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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 09:22:09 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 09:22:09 +0000
commit43a97878ce14b72f0981164f87f2e35e14151312 (patch)
tree620249daf56c0258faa40cbdcf9cfba06de2a846 /third_party/rust/rustversion/src/lib.rs
parentInitial commit. (diff)
downloadfirefox-43a97878ce14b72f0981164f87f2e35e14151312.tar.xz
firefox-43a97878ce14b72f0981164f87f2e35e14151312.zip
Adding upstream version 110.0.1.upstream/110.0.1upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'third_party/rust/rustversion/src/lib.rs')
-rw-r--r--third_party/rust/rustversion/src/lib.rs247
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diff --git a/third_party/rust/rustversion/src/lib.rs b/third_party/rust/rustversion/src/lib.rs
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+//! [![github]](https://github.com/dtolnay/rustversion)&ensp;[![crates-io]](https://crates.io/crates/rustversion)&ensp;[![docs-rs]](https://docs.rs/rustversion)
+//!
+//! [github]: https://img.shields.io/badge/github-8da0cb?style=for-the-badge&labelColor=555555&logo=github
+//! [crates-io]: https://img.shields.io/badge/crates.io-fc8d62?style=for-the-badge&labelColor=555555&logo=rust
+//! [docs-rs]: https://img.shields.io/badge/docs.rs-66c2a5?style=for-the-badge&labelColor=555555&logo=docs.rs
+//!
+//! <br>
+//!
+//! This crate provides macros for conditional compilation according to rustc
+//! compiler version, analogous to [`#[cfg(...)]`][cfg] and
+//! [`#[cfg_attr(...)]`][cfg_attr].
+//!
+//! [cfg]: https://doc.rust-lang.org/reference/conditional-compilation.html#the-cfg-attribute
+//! [cfg_attr]: https://doc.rust-lang.org/reference/conditional-compilation.html#the-cfg_attr-attribute
+//!
+//! <br>
+//!
+//! # Selectors
+//!
+//! - <p style="margin-left:50px;text-indent:-50px">
+//! <b><code>#[rustversion::stable]</code></b>
+//! —<br>
+//! True on any stable compiler.
+//! </p>
+//!
+//! - <p style="margin-left:50px;text-indent:-50px">
+//! <b><code>#[rustversion::stable(1.34)]</code></b>
+//! —<br>
+//! True on exactly the specified stable compiler.
+//! </p>
+//!
+//! - <p style="margin-left:50px;text-indent:-50px">
+//! <b><code>#[rustversion::beta]</code></b>
+//! —<br>
+//! True on any beta compiler.
+//! </p>
+//!
+//! - <p style="margin-left:50px;text-indent:-50px">
+//! <b><code>#[rustversion::nightly]</code></b>
+//! —<br>
+//! True on any nightly compiler or dev build.
+//! </p>
+//!
+//! - <p style="margin-left:50px;text-indent:-50px">
+//! <b><code>#[rustversion::nightly(2019-01-01)]</code></b>
+//! —<br>
+//! True on exactly one nightly.
+//! </p>
+//!
+//! - <p style="margin-left:50px;text-indent:-50px">
+//! <b><code>#[rustversion::since(1.34)]</code></b>
+//! —<br>
+//! True on that stable release and any later compiler, including beta and
+//! nightly.
+//! </p>
+//!
+//! - <p style="margin-left:50px;text-indent:-50px">
+//! <b><code>#[rustversion::since(2019-01-01)]</code></b>
+//! —<br>
+//! True on that nightly and all newer ones.
+//! </p>
+//!
+//! - <p style="margin-left:50px;text-indent:-50px">
+//! <b><code>#[rustversion::before(</code></b><i>version or date</i><b><code>)]</code></b>
+//! —<br>
+//! Negative of <i>#[rustversion::since(...)]</i>.
+//! </p>
+//!
+//! - <p style="margin-left:50px;text-indent:-50px">
+//! <b><code>#[rustversion::not(</code></b><i>selector</i><b><code>)]</code></b>
+//! —<br>
+//! Negative of any selector; for example <i>#[rustversion::not(nightly)]</i>.
+//! </p>
+//!
+//! - <p style="margin-left:50px;text-indent:-50px">
+//! <b><code>#[rustversion::any(</code></b><i>selectors...</i><b><code>)]</code></b>
+//! —<br>
+//! True if any of the comma-separated selectors is true; for example
+//! <i>#[rustversion::any(stable, beta)]</i>.
+//! </p>
+//!
+//! - <p style="margin-left:50px;text-indent:-50px">
+//! <b><code>#[rustversion::all(</code></b><i>selectors...</i><b><code>)]</code></b>
+//! —<br>
+//! True if all of the comma-separated selectors are true; for example
+//! <i>#[rustversion::all(since(1.31), before(1.34))]</i>.
+//! </p>
+//!
+//! - <p style="margin-left:50px;text-indent:-50px">
+//! <b><code>#[rustversion::attr(</code></b><i>selector</i><b><code>, </code></b><i>attribute</i><b><code>)]</code></b>
+//! —<br>
+//! For conditional inclusion of attributes; analogous to
+//! <code>cfg_attr</code>.
