Rollup merge of #152550 - Ozzy1423:rustc-attrs, r=JonathanBrouwer

Port #[prelude_import] to the attribute parser

Tracking issue: #131229

r? @JonathanBrouwer

Didn't change any use-sites of it in the compiler

Author: Zalathar

compiler/rustc_attr_parsing/src/attributes/rustc_internal.rs

@@ -1211,3 +1211,12 @@ impl<S: Stage> SingleAttributeParser<S> for RustcReservationImplParser {
         Some(AttributeKind::RustcReservationImpl(cx.attr_span, value_str))
     }
 }
+
+pub(crate) struct PreludeImportParser;
+
+impl<S: Stage> NoArgsAttributeParser<S> for PreludeImportParser {
+    const PATH: &[Symbol] = &[sym::prelude_import];
+    const ON_DUPLICATE: OnDuplicate<S> = OnDuplicate::Warn;
+    const ALLOWED_TARGETS: AllowedTargets = AllowedTargets::AllowList(&[Allow(Target::Use)]);
+    const CREATE: fn(Span) -> AttributeKind = |_| AttributeKind::PreludeImport;
+}

compiler/rustc_attr_parsing/src/context.rs

@@ -258,6 +258,7 @@ attribute_parsers!(
         Single<WithoutArgs<PassByValueParser>>,
         Single<WithoutArgs<PinV2Parser>>,
         Single<WithoutArgs<PointeeParser>>,
+        Single<WithoutArgs<PreludeImportParser>>,
         Single<WithoutArgs<ProcMacroAttributeParser>>,
         Single<WithoutArgs<ProcMacroParser>>,
         Single<WithoutArgs<ProfilerRuntimeParser>>,

compiler/rustc_hir/src/attrs/data_structures.rs

@@ -1053,6 +1053,9 @@ pub enum AttributeKind {
     /// Represents `#[pointee]`
     Pointee(Span),
 
+    /// Represents `#[prelude_import]`
+    PreludeImport,
+
     /// Represents `#[proc_macro]`
     ProcMacro(Span),
 

compiler/rustc_hir/src/attrs/encode_cross_crate.rs

@@ -82,6 +82,7 @@ impl AttributeKind {
             PatternComplexityLimit { .. } => No,
             PinV2(..) => Yes,
             Pointee(..) => No,
+            PreludeImport => No,
             ProcMacro(..) => No,
             ProcMacroAttribute(..) => No,
             ProcMacroDerive { .. } => No,

compiler/rustc_passes/src/check_attr.rs

@@ -282,6 +282,7 @@ impl<'tcx> CheckAttrVisitor<'tcx> {
                     | AttributeKind::PatternComplexityLimit { .. }
                     | AttributeKind::PinV2(..)
                     | AttributeKind::Pointee(..)
+                    | AttributeKind::PreludeImport
                     | AttributeKind::ProfilerRuntime
                     | AttributeKind::RecursionLimit { .. }
                     | AttributeKind::ReexportTestHarnessMain(..)
@@ -394,7 +395,6 @@ impl<'tcx> CheckAttrVisitor<'tcx> {
                             // need to be fixed
                             | sym::deprecated_safe // FIXME(deprecated_safe)
                             // internal
-                            | sym::prelude_import
                             | sym::panic_handler
                             | sym::lang
                             | sym::default_lib_allocator

tests/pretty/delegation-inherit-attributes.pp

@@ -7,7 +7,7 @@
 #![allow(incomplete_features)]
 #![feature(fn_delegation)]
 extern crate std;
-#[prelude_import]
+#[attr = PreludeImport]
 use std::prelude::rust_2021::*;
 
 extern crate to_reuse_functions;

tests/pretty/delegation-inline-attribute.pp

@@ -5,7 +5,7 @@
 #![allow(incomplete_features)]
 #![feature(fn_delegation)]
 extern crate std;
-#[prelude_import]
+#[attr = PreludeImport]
 use ::std::prelude::rust_2015::*;
 
 mod to_reuse {

tests/pretty/hir-delegation.pp

@@ -5,7 +5,7 @@
 #![allow(incomplete_features)]
 #![feature(fn_delegation)]
 extern crate std;
-#[prelude_import]
+#[attr = PreludeImport]
 use ::std::prelude::rust_2015::*;
 
 fn b<C>(e: C) { }

tests/pretty/hir-fn-params.pp

@@ -1,5 +1,5 @@
 extern crate std;
-#[prelude_import]
+#[attr = PreludeImport]
 use ::std::prelude::rust_2015::*;
 //@ pretty-compare-only
 //@ pretty-mode:hir

tests/pretty/hir-fn-variadic.pp

@@ -4,7 +4,7 @@
 
 #![feature(c_variadic)]
 extern crate std;
-#[prelude_import]
+#[attr = PreludeImport]
 use ::std::prelude::rust_2015::*;
 
 extern "C" {