From 8ca9c7bbe5f2be252881e1edbd2a2ce97e75244f Mon Sep 17 00:00:00 2001 From: Pascal Hertleif Date: Sat, 24 Aug 2019 17:45:03 +0200 Subject: [PATCH 1/4] Fix tidy feature gate error reporting Feature gate definitions were split into multiple files in #63824 but tidy kept reporting the hard-coded path. Now, it shows the full path to the correct file. --- src/tools/tidy/src/features.rs | 22 +++++++++++++++------- 1 file changed, 15 insertions(+), 7 deletions(-) diff --git a/src/tools/tidy/src/features.rs b/src/tools/tidy/src/features.rs index 468e56001012f..50e9116c778ea 100644 --- a/src/tools/tidy/src/features.rs +++ b/src/tools/tidy/src/features.rs @@ -176,7 +176,10 @@ pub fn check(path: &Path, bad: &mut bool, verbose: bool) -> CollectedFeatures { CollectedFeatures { lib: lib_features, lang: features } } -fn format_features<'a>(features: &'a Features, family: &'a str) -> impl Iterator + 'a { +fn format_features<'a>( + features: &'a Features, + family: &'a str, +) -> impl Iterator + 'a { features.iter().map(move |(name, feature)| { format!("{:<32} {:<8} {:<12} {:<8}", name, @@ -228,7 +231,8 @@ pub fn collect_lang_features(base_src_path: &Path, bad: &mut bool) -> Features { } fn collect_lang_features_in(base: &Path, file: &str, bad: &mut bool) -> Features { - let contents = t!(fs::read_to_string(base.join("libsyntax/feature_gate").join(file))); + let path = base.join("libsyntax/feature_gate").join(file); + let contents = t!(fs::read_to_string(&path)); // We allow rustc-internal features to omit a tracking issue. // To make tidy accept omitting a tracking issue, group the list of features @@ -259,8 +263,9 @@ fn collect_lang_features_in(base: &Path, file: &str, bad: &mut bool) -> Features if in_feature_group { tidy_error!( bad, - // ignore-tidy-linelength - "libsyntax/feature_gate.rs:{}: new feature group is started without ending the previous one", + "{}:{}: \ + new feature group is started without ending the previous one", + path.display(), line_number, ); } @@ -289,7 +294,8 @@ fn collect_lang_features_in(base: &Path, file: &str, bad: &mut bool) -> Features Err(err) => { tidy_error!( bad, - "libsyntax/feature_gate.rs:{}: failed to parse since: {} ({:?})", + "{}:{}: failed to parse since: {} ({:?})", + path.display(), line_number, since_str, err, @@ -301,7 +307,8 @@ fn collect_lang_features_in(base: &Path, file: &str, bad: &mut bool) -> Features if prev_since > since { tidy_error!( bad, - "libsyntax/feature_gate.rs:{}: feature {} is not sorted by since", + "{}:{}: feature {} is not sorted by since", + path.display(), line_number, name, ); @@ -315,7 +322,8 @@ fn collect_lang_features_in(base: &Path, file: &str, bad: &mut bool) -> Features *bad = true; tidy_error!( bad, - "libsyntax/feature_gate.rs:{}: no tracking issue for feature {}", + "{}:{}: no tracking issue for feature {}", + path.display(), line_number, name, ); From c9619a4202bd013f1be2776c328937ddd643e7b7 Mon Sep 17 00:00:00 2001 From: Pascal Hertleif Date: Sat, 24 Aug 2019 17:47:26 +0200 Subject: [PATCH 2/4] Use doc comments for feature gate descriptions This is just in preparation for future usage of these texts. --- src/libsyntax/feature_gate/accepted.rs | 218 +++++++++--------- src/libsyntax/feature_gate/active.rs | 305 +++++++++++++------------ src/libsyntax/feature_gate/removed.rs | 22 +- 3 files changed, 284 insertions(+), 261 deletions(-) diff --git a/src/libsyntax/feature_gate/accepted.rs b/src/libsyntax/feature_gate/accepted.rs index 32a0b76d5f0d8..28e4d2c073c7c 100644 --- a/src/libsyntax/feature_gate/accepted.rs +++ b/src/libsyntax/feature_gate/accepted.rs @@ -3,7 +3,9 @@ use crate::symbol::{Symbol, sym}; macro_rules! declare_features { - ($((accepted, $feature: ident, $ver: expr, $issue: expr, None),)+) => { + ($( + $(#[doc = $doc:tt])* (accepted, $feature:ident, $ver:expr, $issue:expr, None), + )+) => { /// Those language feature has since been Accepted (it was once Active) pub const ACCEPTED_FEATURES: &[(Symbol, &str, Option, Option<&str>)] = &[ $((sym::$feature, $ver, $issue, None)),+ @@ -16,11 +18,11 @@ declare_features! ( // feature-group-start: for testing purposes // ------------------------------------------------------------------------- - // A temporary feature gate used to enable parser extensions needed - // to bootstrap fix for #5723. + /// A temporary feature gate used to enable parser extensions needed + /// to bootstrap fix for #5723. (accepted, issue_5723_bootstrap, "1.0.0", None, None), - // These are used to test this portion of the compiler, - // they don't actually mean anything. + /// These are used to test this portion of the compiler, + /// they don't actually mean anything. (accepted, test_accepted_feature, "1.0.0", None, None), // ------------------------------------------------------------------------- @@ -31,203 +33,203 @@ declare_features! ( // feature-group-start: accepted features // ------------------------------------------------------------------------- - // Allows using associated `type`s in `trait`s. + /// Allows using associated `type`s in `trait`s. (accepted, associated_types, "1.0.0", None, None), - // Allows using assigning a default type to type parameters in algebraic data type definitions. + /// Allows using assigning a default type to type parameters in algebraic data type definitions. (accepted, default_type_params, "1.0.0", None, None), // FIXME: explain `globs`. (accepted, globs, "1.0.0", None, None), - // Allows `macro_rules!` items. + /// Allows `macro_rules!` items. (accepted, macro_rules, "1.0.0", None, None), - // Allows use of `&foo[a..b]` as a slicing syntax. + /// Allows use of `&foo[a..b]` as a slicing syntax. (accepted, slicing_syntax, "1.0.0", None, None), - // Allows struct variants `Foo { baz: u8, .. }` in enums (RFC 418). + /// Allows struct variants `Foo { baz: u8, .. }` in enums (RFC 418). (accepted, struct_variant, "1.0.0", None, None), - // Allows indexing tuples. + /// Allows indexing tuples. (accepted, tuple_indexing, "1.0.0", None, None), - // Allows the use of `if let` expressions. + /// Allows the use of `if let` expressions. (accepted, if_let, "1.0.0", None, None), - // Allows the use of `while let` expressions. + /// Allows the use of `while let` expressions. (accepted, while_let, "1.0.0", None, None), - // Allows using `#![no_std]`. + /// Allows using `#![no_std]`. (accepted, no_std, "1.6.0", None, None), - // Allows overloading augmented assignment operations like `a += b`. + /// Allows overloading augmented assignment operations like `a += b`. (accepted, augmented_assignments, "1.8.0", Some(28235), None), - // Allows empty structs and enum variants with braces. + /// Allows empty structs and enum variants with braces. (accepted, braced_empty_structs, "1.8.0", Some(29720), None), - // Allows `#[deprecated]` attribute. + /// Allows `#[deprecated]` attribute. (accepted, deprecated, "1.9.0", Some(29935), None), - // Allows macros to appear in the type position. + /// Allows macros to appear in the type position. (accepted, type_macros, "1.13.0", Some(27245), None), - // Allows use of the postfix `?` operator in expressions. + /// Allows use of the postfix `?` operator in expressions. (accepted, question_mark, "1.13.0", Some(31436), None), - // Allows `..` in tuple (struct) patterns. + /// Allows `..