-09`. +/// +/// If the date cannot be retrieved or parsed, or if `max_date` could not be +/// parsed, returns `None`. Otherwise returns `true` if the installed `rustc` +/// was release on or before `max_date` and `false` otherwise. +pub fn is_max_date(max_date: &str) -> Option<bool> { + match (Date::read(), Date::parse(max_date)) { + (Some(rustc_date), Some(max_date)) => Some(rustc_date <= max_date), + _ => None + } +} + +/// Checks that the running or installed `rustc` was released **exactly** on +/// some date. +/// +/// The format of `date` must be YYYY-MM-DD. For instance: `2016-12-20` or +/// `2017-01-09`. +/// +/// If the date cannot be retrieved or parsed, or if `date` could not be parsed, +/// returns `None`. Otherwise returns `true` if the installed `rustc` was +/// release on `date` and `false` otherwise. +pub fn is_exact_date(date: &str) -> Option<bool> { + match (Date::read(), Date::parse(date)) { + (Some(rustc_date), Some(date)) => Some(rustc_date == date), + _ => None + } +} + +/// Checks that the running or installed `rustc` is **at least** some minimum +/// version. +/// +/// The format of `min_version` is a semantic version: `1.3.0`, `1.15.0-beta`, +/// `1.14.0`, `1.16.0-nightly`, etc. +/// +/// If the version cannot be retrieved or parsed, or if `min_version` could not +/// be parsed, returns `None`. Otherwise returns `true` if the installed `rustc` +/// is at least `min_version` and `false` otherwise. +pub fn is_min_version(min_version: &str) -> Option<bool> { + match (Version::read(), Version::parse(min_version)) { + (Some(rustc_ver), Some(min_ver)) => Some(rustc_ver >= min_ver), + _ => None + } +} + +/// Checks that the running or installed `rustc` is **at most** some maximum +/// version. +/// +/// The format of `max_version` is a semantic version: `1.3.0`, `1.15.0-beta`, +/// `1.14.0`, `1.16.0-nightly`, etc. +/// +/// If the version cannot be retrieved or parsed, or if `max_version` could not +/// be parsed, returns `None`. Otherwise returns `true` if the installed `rustc` +/// is at most `max_version` and `false` otherwise. +pub fn is_max_version(max_version: &str) -> Option<bool> { + match (Version::read(), Version::parse(max_version)) { + (Some(rustc_ver), Some(max_ver)) => Some(rustc_ver <= max_ver), + _ => None + } +} + +/// Checks that the running or installed `rustc` is **exactly** some version. +/// +/// The format of `version` is a semantic version: `1.3.0`, `1.15.0-beta`, +/// `1.14.0`, `1.16.0-nightly`, etc. +/// +/// If the version cannot be retrieved or parsed, or if `version` could not be +/// parsed, returns `None`. Otherwise returns `true` if the installed `rustc` is +/// exactly `version` and `false` otherwise. +pub fn is_exact_version(version: &str) -> Option<bool> { + match (Version::read(), Version::parse(version)) { + (Some(rustc_ver), Some(version)) => Some(rustc_ver == version), + _ => None + } +} + +/// Checks whether the running or installed `rustc` supports feature flags. +/// +/// In other words, if the channel is either "nightly" or "dev". +/// +/// Note that support for specific `rustc` features can be enabled or disabled +/// via the `allow-features` compiler flag, which this function _does not_ +/// check. That is, this function _does not_ check whether a _specific_ feature +/// is supported, but instead whether features are supported at all. To check +/// for support for a specific feature, use [`supports_feature()`]. +/// +/// If the version could not be determined, returns `None`. Otherwise returns +/// `true` if the running version supports feature flags and `false` otherwise. +pub fn is_feature_flaggable() -> Option<bool> { + Channel::read().map(|c| c.supports_features()) +} + +/// Checks whether the running or installed `rustc` supports `feature`. +/// +/// Returns _true_ _iff_ [`is_feature_flaggable()`] returns `true` _and_ the +/// feature is not disabled via exclusion in `allow-features` via `RUSTFLAGS` or +/// `CARGO_ENCODED_RUSTFLAGS`. If the version could not be determined, returns +/// `None`. +/// +/// # Example +/// +/// ```rust +/// use version_check as rustc; +/// +/// if let Some(true) = rustc::supports_feature("doc_cfg") { +/// println!