+//! </p>
+//!
+//! <br>
+//!
+//! # Use cases
+//!
+//! Providing additional trait impls as types are stabilized in the standard library
+//! without breaking compatibility with older compilers; in this case Pin\<P\>
+//! stabilized in [Rust 1.33][pin]:
+//!
+//! [pin]: https://blog.rust-lang.org/2019/02/28/Rust-1.33.0.html#pinning
+//!
+//! ```
+//! # trait MyTrait {}
+//! #
+//! #[rustversion::since(1.33)]
+//! use std::pin::Pin;
+//!
+//! #[rustversion::since(1.33)]
+//! impl<P: MyTrait> MyTrait for Pin<P> {
+//! /* ... */
+//! }
+//! ```
+//!
+//! Similar but for language features; the ability to control alignment greater than
+//! 1 of packed structs was stabilized in [Rust 1.33][packed].
+//!
+//! [packed]: https://github.com/rust-lang/rust/blob/master/RELEASES.md#version-1330-2019-02-28
+//!
+//! ```
+//! #[rustversion::attr(before(1.33), repr(packed))]
+//! #[rustversion::attr(since(1.33), repr(packed(2)))]
+//! struct Six(i16, i32);
+//!
+//! fn main() {
+//! println!("{}", std::mem::align_of::<Six>());
+//! }
+//! ```
+//!
+//! Augmenting code with `const` as const impls are stabilized in the standard
+//! library. This use of `const` as an attribute is recognized as a special case
+//! by the rustversion::attr macro.
+//!
+//! ```
+//! use std::time::Duration;
+//!
+//! #[rustversion::attr(since(1.32), const)]
+//! fn duration_as_days(dur: Duration) -> u64 {
+//! dur.as_secs() / 60 / 60 / 24
+//! }
+//! ```
+//!
+//! <br>
+
+#![allow(
+ clippy::cast_lossless,
+ clippy::cast_possible_truncation,
+ clippy::derive_partial_eq_without_eq,
+ clippy::doc_markdown,
+ clippy::enum_glob_use,
+ clippy::from_iter_instead_of_collect,
+ // https://github.com/rust-lang/rust-clippy/issues/8539
+ clippy::iter_with_drain,
+ clippy::module_name_repetitions,
+ clippy::must_use_candidate,
+ clippy::needless_doctest_main,
+ clippy::needless_pass_by_value,
+ clippy::redundant_else,
+ clippy::toplevel_ref_arg,
+ clippy::unreadable_literal
+)]
+
+extern crate proc_macro;
+
+mod attr;
+mod bound;
+mod constfn;
+mod date;
+mod error;
+mod expand;
+mod expr;
+mod iter;
+mod release;
+mod time;
+mod token;
+mod version;
+
+use crate::error::Error;
+use crate::version::Version;
+use proc_macro::TokenStream;
+
+const RUSTVERSION: Version = include!(concat!(env!("OUT_DIR"), "/version.expr"));
+
+#[proc_macro_attribute]
+pub fn stable(args: TokenStream, input: TokenStream) -> TokenStream {
+ expand::cfg("stable", args, input)
+}
+
+#[proc_macro_attribute]
+pub fn beta(args: TokenStream, input: TokenStream) -> TokenStream {
+ expand::cfg("beta", args, input)
+}
+
+#[proc_macro_attribute]
+pub fn nightly(args: TokenStream, input: TokenStream) -> TokenStream {
+ expand::cfg("nightly", args, input)
+}
+
+#[proc_macro_attribute]
+pub fn since(args: TokenStream, input: TokenStream) -> TokenStream {
+ expand::cfg("since", args, input)
+}
+
+#[proc_macro_attribute]
+pub fn before(args: TokenStream, input: TokenStream) -> TokenStream {
+ expand::cfg("before", args, input)
+}
+
+#[proc_macro_attribute]
+pub fn not(args: TokenStream, input: TokenStream) -> TokenStream {
+ expand::cfg("not", args, input)
+}
+
+#[proc_macro_attribute]
+pub fn any(args: TokenStream, input: TokenStream) -> TokenStream {
+ expand::cfg("any", args, input)
+}
+
+#[proc_macro_attribute]
+pub fn all(args: TokenStream, input: TokenStream) -> TokenStream {
+ expand::cfg("all", args, input)
+}
+
+#[proc_macro_attribute]
+pub fn attr(args: TokenStream, input: TokenStream) -> TokenStream {
+ attr::parse(args)
+ .and_then(|args| expand::try_attr(args, input))
+ .unwrap_or_else(Error::into_compile_error)
+}
+
+#[cfg(not(cfg_macro_not_allowed))]
+#[proc_macro]
+pub fn cfg(input: TokenStream) -> TokenStream {
+ use proc_macro::{Ident, Span, TokenTree};
+ (|| {
+ let ref mut args = iter::new(input);
+ let expr = expr::parse(args)?;
+ token::parse_end(args)?;
+ let boolean = expr.eval(RUSTVERSION);
+ let ident = Ident::new(&boolean.to_string(), Span::call_site());
+ Ok(TokenStream::from(TokenTree::Ident(ident)))
+ })()
+ .unwrap_or_else(Error::into_compile_error)
+}