` in tuple (struct) patterns. (accepted, dotdot_in_tuple_patterns, "1.14.0", Some(33627), None), - // Allows some increased flexibility in the name resolution rules, - // especially around globs and shadowing (RFC 1560). + /// Allows some increased flexibility in the name resolution rules, + /// especially around globs and shadowing (RFC 1560). (accepted, item_like_imports, "1.15.0", Some(35120), None), - // Allows using `Self` and associated types in struct expressions and patterns. + /// Allows using `Self` and associated types in struct expressions and patterns. (accepted, more_struct_aliases, "1.16.0", Some(37544), None), - // Allows elision of `'static` lifetimes in `static`s and `const`s. + /// Allows elision of `'static` lifetimes in `static`s and `const`s. (accepted, static_in_const, "1.17.0", Some(35897), None), - // Allows field shorthands (`x` meaning `x: x`) in struct literal expressions. + /// Allows field shorthands (`x` meaning `x: x`) in struct literal expressions. (accepted, field_init_shorthand, "1.17.0", Some(37340), None), - // Allows the definition recursive static items. + /// Allows the definition recursive static items. (accepted, static_recursion, "1.17.0", Some(29719), None), - // Allows `pub(restricted)` visibilities (RFC 1422). + /// Allows `pub(restricted)` visibilities (RFC 1422). (accepted, pub_restricted, "1.18.0", Some(32409), None), - // Allows `#![windows_subsystem]`. + /// Allows `#![windows_subsystem]`. (accepted, windows_subsystem, "1.18.0", Some(37499), None), - // Allows `break {expr}` with a value inside `loop`s. + /// Allows `break {expr}` with a value inside `loop`s. (accepted, loop_break_value, "1.19.0", Some(37339), None), - // Allows numeric fields in struct expressions and patterns. + /// Allows numeric fields in struct expressions and patterns. (accepted, relaxed_adts, "1.19.0", Some(35626), None), - // Allows coercing non capturing closures to function pointers. + /// Allows coercing non capturing closures to function pointers. (accepted, closure_to_fn_coercion, "1.19.0", Some(39817), None), - // Allows attributes on struct literal fields. + /// Allows attributes on struct literal fields. (accepted, struct_field_attributes, "1.20.0", Some(38814), None), - // Allows the definition of associated constants in `trait` or `impl` blocks. + /// Allows the definition of associated constants in `trait` or `impl` blocks. (accepted, associated_consts, "1.20.0", Some(29646), None), - // Allows usage of the `compile_error!` macro. + /// Allows usage of the `compile_error!` macro. (accepted, compile_error, "1.20.0", Some(40872), None), - // Allows code like `let x: &'static u32 = &42` to work (RFC 1414). + /// Allows code like `let x: &'static u32 = &42` to work (RFC 1414). (accepted, rvalue_static_promotion, "1.21.0", Some(38865), None), - // Allows `Drop` types in constants (RFC 1440). + /// Allows `Drop` types in constants (RFC 1440). (accepted, drop_types_in_const, "1.22.0", Some(33156), None), - // Allows the sysV64 ABI to be specified on all platforms - // instead of just the platforms on which it is the C ABI. + /// Allows the sysV64 ABI to be specified on all platforms + /// instead of just the platforms on which it is the C ABI. (accepted, abi_sysv64, "1.24.0", Some(36167), None), - // Allows `repr(align(16))` struct attribute (RFC 1358). + /// Allows `repr(align(16))` struct attribute (RFC 1358). (accepted, repr_align, "1.25.0", Some(33626), None), - // Allows '|' at beginning of match arms (RFC 1925). + /// Allows '|' at beginning of match arms (RFC 1925). (accepted, match_beginning_vert, "1.25.0", Some(44101), None), - // Allows nested groups in `use` items (RFC 2128). + /// Allows nested groups in `use` items (RFC 2128). (accepted, use_nested_groups, "1.25.0", Some(44494), None), - // Allows indexing into constant arrays. + /// Allows indexing into constant arrays. (accepted, const_indexing, "1.26.0", Some(29947), None), - // Allows using `a..=b` and `..=b` as inclusive range syntaxes. + /// Allows using `a..=b` and `..=b` as inclusive range syntaxes. (accepted, inclusive_range_syntax, "1.26.0", Some(28237), None), - // Allows `..=` in patterns (RFC 1192). + /// Allows `..=` in patterns (RFC 1192). (accepted, dotdoteq_in_patterns, "1.26.0", Some(28237), None), - // Allows `fn main()` with return types which implements `Termination` (RFC 1937). + /// Allows `fn main()` with return types which implements `Termination` (RFC 1937). (accepted, termination_trait, "1.26.0", Some(43301), None), - // Allows implementing `Clone` for closures where possible (RFC 2132). + /// Allows implementing `Clone` for closures where possible (RFC 2132). (accepted, clone_closures, "1.26.0", Some(44490), None), - // Allows implementing `Copy` for closures where possible (RFC 2132). + /// Allows implementing `Copy` for closures where possible (RFC 2132). (accepted, copy_closures, "1.26.0", Some(44490), None), - // Allows `impl Trait` in function arguments. + /// Allows `impl Trait` in function arguments. (accepted, universal_impl_trait, "1.26.0", Some(34511), None), - // Allows `impl Trait` in function return types. + /// Allows `impl Trait` in function return types. (accepted, conservative_impl_trait, "1.26.0", Some(34511), None), - // Allows using the `u128` and `i128` types. + /// Allows using the `u128` and `i128` types. (accepted, i128_type, "1.26.0", Some(35118), None), - // Allows default match binding modes (RFC 2005). + /// Allows default match binding modes (RFC 2005). (accepted, match_default_bindings, "1.26.0", Some(42640), None), - // Allows `'_` placeholder lifetimes. + /// Allows `'_` placeholder lifetimes. (accepted, underscore_lifetimes, "1.26.0", Some(44524), None), - // Allows attributes on lifetime/type formal parameters in generics (RFC 1327). + /// Allows attributes on lifetime/type formal parameters in generics (RFC 1327). (accepted, generic_param_attrs, "1.27.0", Some(48848), None), - // Allows `cfg(target_feature = "...")`. + /// Allows `cfg(target_feature = "...")`. (accepted, cfg_target_feature, "1.27.0", Some(29717), None), - // Allows `#[target_feature(...)]`. + /// Allows `#[target_feature(...)]`. (accepted, target_feature, "1.27.0", None, None), - // Allows using `dyn Trait` as a syntax for trait objects. + /// Allows using `dyn Trait` as a syntax for trait objects. (accepted, dyn_trait, "1.27.0", Some(44662), None), - // Allows `#[must_use]` on functions, and introduces must-use operators (RFC 1940). + /// Allows `#[must_use]` on functions, and introduces must-use operators (RFC 1940). (accepted, fn_must_use, "1.27.0", Some(43302), None), - // Allows use of the `:lifetime` macro fragment specifier. + /// Allows use of the `:lifetime` macro fragment specifier. (accepted, macro_lifetime_matcher, "1.27.0", Some(34303), None), - // Allows `#[test]` functions where the return type implements `Termination` (RFC 1937). + /// Allows `#[test]` functions where the return type implements `Termination` (RFC 1937). (accepted, termination_trait_test, "1.27.0", Some(48854), None), - // Allows the `#[global_allocator]` attribute. + /// Allows the `#[global_allocator]` attribute. (accepted, global_allocator, "1.28.0", Some(27389), None), - // Allows `#[repr(transparent)]` attribute on newtype structs. + /// Allows `#[repr(transparent)]` attribute on newtype structs. (accepted, repr_transparent, "1.28.0", Some(43036), None), - // Allows procedural macros in `proc-macro` crates. + /// Allows procedural macros in `proc-macro` crates. (accepted, proc_macro, "1.29.0", Some(38356), None), - // Allows `foo.rs` as an alternative to `foo/mod.rs`. + /// Allows `foo.rs` as an alternative to `foo/mod.rs`. (accepted, non_modrs_mods, "1.30.0", Some(44660), None), - // Allows use of the `:vis` macro fragment specifier + /// Allows use of the `:vis` macro fragment specifier (accepted, macro_vis_matcher, "1.30.0", Some(41022), None), - // Allows importing and reexporting macros with `use`, - // enables macro modularization in general. + /// Allows importing and reexporting macros with `use`, + /// enables macro modularization in general. (accepted, use_extern_macros, "1.30.0", Some(35896), None), - // Allows keywords to be escaped for use as identifiers. + /// Allows keywords to be escaped for use as identifiers. (accepted, raw_identifiers, "1.30.0", Some(48589), None), - // Allows attributes scoped to tools. + /// Allows attributes scoped to tools. (accepted, tool_attributes, "1.30.0", Some(44690), None), - // Allows multi-segment paths in attributes and derives. + /// Allows multi-segment paths in attributes and derives. (accepted, proc_macro_path_invoc, "1.30.0", Some(38356), None), - // Allows all literals in attribute lists and values of key-value pairs. + /// Allows all literals in attribute lists and values of key-value pairs. (accepted, attr_literals, "1.30.0", Some(34981), None), - // Allows inferring outlives requirements (RFC 2093). + /// Allows inferring outlives requirements (RFC 2093). (accepted, infer_outlives_requirements, "1.30.0", Some(44493), None), - // Allows annotating functions conforming to `fn(&PanicInfo) -> !