("cargo:rustc-cfg=has_doc_cfg"); +/// } +/// ``` +pub fn supports_feature(feature: &str) -> Option<bool> { + match is_feature_flaggable() { + Some(true) => { /* continue */ } + Some(false) => return Some(false), + None => return None, + } + + let env_flags = env::var_os("CARGO_ENCODED_RUSTFLAGS") + .map(|flags| (flags, '\x1f')) + .or_else(|| env::var_os("RUSTFLAGS").map(|flags| (flags, ' '))); + + if let Some((flags, delim)) = env_flags { + const ALLOW_FEATURES: &'static str = "allow-features="; + + let rustflags = flags.to_string_lossy(); + let allow_features = rustflags.split(delim) + .map(|flag| flag.trim_left_matches("-Z").trim()) + .filter(|flag| flag.starts_with(ALLOW_FEATURES)) + .map(|flag| &flag[ALLOW_FEATURES.len()..]); + + if let Some(allow_features) = allow_features.last() { + return Some(allow_features.split(',').any(|f| f.trim() == feature)); + } + } + + // If there are no `RUSTFLAGS` or `CARGO_ENCODED_RUSTFLAGS` or they don't + // contain an `allow-features` flag, assume compiler allows all features. + Some(true) +} + +#[cfg(test)] +mod tests { + use std::{env, fs}; + + use super::version_and_date_from_rustc_version; + use super::version_and_date_from_rustc_verbose_version; + + macro_rules! check_parse { + (@ $f:expr, $s:expr => $v:expr, $d:expr) => ({ + if let (Some(v), d) = $f(&$s) { + let e_d: Option<&str> = $d.into(); + assert_eq!((v, d), ($v.to_string(), e_d.map(|s| s.into()))); + } else { + panic!("{:?} didn't parse for version testing.", $s); + } + }); + ($f:expr, $s:expr => $v:expr, $d:expr) => ({ + let warn = "warning: invalid logging spec 'warning', ignoring it"; + let warn2 = "warning: sorry, something went wrong :(sad)"; + check_parse!(@ $f, $s => $v, $d); + check_parse!(@ $f, &format!("{}\n{}", warn, $s) => $v, $d); + check_parse!(@ $f, &format!("{}\n{}", warn2, $s) => $v, $d); + check_parse!(@ $f, &format!("{}\n{}\n{}", warn, warn2, $s) => $v, $d); + check_parse!(@ $f, &format!("{}\n{}\n{}", warn2, warn, $s) => $v, $d); + }) + } + + macro_rules! check_terse_parse { + ($($s:expr => $v:expr, $d:expr,)+) => {$( + check_parse!(version_and_date_from_rustc_version, $s => $v, $d); + )+} + } + + macro_rules! check_verbose_parse { + ($($s:expr => $v:expr, $d:expr,)+) => {$( + check_parse!(version_and_date_from_rustc_verbose_version, $s => $v, $d); + )+} + } + + #[test] + fn test_version_parse() { + check_terse_parse! { + "rustc 1.18.0" => "1.18.0", None, + "rustc 1.8.0" => "1.8.0", None, + "rustc 1.20.0-nightly" => "1.20.0-nightly", None, + "rustc 1.20" => "1.20", None, + "rustc 1.3" => "1.3", None, + "rustc 1" => "1", None, + "rustc 1.5.1-beta" => "1.5.1-beta", None, + "rustc 1.20.0 (2017-07-09)" => "1.20.0", Some("2017-07-09"), + "rustc 1.20.0-dev (2017-07-09)" => "1.20.0-dev", Some("2017-07-09"), + "rustc 1.20.0-nightly (d84693b93 2017-07-09)" => "1.20.0-nightly", Some("2017-07-09"), + "rustc 1.20.0 (d84693b93 2017-07-09)" => "1.20.0", Some("2017-07-09"), + "rustc 1.30.0-nightly (3bc2ca7e4 2018-09-20)" => "1.30.0-nightly", Some("2018-09-20"), + }; + } + + #[test] + fn test_verbose_version_parse() { + check_verbose_parse! { + "rustc 1.0.0 (a59de37e9 2015-05-13) (built 2015-05-14)\n\ + binary: rustc\n\ + commit-hash: a59de37e99060162a2674e3ff45409ac73595c0e\n\ + commit-date: 2015-05-13\n\ + build-date: 