` with `#[panic_handler]`. - // This defines the behavior of panics. + /// Allows annotating functions conforming to `fn(&PanicInfo) -> !` with `#[panic_handler]`. + /// This defines the behavior of panics. (accepted, panic_handler, "1.30.0", Some(44489), None), - // Allows `#[used]` to preserve symbols (see llvm.used). + /// Allows `#[used]` to preserve symbols (see llvm.used). (accepted, used, "1.30.0", Some(40289), None), - // Allows `crate` in paths. + /// Allows `crate` in paths. (accepted, crate_in_paths, "1.30.0", Some(45477), None), - // Allows resolving absolute paths as paths from other crates. + /// Allows resolving absolute paths as paths from other crates. (accepted, extern_absolute_paths, "1.30.0", Some(44660), None), - // Allows access to crate names passed via `--extern` through prelude. + /// Allows access to crate names passed via `--extern` through prelude. (accepted, extern_prelude, "1.30.0", Some(44660), None), - // Allows parentheses in patterns. + /// Allows parentheses in patterns. (accepted, pattern_parentheses, "1.31.0", Some(51087), None), - // Allows the definition of `const fn` functions. + /// Allows the definition of `const fn` functions. (accepted, min_const_fn, "1.31.0", Some(53555), None), - // Allows scoped lints. + /// Allows scoped lints. (accepted, tool_lints, "1.31.0", Some(44690), None), - // Allows lifetime elision in `impl` headers. For example: - // + `impl Iterator for &mut Iterator` - // + `impl Debug for Foo<'_>` + /// Allows lifetime elision in `impl` headers. For example: + /// + `impl Iterator for &mut Iterator` + /// + `impl Debug for Foo<'_>` (accepted, impl_header_lifetime_elision, "1.31.0", Some(15872), None), - // Allows `extern crate foo as bar;`. This puts `bar` into extern prelude. + /// Allows `extern crate foo as bar;`. This puts `bar` into extern prelude. (accepted, extern_crate_item_prelude, "1.31.0", Some(55599), None), - // Allows use of the `:literal` macro fragment specifier (RFC 1576). + /// Allows use of the `:literal` macro fragment specifier (RFC 1576). (accepted, macro_literal_matcher, "1.32.0", Some(35625), None), - // Allows use of `?` as the Kleene "at most one" operator in macros. + /// Allows use of `?` as the Kleene "at most one" operator in macros. (accepted, macro_at_most_once_rep, "1.32.0", Some(48075), None), - // Allows `Self` struct constructor (RFC 2302). + /// Allows `Self` struct constructor (RFC 2302). (accepted, self_struct_ctor, "1.32.0", Some(51994), None), - // Allows `Self` in type definitions (RFC 2300). + /// Allows `Self` in type definitions (RFC 2300). (accepted, self_in_typedefs, "1.32.0", Some(49303), None), - // Allows `use x::y;` to search `x` in the current scope. + /// Allows `use x::y;` to search `x` in the current scope. (accepted, uniform_paths, "1.32.0", Some(53130), None), - // Allows integer match exhaustiveness checking (RFC 2591). + /// Allows integer match exhaustiveness checking (RFC 2591). (accepted, exhaustive_integer_patterns, "1.33.0", Some(50907), None), - // Allows `use path as _;` and `extern crate c as _;`. + /// Allows `use path as _;` and `extern crate c as _;`. (accepted, underscore_imports, "1.33.0", Some(48216), None), - // Allows `#[repr(packed(N))]` attribute on structs. + /// Allows `#[repr(packed(N))]` attribute on structs. (accepted, repr_packed, "1.33.0", Some(33158), None), - // Allows irrefutable patterns in `if let` and `while let` statements (RFC 2086). + /// Allows irrefutable patterns in `if let` and `while let` statements (RFC 2086). (accepted, irrefutable_let_patterns, "1.33.0", Some(44495), None), - // Allows calling `const unsafe fn` inside `unsafe` blocks in `const fn` functions. + /// Allows calling `const unsafe fn` inside `unsafe` blocks in `const fn` functions. (accepted, min_const_unsafe_fn, "1.33.0", Some(55607), None), - // Allows let bindings, assignments and destructuring in `const` functions and constants. - // As long as control flow is not implemented in const eval, `&&` and `||` may not be used - // at the same time as let bindings. + /// Allows let bindings, assignments and destructuring in `const` functions and constants. + /// As long as control flow is not implemented in const eval, `&&` and `||` may not be used + /// at the same time as let bindings. (accepted, const_let, "1.33.0", Some(48821), None), - // Allows `#[cfg_attr(predicate, multiple, attributes, here)]`. + /// Allows `#[cfg_attr(predicate, multiple, attributes, here)]`. (accepted, cfg_attr_multi, "1.33.0", Some(54881), None), - // Allows top level or-patterns (`p | q`) in `if let` and `while let`. + /// Allows top level or-patterns (`p | q`) in `if let` and `while let`. (accepted, if_while_or_patterns, "1.33.0", Some(48215), None), - // Allows `cfg(target_vendor = "...")`. + /// Allows `cfg(target_vendor = "...")`. (accepted, cfg_target_vendor, "1.33.0", Some(29718), None), - // Allows `extern crate self as foo;`. - // This puts local crate root into extern prelude under name `foo`. + /// Allows `extern crate self as foo;`. + /// This puts local crate root into extern prelude under name `foo`. (accepted, extern_crate_self, "1.34.0", Some(56409), None), - // Allows arbitrary delimited token streams in non-macro attributes. + /// Allows arbitrary delimited token streams in non-macro attributes. (accepted, unrestricted_attribute_tokens, "1.34.0", Some(55208), None), - // Allows paths to enum variants on type aliases including `Self`. + /// Allows paths to enum variants on type aliases including `Self`. (accepted, type_alias_enum_variants, "1.37.0", Some(49683), None), - // Allows using `#[repr(align(X))]` on enums with equivalent semantics - // to wrapping an enum in a wrapper struct with `#[repr(align(X))]`. + /// Allows using `#[repr(align(X))]` on enums with equivalent semantics + /// to wrapping an enum in a wrapper struct with `#[repr(align(X))]`. (accepted, repr_align_enum, "1.37.0", Some(57996), None), - // Allows `const _: TYPE = VALUE`. + /// Allows `const _: TYPE = VALUE`. (accepted, underscore_const_names, "1.37.0", Some(54912), None), - // Allows free and inherent `async fn`s, `async` blocks, and `.await` expressions. + /// Allows free and inherent `async fn`s, `async` blocks, and `.await` expressions. (accepted, async_await, "1.39.0", Some(50547), None), // ------------------------------------------------------------------------- diff --git a/src/libsyntax/feature_gate/active.rs b/src/libsyntax/feature_gate/active.rs index 0bff4ed24a4ce..4008b79b141eb 100644 --- a/src/libsyntax/feature_gate/active.rs +++ b/src/libsyntax/feature_gate/active.rs @@ -3,6 +3,7 @@ use crate::edition::Edition; use crate::symbol::{Symbol, sym}; use syntax_pos::Span; +use super::{State, Feature}; macro_rules! set { ($field: ident) => {{ @@ -14,12 +15,24 @@ macro_rules! set { } macro_rules! declare_features { - ($((active, $feature: ident, $ver: expr, $issue: expr, $edition: expr),)+) => { + ($( + $(#[doc = $doc:tt])* (active, $feature:ident, $ver:expr, $issue:expr, $edition:expr), + )+) => { /// Represents active features that are currently being implemented or /// currently being considered for addition/removal. pub const ACTIVE_FEATURES: - &[(Symbol, &str, Option, Option, fn(&mut Features, Span))] = - &[$((sym::$feature, $ver, $issue, $edition, set!($feature))),+]; + &[Feature] = + &[$( + // (sym::$feature, $ver, $issue, $edition, set!($feature)) + Feature { + state: State::Active { set: set!($feature) }, + name: sym::$feature, + since: $ver, + issue: $issue, + edition: $edition, + description: concat!($($doc,)*), + } + ),+]; /// A set of features to be used by later passes. #[derive(Clone)] @@ -28,7 +41,10 @@ macro_rules! declare_features { pub declared_lang_features: Vec<(Symbol, Span, Option)>, /// `#![feature]` attrs for non-language (library) features pub declared_lib_features: Vec<(Symbol, Span)>, - $(pub $feature: bool),+ + $( + $(#[doc = $doc])* + pub $feature: bool + ),+ } impl Features { @@ -58,7 +74,7 @@ macro_rules! declare_features { // stable (active). // // Note that the features are grouped into internal/user-facing and then -// sorted by version inside those groups. This is inforced with tidy. +// sorted by version inside those groups. This is enforced with tidy. // // N.B., `tools/tidy/src/features.rs` parses this information directly out of the // source, so take care when modifying it. @@ -70,127 +86,127 @@ declare_features! ( // no-tracking-issue-start - // Allows using compiler's own crates. + /// Allows using compiler's own crates. (active, rustc_private, "1.0.0", Some(27812), None), - // Allows using the `rust-intrinsic`'s "ABI". + /// Allows using the `rust-intrinsic`'s "ABI". (active, intrinsics, "1.0.0", None, None), - // Allows using `#[lang = ".."]` attribute for linking items to special compiler logic. + /// Allows using `#[lang = ".."]` attribute for linking items to special compiler logic. (active, lang_items, "1.0.0", None, None), - // Allows using the `#[stable]` and `#[unstable]` attributes. + /// Allows using the `#[stable]` and `#[unstable]` attributes. (active, staged_api, "1.0.0", None, None), - // Allows using `#[allow_internal_unstable]`. This is an - // attribute on `macro_rules!` and can't use the attribute handling - // below (it has to be checked before expansion possibly makes - // macros disappear). + /// Allows using `#[allow_internal_unstable]`. This is an + /// attribute on `macro_rules!` and can't use the attribute handling + /// below (it has to be checked before expansion possibly makes + /// macros disappear). (active, allow_internal_unstable, "1.0.0", None, None), - // Allows using `#[allow_internal_unsafe]`. This is an - // attribute on `macro_rules!` and can't use the attribute handling - // below (it has to be checked before expansion possibly makes - // macros disappear). + /// Allows using `#[allow_internal_unsafe]`. This is an + /// attribute on `macro_rules!` and can't use the attribute handling + /// below (it has to be checked before expansion possibly makes + /// macros disappear). (active, allow_internal_unsafe, "1.0.0", None, None), - // Allows using the macros: - // + `__diagnostic_used` - // + `__register_diagnostic` - // +`__build_diagnostic_array` + /// Allows using the macros: + /// + `__diagnostic_used` + /// + `__register_diagnostic` + /// +`__build_diagnostic_array` (active, rustc_diagnostic_macros, "1.0.0", None, None), - // Allows using `#[rustc_const_unstable(feature = "foo", ..)]` which - // lets a function to be `const` when opted into with `#![feature(foo)]`. + /// Allows using `#[rustc_const_unstable(feature = "foo", ..)]` which + /// lets a function to be `const` when opted into with `#![feature(foo)]`. (active, rustc_const_unstable, "1.0.0", None, None), - // no-tracking-issue-end + /// no-tracking-issue-end - // Allows using `#[link_name="llvm.*"]`. + /// Allows using `#[link_name="llvm.*"]`. (active, link_llvm_intrinsics, "1.0.0", Some(29602), None), - // Allows using `rustc_*` attributes (RFC 572). + /// Allows using `rustc_*` attributes (RFC 572). (active, rustc_attrs, "1.0.0", Some(29642), None), - // Allows using `#[on_unimplemented(..)]` on traits. + /// Allows using `#[on_unimplemented(..)]` on traits. (active, on_unimplemented, "1.0.0", Some(29628), None), - // Allows using the `box $expr` syntax. + /// Allows using the `box $expr` syntax. (active, box_syntax, "1.0.0", Some(49733), None), - // Allows using `#[main]` to replace the entrypoint `#[lang = "start"]` calls. + /// Allows using `#[main]` to replace the entrypoint `#[lang = "start"]` calls. (active, main, "1.0.0", Some(29634), None), - // Allows using `#[start]` on a function indicating that it is the program entrypoint. + /// Allows using `#[start]` on a function indicating that it is the program entrypoint. (active, start, "1.0.0", Some(29633), None), - // Allows using the `#[fundamental]` attribute. + /// Allows using the `#[fundamental]` attribute. (active, fundamental, "1.0.0", Some(29635), None), - // Allows using the `rust-call` ABI. + /// Allows using the `rust-call` ABI. (active, unboxed_closures, "1.0.0", Some(29625), None), - // Allows using the `#[linkage = ".."]` attribute. + /// Allows using the `#[linkage = ".."]` attribute. (active, linkage, "1.0.0", Some(29603), None), - // Allows features specific to OIBIT (auto traits). + /// Allows features specific to OIBIT (auto traits). (active, optin_builtin_traits, "1.0.0", Some(13231), None), - // Allows using `box` in patterns (RFC 469). + /// Allows using `box` in patterns (RFC 469). (active, box_patterns, "1.0.0", Some(29641), None), // no-tracking-issue-start - // Allows using `#[prelude_import]` on glob `use` items. + /// Allows using `#[prelude_import]` on glob `use` items. (active, prelude_import, "1.2.0", None, None), // no-tracking-issue-end // no-tracking-issue-start - // Allows using `#[omit_gdb_pretty_printer_section]`. + /// Allows using `#[omit_gdb_pretty_printer_section]`. (active, omit_gdb_pretty_printer_section, "1.5.0", None, None), - // Allows using the `vectorcall` ABI. + /// Allows using the `vectorcall` ABI. (active, abi_vectorcall, "1.7.0", None, None), // no-tracking-issue-end - // Allows using `#[structural_match]` which indicates that a type is structurally matchable. + /// Allows using `#[structural_match]` which indicates that a type is structurally matchable. (active, structural_match, "1.8.0", Some(31434), None), - // Allows using the `may_dangle` attribute (RFC 1327). + /// Allows using the `may_dangle` attribute (RFC 1327). (active, dropck_eyepatch, "1.10.0", Some(34761), None), - // Allows using the `#![panic_runtime]` attribute. + /// Allows using the `#![panic_runtime]` attribute. (active, panic_runtime, "1.10.0", Some(32837), None), - // Allows declaring with `#![needs_panic_runtime]` that a panic runtime is needed. + /// Allows declaring with `#![needs_panic_runtime]` that a panic runtime is needed. (active, needs_panic_runtime, "1.10.0", Some(32837), None), // no-tracking-issue-start - // Allows identifying the `compiler_builtins` crate. + /// Allows identifying the `compiler_builtins` crate. (active, compiler_builtins, "1.13.0", None, None), - // Allows using the `unadjusted` ABI; perma-unstable. + /// Allows using the `unadjusted` ABI; perma-unstable. (active, abi_unadjusted, "1.16.0", None, None), - // Allows identifying crates that contain sanitizer runtimes. + /// Allows