2015-05-14\n\ + host: x86_64-unknown-linux-gnu\n\ + release: 1.0.0" => "1.0.0", Some("2015-05-13"), + + "rustc 1.0.0 (a59de37e9 2015-05-13) (built 2015-05-14)\n\ + commit-hash: a59de37e99060162a2674e3ff45409ac73595c0e\n\ + commit-date: 2015-05-13\n\ + build-date: 2015-05-14\n\ + host: x86_64-unknown-linux-gnu\n\ + release: 1.0.0" => "1.0.0", Some("2015-05-13"), + + "rustc 1.50.0 (cb75ad5db 2021-02-10)\n\ + binary: rustc\n\ + commit-hash: cb75ad5db02783e8b0222fee363c5f63f7e2cf5b\n\ + commit-date: 2021-02-10\n\ + host: x86_64-unknown-linux-gnu\n\ + release: 1.50.0" => "1.50.0", Some("2021-02-10"), + + "rustc 1.52.0-nightly (234781afe 2021-03-07)\n\ + binary: rustc\n\ + commit-hash: 234781afe33d3f339b002f85f948046d8476cfc9\n\ + commit-date: 2021-03-07\n\ + host: x86_64-unknown-linux-gnu\n\ + release: 1.52.0-nightly\n\ + LLVM version: 12.0.0" => "1.52.0-nightly", Some("2021-03-07"), + + "rustc 1.41.1\n\ + binary: rustc\n\ + commit-hash: unknown\n\ + commit-date: unknown\n\ + host: x86_64-unknown-linux-gnu\n\ + release: 1.41.1\n\ + LLVM version: 7.0" => "1.41.1", None, + + "rustc 1.49.0\n\ + binary: rustc\n\ + commit-hash: unknown\n\ + commit-date: unknown\n\ + host: x86_64-unknown-linux-gnu\n\ + release: 1.49.0" => "1.49.0", None, + + "rustc 1.50.0 (Fedora 1.50.0-1.fc33)\n\ + binary: rustc\n\ + commit-hash: unknown\n\ + commit-date: unknown\n\ + host: x86_64-unknown-linux-gnu\n\ + release: 1.50.0" => "1.50.0", None, + }; + } + + fn read_static(verbose: bool, channel: &str, minor: usize) -> String { + use std::fs::File; + use std::path::Path; + use std::io::{BufReader, Read}; + + let subdir = if verbose { "verbose" } else { "terse" }; + let path = Path::new(STATIC_PATH) + .join(channel) + .join(subdir) + .join(format!("rustc-1.{}.0", minor)); + + let file = File::open(path).unwrap(); + let mut buf_reader = BufReader::new(file); + let mut contents = String::new(); + buf_reader.read_to_string(&mut contents).unwrap(); + contents + } + + static STATIC_PATH: &'static str = concat!(env!("CARGO_MANIFEST_DIR"), "/static"); + + static DATES: [&'static str; 51] = [ + "2015-05-13", "2015-06-19", "2015-08-03", "2015-09-15", "2015-10-27", + "2015-12-04", "2016-01-19", "2016-02-29", "2016-04-11", "2016-05-18", + "2016-07-03", "2016-08-15", "2016-09-23", "2016-11-07", "2016-12-16", + "2017-01-19", "2017-03-10", "2017-04-24", "2017-06-06", "2017-07-17", + "2017-08-27", "2017-10-09", "2017-11-20", "2018-01-01", "2018-02-12", + "2018-03-25", "2018-05-07", "2018-06-19", "2018-07-30", "2018-09-11", + "2018-10-24", "2018-12-04", "2019-01-16", "2019-02-28", "2019-04-10", + "2019-05-20", "2019-07-03", "2019-08-13", "2019-09-23", "2019-11-04", + "2019-12-16", "2020-01-27", "2020-03-09", "2020-04-20", "2020-06-01", + "2020-07-13", "2020-08-24", "2020-10-07", "2020-11-16", "2020-12-29", + "2021-02-10", + ]; + + #[test] + fn test_stable_compatibility() { + if env::var_os("FORCE_STATIC").is_none() && fs::metadata(STATIC_PATH).is_err() { + // We exclude `/static` when we package `version_check`, so don't + // run if static files aren't present unless we know they should be. + return; + } + + // Ensure we can parse all output from all Linux stable releases. + for v in 0..DATES.len() { + let (version, date) = (&format!("1.{}.0", v), Some(DATES[v])); + check_terse_parse!(read_static(false, "stable", v) => version, date,); + check_verbose_parse!(read_static(true, "stable", v) => version, date,); + } + } + + #[test] + fn test_parse_current() { + let (version, channel) = (::Version::read(), ::Channel::read()); + assert!(version.is_some()); + assert!(channel.is_some()); + + if let Ok(known_channel) = env::var("KNOWN_CHANNEL") { + assert_eq!(channel, ::Channel::parse(&known_channel)); + } + } +} |