identifying crates that contain sanitizer runtimes. (active, sanitizer_runtime, "1.17.0", None, None), - // Used to identify crates that contain the profiler runtime. + /// Used to identify crates that contain the profiler runtime. (active, profiler_runtime, "1.18.0", None, None), - // Allows using the `thiscall` ABI. + /// Allows using the `thiscall` ABI. (active, abi_thiscall, "1.19.0", None, None), - // Allows using `#![needs_allocator]`, an implementation detail of `#[global_allocator]`. + /// Allows using `#![needs_allocator]`, an implementation detail of `#[global_allocator]`. (active, allocator_internals, "1.20.0", None, None), // no-tracking-issue-end - // Added for testing E0705; perma-unstable. + /// Added for testing E0705; perma-unstable. (active, test_2018_feature, "1.31.0", Some(0), Some(Edition::Edition2018)), // ------------------------------------------------------------------------- @@ -228,281 +244,282 @@ declare_features! ( // feature-group-start: actual feature gates // ------------------------------------------------------------------------- - // Allows using the `#[link_args]` attribute. + /// Allows using the `#[link_args]` attribute. (active, link_args, "1.0.0", Some(29596), None), - // Allows defining identifiers beyond ASCII. + /// Allows defining identifiers beyond ASCII. (active, non_ascii_idents, "1.0.0", Some(55467), None), - // Allows using `#[plugin_registrar]` on functions. + /// Allows using `#[plugin_registrar]` on functions. (active, plugin_registrar, "1.0.0", Some(29597), None), - // Allows using `#![plugin(myplugin)]`. + /// Allows using `#![plugin(myplugin)]`. (active, plugin, "1.0.0", Some(29597), None), - // Allows using `#[thread_local]` on `static` items. + /// Allows using `#[thread_local]` on `static` items. (active, thread_local, "1.0.0", Some(29594), None), - // Allows the use of SIMD types in functions declared in `extern` blocks. + /// Allows the use of SIMD types in functions declared in `extern` blocks. (active, simd_ffi, "1.0.0", Some(27731), None), - // Allows using custom attributes (RFC 572). + /// Allows using custom attributes (RFC 572). (active, custom_attribute, "1.0.0", Some(29642), None), - // Allows using non lexical lifetimes (RFC 2094). + /// Allows using non lexical lifetimes (RFC 2094). (active, nll, "1.0.0", Some(43234), None), - // Allows using slice patterns. + /// Allows using slice patterns. (active, slice_patterns, "1.0.0", Some(62254), None), - // Allows the definition of `const` functions with some advanced features. + /// Allows the definition of `const` functions with some advanced features. (active, const_fn, "1.2.0", Some(57563), None), - // Allows associated type defaults. + /// Allows associated type defaults. (active, associated_type_defaults, "1.2.0", Some(29661), None), - // Allows `#![no_core]`. + /// Allows `#![no_core]`. (active, no_core, "1.3.0", Some(29639), None), - // Allows default type parameters to influence type inference. + /// Allows default type parameters to influence type inference. (active, default_type_parameter_fallback, "1.3.0", Some(27336), None), - // Allows `repr(simd)` and importing the various simd intrinsics. + /// Allows `repr(simd)` and importing the various simd intrinsics. (active, repr_simd, "1.4.0", Some(27731), None), - // Allows `extern "platform-intrinsic" { ... }`. + /// Allows `extern "platform-intrinsic" { ... }`. (active, platform_intrinsics, "1.4.0", Some(27731), None), - // Allows `#[unwind(..)]`. - // - // Permits specifying whether a function should permit unwinding or abort on unwind. + /// Allows `#[unwind(..)]`. + /// + /// Permits specifying whether a function should permit unwinding or abort on unwind. (active, unwind_attributes, "1.4.0", Some(58760), None), - // Allows `#[no_debug]`. + /// Allows `#[no_debug]`. (active, no_debug, "1.5.0", Some(29721), None), - // Allows attributes on expressions and non-item statements. + /// Allows attributes on expressions and non-item statements. (active, stmt_expr_attributes, "1.6.0", Some(15701), None), - // Allows the use of type ascription in expressions. + /// Allows the use of type ascription in expressions. (active, type_ascription, "1.6.0", Some(23416), None), - // Allows `cfg(target_thread_local)`. + /// Allows `cfg(target_thread_local)`. (active, cfg_target_thread_local, "1.7.0", Some(29594), None), - // Allows specialization of implementations (RFC 1210). + /// Allows specialization of implementations (RFC 1210). (active, specialization, "1.7.0", Some(31844), None), - // Allows using `#[naked]` on functions. + /// Allows using `#[naked]` on functions. (active, naked_functions, "1.9.0", Some(32408), None), - // Allows `cfg(target_has_atomic = "...")`. + /// Allows `cfg(target_has_atomic = "...")`. (active, cfg_target_has_atomic, "1.9.0", Some(32976), None), - // Allows `X..Y` patterns. + /// Allows `X..Y` patterns. (active, exclusive_range_pattern, "1.11.0", Some(37854), None), - // Allows the `!` type. Does not imply 'exhaustive_patterns' (below) any more. + /// Allows the `!` type. Does not imply 'exhaustive_patterns' (below) any more. (active, never_type, "1.13.0", Some(35121), None), - // Allows exhaustive pattern matching on types that contain uninhabited types. + /// Allows exhaustive pattern matching on types that contain uninhabited types. (active, exhaustive_patterns, "1.13.0", Some(51085), None), - // Allows untagged unions `union U { ... }`. + /// Allows untagged unions `union U { ... }`. (active, untagged_unions, "1.13.0", Some(32836), None), - // Allows `#[link(..., cfg(..))]`. + /// Allows `#[link(..., cfg(..))]`. (active, link_cfg, "1.14.0", Some(37406), None), - // Allows `extern "ptx-*" fn()`. + /// Allows `extern "ptx-*" fn()`. (active, abi_ptx, "1.15.0", Some(38788), None), - // Allows the `#[repr(i128)]` attribute for enums. + /// Allows the `#[repr(i128)]` attribute for enums. (active, repr128, "1.16.0", Some(35118), None), - // Allows `#[link(kind="static-nobundle"...)]`. + /// Allows `#[link(kind="static-nobundle"...)]`. (active, static_nobundle, "1.16.0", Some(37403), None), - // Allows `extern "msp430-interrupt" fn()`. + /// Allows `extern "msp430-interrupt" fn()`. (active, abi_msp430_interrupt, "1.16.0", Some(38487), None), - // Allows declarative macros 2.0 (`macro`). + /// Allows declarative macros 2.0 (`macro`). (active, decl_macro, "1.17.0", Some(39412), None), - // Allows `extern "x86-interrupt" fn()`. + /// Allows `extern "x86-interrupt" fn()`. (active, abi_x86_interrupt, "1.17.0", Some(40180), None), - // Allows overlapping impls of marker traits. + /// Allows overlapping impls of marker traits. (active, overlapping_marker_traits, "1.18.0", Some(29864), None), - // Allows a test to fail without failing the whole suite. + /// Allows a test to fail without failing the whole suite. (active, allow_fail, "1.19.0", Some(46488), None), - // Allows unsized tuple coercion. + /// Allows unsized tuple coercion. (active, unsized_tuple_coercion, "1.20.0", Some(42877), None), - // Allows defining generators. + /// Allows defining generators. (active, generators, "1.21.0", Some(43122), None), - // Allows `#[doc(cfg(...))]`. + /// Allows `#[doc(cfg(...))]`. (active, doc_cfg, "1.21.0", Some(43781), None), - // Allows `#[doc(masked)]`. + /// Allows `#[doc(masked)]`. (active, doc_masked, "1.21.0", Some(44027), None), - // Allows `#[doc(spotlight)]`. + /// Allows `#[doc(spotlight)]`. (active, doc_spotlight, "1.22.0", Some(45040), None), - // Allows `#[doc(include = "some-file")]`. + /// Allows `#[doc(include = "some-file")]`. (active, external_doc, "1.22.0", Some(44732), None), - // Allows future-proofing enums/structs with the `#[non_exhaustive]` attribute (RFC 2008). + /// Allows future-proofing enums/structs with the `#[non_exhaustive]` attribute (RFC 2008). (active, non_exhaustive, "1.22.0", Some(44109), None), - // Allows using `crate` as visibility modifier, synonymous with `pub(crate)`. + /// Allows using `crate` as visibility modifier, synonymous with `pub(crate)`. (active, crate_visibility_modifier, "1.23.0", Some(53120), None), - // Allows defining `extern type`s. + /// Allows defining `extern type`s. (active, extern_types, "1.23.0", Some(43467), None), - // Allows trait methods with arbitrary self types. + /// Allows trait methods with arbitrary self types. (active, arbitrary_self_types, "1.23.0", Some(44874), None), - // Allows in-band quantification of lifetime bindings (e.g., `fn foo(x: &'a u8) -> &'a u8`). + /// Allows in-band quantification of lifetime bindings (e.g., `fn foo(x: &'a u8) -> &'a u8`). (active, in_band_lifetimes, "1.23.0", Some(44524), None), - // Allows associated types to be generic, e.g., `type Foo;` (RFC 1598). + /// Allows associated types to be generic, e.g., `type Foo;` (RFC 1598). (active, generic_associated_types, "1.23.0", Some(44265), None), - // Allows defining `trait X = A + B;` alias items. + /// Allows defining `trait X = A + B;` alias items. (active, trait_alias, "1.24.0", Some(41517), None), - // Allows infering `'static` outlives requirements (RFC 2093). + /// Allows infering `'static` outlives requirements (RFC 2093). (active, infer_static_outlives_requirements, "1.26.0", Some(54185), None), - // Allows macro invocations in `extern {}` blocks. + /// Allows macro invocations in `extern {}` blocks. (active, macros_in_extern, "1.27.0", Some(49476), None), - // Allows accessing fields of unions inside `const` functions. + /// Allows accessing fields of unions inside `const` functions. (active, const_fn_union, "1.27.0", Some(51909), None), - // Allows casting raw pointers to `usize` during const eval. + /// Allows casting raw pointers to `usize` during const eval. (active, const_raw_ptr_to_usize_cast, "1.27.0", Some(51910), None), - // Allows dereferencing raw pointers during const eval. + /// Allows dereferencing raw pointers during const eval. (active, const_raw_ptr_deref, "1.27.0", Some(51911), None), - // Allows comparing raw pointers during const eval. + /// Allows comparing raw pointers during const eval. (active, const_compare_raw_pointers, "1.27.0", Some(53020), None), - // Allows `#[doc(alias = "...")]`. + /// Allows `#[doc(alias = "...")]`. (active, doc_alias, "1.27.0", Some(50146), None), - // Allows inconsistent bounds in where clauses. + /// Allows inconsistent bounds in where clauses. (active, trivial_bounds, "1.28.0", Some(48214), None), - // Allows `'a: { break 'a; }`. + /// Allows `'a: { break 'a; }`. (active, label_break_value, "1.28.0", Some(48594), None), - // Allows using `#[doc(keyword = "...")]`. + /// Allows using `#[doc(keyword = "...")]`. (active, doc_keyword, "1.28.0", Some(51315), None), - // Allows reinterpretation of the bits of a value of one type as another type during const eval. + /// Allows reinterpretation of the bits of a value of one type as another + /// type during const eval. (active, const_transmute, "1.29.0", Some(53605), None), - // Allows using `try {...}` expressions. + /// Allows using `try {...}` expressions. (active, try_blocks, "1.29.0", Some(31436), None), - // Allows defining an `#[alloc_error_handler]`. + /// Allows defining an `#[alloc_error_handler]`. (active, alloc_error_handler, "1.29.0", Some(51540), None), - // Allows using the `amdgpu-kernel` ABI. + /// Allows using the `amdgpu-kernel` ABI. (active, abi_amdgpu_kernel, "1.29.0", Some(51575), None), - // Allows panicking during const eval (producing compile-time errors). + /// Allows panicking during const eval (producing compile-time errors). (active, const_panic, "1.30.0", Some(51999), None), - // Allows `#[marker]` on certain traits allowing overlapping implementations. + /// Allows `#[marker]` on certain traits allowing overlapping implementations. (active, marker_trait_attr, "1.30.0", Some(29864), None), - // Allows macro invocations on modules expressions and statements and - // procedural macros to expand to non-items. + /// Allows macro invocations on modules expressions and statements and + /// procedural macros to expand to non-items. (active, proc_macro_hygiene, "1.30.0", Some(54727), None), - // Allows unsized rvalues at arguments and parameters. + /// Allows unsized rvalues at arguments and parameters. (active, unsized_locals, "1.30.0", Some(48055), None), - // Allows custom test frameworks with `#![test_runner]` and `#[test_case]`. + /// Allows custom test frameworks with `#![test_runner]` and `#[test_case]`. (active, custom_test_frameworks, "1.30.0", Some(50297), None), - // Allows non-builtin attributes in inner attribute position. + /// Allows non-builtin attributes in inner attribute position. (active, custom_inner_attributes, "1.30.0", Some(54726), None), - // Allows mixing bind-by-move in patterns and references to those identifiers in guards. + /// Allows mixing bind-by-move in patterns and references to those identifiers in guards. (active, bind_by_move_pattern_guards, "1.30.0", Some(15287), None), - // Allows `impl Trait` in bindings (`let`, `const`, `static`). + /// Allows `impl Trait` in bindings (`let`, `const`, `static`). (active, impl_trait_in_bindings, "1.30.0", Some(63065), None), - // Allows using `reason` in lint attributes and the `#[expect(lint)]` lint check. + /// Allows using `reason` in lint attributes and the `#[expect(lint)]` lint check. (active, lint_reasons, "1.31.0", Some(54503), None), - // Allows exhaustive integer pattern matching on `usize` and `isize`. + /// Allows exhaustive integer pattern matching on `usize` and `isize`. (active, precise_pointer_size_matching, "1.32.0", Some(56354), None), - // Allows relaxing the coherence rules such that - // `impl ForeignTrait for ForeignType is permitted. + /// Allows relaxing the coherence rules such that + /// `impl ForeignTrait for ForeignType is permitted. (active, re_rebalance_coherence, "1.32.0", Some(55437), None), - // Allows using `#[ffi_returns_twice]` on foreign functions. + /// Allows using `#[ffi_returns_twice]` on foreign functions. (active, ffi_returns_twice, "1.34.0", Some(58314), None), - // Allows const generic types (e.g. `struct Foo(...);`). + /// Allows const generic types (e.g. `struct Foo(...);`). (active, const_generics, "1.34.0", Some(44580), None), - // Allows using `#[optimize(X)]`. + /// Allows using `#[optimize(X)]`. (active, optimize_attribute, "1.34.0", Some(54882), None), - // Allows using C-variadics. + /// Allows using C-variadics. (active, c_variadic, "1.34.0", Some(44930), None), - // Allows the user of associated type bounds. + /// Allows the user of associated type bounds. (active, associated_type_bounds, "1.34.0", Some(52662), None), - // Attributes on formal function params. + /// Attributes on formal function params. (active, param_attrs, "1.36.0", Some(60406), None), - // Allows calling constructor functions in `const fn`. + /// Allows calling constructor functions in `const fn`. (active, const_constructor, "1.37.0", Some(61456), None), - // Allows `if/while p && let q = r && ...` chains. + /// Allows `if/while p && let q = r && ...` chains. (active, let_chains, "1.37.0", Some(53667), None), - // Allows #[repr(transparent)] on enums (RFC 2645). + /// Allows #[repr(transparent)] on enums (RFC 2645). (active, transparent_enums, "1.37.0", Some(60405), None), - // Allows #[repr(transparent)] on unions (RFC 2645). + /// Allows #[repr(transparent)] on unions (RFC 2645). (active, transparent_unions, "1.37.0", Some(60405), None), - // Allows explicit discriminants on non-unit enum variants. + /// Allows explicit discriminants on non-unit enum variants. (active, arbitrary_enum_discriminant, "1.37.0", Some(60553), None), - // Allows `impl Trait` with multiple unrelated lifetimes. + /// Allows `impl Trait` with multiple unrelated lifetimes. (active, member_constraints, "1.37.0", Some(61977), None), - // Allows `async || body` closures. + /// Allows `async || body` closures. (active, async_closure, "1.37.0", Some(62290), None), - // Allows the use of `#[cfg(doctest)]`, set when rustdoc is collecting doctests + /// Allows the use of `#[cfg(doctest)]`, set when rustdoc is collecting doctests (active, cfg_doctest, "1.37.0", Some(62210), None), - // Allows `[x; N]` where `x` is a constant (RFC 2203). + /// Allows `[x; N]` where `x` is a constant (RFC 2203). (active, const_in_array_repeat_expressions, "1.37.0", Some(49147), None), - // Allows `impl Trait` to be used inside type aliases (RFC 2515). + /// Allows `impl Trait` to be used inside type aliases (RFC 2515). (active, type_alias_impl_trait, "1.38.0", Some(63063), None), - // Allows the use of or-patterns, e.g. `0 | 1`. + /// Allows the use of or-patterns, e.g. `0 | 1`. (active, or_patterns, "1.38.0", Some(54883), None), // ------------------------------------------------------------------------- diff --git a/src/libsyntax/feature_gate/removed.rs b/src/libsyntax/feature_gate/removed.rs index 6ebfeb29f677b..6494c82e1228b 100644 --- a/src/libsyntax/feature_gate/removed.rs +++ b/src/libsyntax/feature_gate/removed.rs @@ -3,14 +3,18 @@ use crate::symbol::{Symbol, sym}; macro_rules! declare_features { - ($((removed, $feature: ident, $ver: expr, $issue: expr, None, $reason: expr),)+) => { + ($( + $(#[doc = $doc:tt])* (removed, $feature:ident, $ver:expr, $issue:expr, None, $reason:expr), + )+) => { /// Represents unstable features which have since been removed (it was once Active) pub const REMOVED_FEATURES: &[(Symbol, &str, Option, Option<&str>)] = &[ $((sym::$feature, $ver, $issue, $reason)),+ ]; }; - ($((stable_removed, $feature: ident, $ver: expr, $issue: expr, None),)+) => { + ($( + $(#[doc = $doc:tt])* (stable_removed, $feature:ident, $ver:expr, $issue:expr, None), + )+) => { /// Represents stable features which have since been removed (it was once Accepted) pub const STABLE_REMOVED_FEATURES: &[(Symbol, &str, Option, Option<&str>)] = &[ $((sym::$feature, $ver, $issue, None)),+ @@ -25,17 +29,17 @@ declare_features! ( (removed, import_shadowing, "1.0.0", None, None, None), (removed, managed_boxes, "1.0.0", None, None, None), - // Allows use of unary negate on unsigned integers, e.g., -e for e: u8 + /// Allows use of unary negate on unsigned integers, e.g., -e for e: u8 (removed, negate_unsigned, "1.0.0", Some(29645), None, None), (removed, reflect, "1.0.0", Some(27749), None, None), - // A way to temporarily opt out of opt in copy. This will *never* be accepted. + /// A way to temporarily opt out of opt in copy. This will *never* be accepted. (removed, opt_out_copy, "1.0.0", None, None, None), (removed, quad_precision_float, "1.0.0", None, None, None), (removed, struct_inherit, "1.0.0", None, None, None), (removed, test_removed_feature, "1.0.0", None, None, None), (removed, visible_private_types, "1.0.0", None, None, None), (removed, unsafe_no_drop_flag, "1.0.0", None, None, None), - // Allows using items which are missing stability attributes + /// Allows using items which are missing stability attributes (removed, unmarked_api, "1.0.0", None, None, None), (removed, allocator, "1.0.0", None, None, None), (removed, simd, "1.0.0", Some(27731), None, @@ -57,18 +61,18 @@ declare_features! ( Some("subsumed by `#![feature(proc_macro_hygiene)]`")), (removed, panic_implementation, "1.28.0", Some(44489), None, Some("subsumed by `#[panic_handler]`")), - // Allows the use of `#[derive(Anything)]` as sugar for `#[derive_Anything]`. + /// Allows the use of `#[derive(Anything)]` as sugar for `#[derive_Anything]`. (removed, custom_derive, "1.32.0", Some(29644), None, Some("subsumed by `#[proc_macro_derive]`")), - // Paths of the form: `extern::foo::bar` + /// Paths of the form: `extern::foo::bar` (removed, extern_in_paths, "1.33.0", Some(55600), None, Some("subsumed by `::foo::bar` paths")), (removed, quote, "1.33.0", Some(29601), None, None), - // Allows using `#[unsafe_destructor_blind_to_params]` (RFC 1238). + /// Allows using `#[unsafe_destructor_blind_to_params]` (RFC 1238). (removed, dropck_parametricity, "1.38.0", Some(28498), None, None), (removed, await_macro, "1.38.0", Some(50547), None, Some("subsumed by `.await` syntax")), - // Allows defining `existential type`s. + /// Allows defining `existential type`s. (removed, existential_type, "1.38.0", Some(63063), None, Some("removed in favor of `#![feature(type_alias_impl_trait)]`")), From c9d9616e825fecd4301beaf7bcd9115d5d7d393f Mon Sep 17 00:00:00 2001 From: Pascal Hertleif Date: Sat, 24 Aug 2019 17:50:21 +0200 Subject: [PATCH 3/4] Introduce and use `Feature` type for feature gates This replaces the ad-hoc tuples used in the different feature gate files and unifies their content into a common type, leading to more readable matches and other good stuff that comes from having named fields. It also contains the description of each feature as extracted from the doc comment. --- src/libsyntax/feature_gate/accepted.rs | 16 ++++++++++--- src/libsyntax/feature_gate/active.rs | 10 ++++++++ src/libsyntax/feature_gate/check.rs | 33 ++++++++++++++------------ src/libsyntax/feature_gate/mod.rs | 33 ++++++++++++++++++++++++++ src/libsyntax/feature_gate/removed.rs | 29 ++++++++++++++++++---- 5 files changed, 98 insertions(+), 23 deletions(-) diff --git a/src/libsyntax/feature_gate/accepted.rs b/src/libsyntax/feature_gate/accepted.rs index 28e4d2c073c7c..6c0b271c6c5e9 100644 --- a/src/libsyntax/feature_gate/accepted.rs +++ b/src/libsyntax/feature_gate/accepted.rs @@ -1,14 +1,24 @@ //! List of the accepted feature gates. -use crate::symbol::{Symbol, sym}; +use crate::symbol::sym; +use super::{State, Feature}; macro_rules! declare_features { ($( $(#[doc = $doc:tt])* (accepted, $feature:ident, $ver:expr, $issue:expr, None), )+) => { /// Those language feature has since been Accepted (it was once Active) - pub const ACCEPTED_FEATURES: &[(Symbol, &str, Option, Option<&str>)] = &[ - $((sym::$feature, $ver, $issue, None)),+ + pub const ACCEPTED_FEATURES: &[Feature] = &[ + $( + Feature { + state: State::Accepted, + name: sym::$feature, + since: $ver, + issue: $issue, + edition: None, + description: concat!($($doc,)*), + } + ),+ ]; } } diff --git a/src/libsyntax/feature_gate/active.rs b/src/libsyntax/feature_gate/active.rs index 4008b79b141eb..c947b09fdcb57 100644 --- a/src/libsyntax/feature_gate/active.rs +++ b/src/libsyntax/feature_gate/active.rs @@ -65,6 +65,16 @@ macro_rules! declare_features { }; } +impl Feature { + /// Set this feature in `Features`. Panics if called on a non-active feature. + pub fn set(&self, features: &mut Features, span: Span) { + match self.state { + State::Active { set } => set(features, span), + _ => panic!("Called `set` on feature `{}` which is not `active`", self.name) + } + } +} + // If you change this, please modify `src/doc/unstable-book` as well. // // Don't ever remove anything from this list; move them to `removed.rs`. diff --git a/src/libsyntax/feature_gate/check.rs b/src/libsyntax/feature_gate/check.rs index d82b287b6fb05..344e5fd6e46c2 100644 --- a/src/libsyntax/feature_gate/check.rs +++ b/src/libsyntax/feature_gate/check.rs @@ -1,4 +1,4 @@ -use super::active::{ACTIVE_FEATURES, Features}; +use super::{active::{ACTIVE_FEATURES, Features}, Feature, State as FeatureState}; use super::accepted::ACCEPTED_FEATURES; use super::removed::{REMOVED_FEATURES, STABLE_REMOVED_FEATURES}; use super::builtin_attrs::{AttributeGate, AttributeType, BuiltinAttribute, BUILTIN_ATTRIBUTE_MAP}; @@ -127,17 +127,16 @@ pub fn check_attribute(attr: &ast::Attribute, parse_sess: &ParseSess, features: } fn find_lang_feature_issue(feature: Symbol) -> Option { - if let Some(info) = ACTIVE_FEATURES.iter().find(|t| t.0 == feature) { - let issue = info.2; + if let Some(info) = ACTIVE_FEATURES.iter().find(|t| t.name == feature) { // FIXME (#28244): enforce that active features have issue numbers - // assert!(issue.is_some()) - issue + // assert!(info.issue.is_some()) + info.issue } else { // search in Accepted, Removed, or Stable Removed features let found = ACCEPTED_FEATURES.iter().chain(REMOVED_FEATURES).chain(STABLE_REMOVED_FEATURES) - .find(|t| t.0 == feature); + .find(|t| t.name == feature); match found { - Some(&(_, _, issue, _)) => issue, + Some(&Feature { issue, .. }) => issue, None => panic!("Feature `{}` is not declared anywhere", feature), } } @@ -829,14 +828,18 @@ pub fn get_features(span_handler: &Handler, krate_attrs: &[ast::Attribute], continue; } - let removed = REMOVED_FEATURES.iter().find(|f| name == f.0); - let stable_removed = STABLE_REMOVED_FEATURES.iter().find(|f| name == f.0); - if let Some((.., reason)) = removed.or(stable_removed) { - feature_removed(span_handler, mi.span(), *reason); - continue; + let removed = REMOVED_FEATURES.iter().find(|f| name == f.name); + let stable_removed = STABLE_REMOVED_FEATURES.iter().find(|f| name == f.name); + if let Some(Feature { state, .. }) = removed.or(stable_removed) { + if let FeatureState::Removed { reason } + | FeatureState::Stabilized { reason } = state + { + feature_removed(span_handler, mi.span(), *reason); + continue; + } } - if let Some((_, since, ..)) = ACCEPTED_FEATURES.iter().find(|f| name == f.0) { + if let Some(Feature { since, .. }) = ACCEPTED_FEATURES.iter().find(|f| name == f.name) { let since = Some(Symbol::intern(since)); features.declared_lang_features.push((name, mi.span(), since)); continue; @@ -851,8 +854,8 @@ pub fn get_features(span_handler: &Handler, krate_attrs: &[ast::Attribute], } } - if let Some((.., set)) = ACTIVE_FEATURES.iter().find(|f| name == f.0) { - set(&mut features, mi.span()); + if let Some(f) = ACTIVE_FEATURES.iter().find(|f| name == f.name) { + f.set(&mut features, mi.span()); features.declared_lang_features.push((name, mi.span(), None)); continue; } diff --git a/src/libsyntax/feature_gate/mod.rs b/src/libsyntax/feature_gate/mod.rs index 97793bca1f589..1e41667ea411e 100644 --- a/src/libsyntax/feature_gate/mod.rs +++ b/src/libsyntax/feature_gate/mod.rs @@ -18,6 +18,39 @@ mod active; mod builtin_attrs; mod check; +use std::fmt; +use crate::{edition::Edition, symbol::Symbol}; +use syntax_pos::Span; + +#[derive(Clone, Copy)] +pub enum State { + Accepted, + Active { set: fn(&mut Features, Span) }, + Removed { reason: Option<&'static str> }, + Stabilized { reason: Option<&'static str> }, +} + +impl fmt::Debug for State { + fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result { + match self { + State::Accepted { .. } => write!(f, "accepted"), + State::Active { .. } => write!(f, "active"), + State::Removed { .. } => write!(f, "removed"), + State::Stabilized { .. } => write!(f, "stabilized"), + } + } +} + +#[derive(Debug, Clone)] +pub struct Feature { + state: State, + name: Symbol, + since: &'static str, + issue: Option, + edition: Option, + description: &'static str, +} + pub use active::{Features, INCOMPLETE_FEATURES}; pub use builtin_attrs::{ AttributeGate, AttributeType, GatedCfg, diff --git a/src/libsyntax/feature_gate/removed.rs b/src/libsyntax/feature_gate/removed.rs index 6494c82e1228b..ad7d69b3e7372 100644 --- a/src/libsyntax/feature_gate/removed.rs +++ b/src/libsyntax/feature_gate/removed.rs @@ -1,14 +1,24 @@ //! List of the removed feature gates. -use crate::symbol::{Symbol, sym}; +use crate::symbol::sym; +use super::{State, Feature}; macro_rules! declare_features { ($( $(#[doc = $doc:tt])* (removed, $feature:ident, $ver:expr, $issue:expr, None, $reason:expr), )+) => { /// Represents unstable features which have since been removed (it was once Active) - pub const REMOVED_FEATURES: &[(Symbol, &str, Option, Option<&str>)] = &[ - $((sym::$feature, $ver, $issue, $reason)),+ + pub const REMOVED_FEATURES: &[Feature] = &[ + $( + Feature { + state: State::Removed { reason: $reason }, + name: sym::$feature, + since: $ver, + issue: $issue, + edition: None, + description: concat!($($doc,)*), + } + ),+ ]; }; @@ -16,8 +26,17 @@ macro_rules! declare_features { $(#[doc = $doc:tt])* (stable_removed, $feature:ident, $ver:expr, $issue:expr, None), )+) => { /// Represents stable features which have since been removed (it was once Accepted) - pub const STABLE_REMOVED_FEATURES: &[(Symbol, &str, Option, Option<&str>)] = &[ - $((sym::$feature, $ver, $issue, None)),+ + pub const STABLE_REMOVED_FEATURES: &[Feature] = &[ + $( + Feature { + state: State::Stabilized { reason: None }, + name: sym::$feature, + since: $ver, + issue: $issue, + edition: None, + description: concat!($($doc,)*), + } + ),+ ]; }; } From 94e8ff4f0b94c788ec9e9a28d3aa6f87062e2966 Mon Sep 17 00:00:00 2001 From: Pascal Hertleif Date: Sat, 24 Aug 2019 17:50:21 +0200 Subject: [PATCH 4/4] Refactor feature gate checking code Tries to clarify the filtering of active features and make the code more expressive. --- src/libsyntax/feature_gate/check.rs | 40 ++++++++++++++++------------- 1 file changed, 22 insertions(+), 18 deletions(-) diff --git a/src/libsyntax/feature_gate/check.rs b/src/libsyntax/feature_gate/check.rs index 344e5fd6e46c2..f3a9d135125ae 100644 --- a/src/libsyntax/feature_gate/check.rs +++ b/src/libsyntax/feature_gate/check.rs @@ -732,13 +732,9 @@ pub fn get_features(span_handler: &Handler, krate_attrs: &[ast::Attribute], } } - for &(name, .., f_edition, set) in ACTIVE_FEATURES { - if let Some(f_edition) = f_edition { - if f_edition <= crate_edition { - set(&mut features, DUMMY_SP); - edition_enabled_features.insert(name, crate_edition); - } - } + for feature in active_features_up_to(crate_edition) { + feature.set(&mut features, DUMMY_SP); + edition_enabled_features.insert(feature.name, crate_edition); } // Process the edition umbrella feature-gates first, to ensure @@ -760,20 +756,17 @@ pub fn get_features(span_handler: &Handler, krate_attrs: &[ast::Attribute], let name = mi.name_or_empty(); - if let Some(edition) = ALL_EDITIONS.iter().find(|e| name == e.feature_name()) { - if *edition <= crate_edition { + let edition = ALL_EDITIONS.iter().find(|e| name == e.feature_name()).copied(); + if let Some(edition) = edition { + if edition <= crate_edition { continue; } - for &(name, .., f_edition, set) in ACTIVE_FEATURES { - if let Some(f_edition) = f_edition { - if f_edition <= *edition { - // FIXME(Manishearth) there is currently no way to set - // lib features by edition - set(&mut features, DUMMY_SP); - edition_enabled_features.insert(name, *edition); - } - } + for feature in active_features_up_to(edition) { + // FIXME(Manishearth) there is currently no way to set + // lib features by edition + feature.set(&mut features, DUMMY_SP); + edition_enabled_features.insert(feature.name, edition); } } } @@ -867,6 +860,17 @@ pub fn get_features(span_handler: &Handler, krate_attrs: &[ast::Attribute], features } +fn active_features_up_to(edition: Edition) -> impl Iterator { + ACTIVE_FEATURES.iter() + .filter(move |feature| { + if let Some(feature_edition) = feature.edition { + feature_edition <= edition + } else { + false + } + }) +} + pub fn check_crate(krate: &ast::Crate, sess: &ParseSess, features: &Features,