Auto merge of #131808 - jdonszelmann:hir-attributes, r=oli-obk,petrochenkov

Hir attributes

This PR needs some explanation, it's somewhat large.

- This is step one as described in https://github.com/rust-lang/compiler-team/issues/796. I've added a new `hir::Attribute` which is a lowered version of `ast::Attribute`. Right now, this has few concrete effects, however every place that after this PR parses a `hir::Attribute` should later get a pre-parsed attribute as described in https://github.com/rust-lang/compiler-team/issues/796 and transitively https://github.com/rust-lang/rust/issues/131229.
- an extension trait `AttributeExt` is added, which is implemented for both `ast::Attribute` and `hir::Atribute`. This makes `hir::Attributes` mostly compatible with code that used to parse `ast::Attribute`. All its methods are also added as inherent methods to avoid having to import the trait everywhere in the compiler.
  - Incremental can not not hash `ast::Attribute` at all.

3 files changed, 8 insertions, 13 deletions

diff --git a/compiler/rustc_parse/src/parser/attr.rs b/compiler/rustc_parse/src/parser/attr.rs
index b6fa2099588..8cf37671185 100644
--- a/compiler/rustc_parse/src/parser/attr.rs
+++ b/compiler/rustc_parse/src/parser/attr.rs
@@ -1,6 +1,5 @@
-use rustc_ast as ast;
-use rustc_ast::attr;
 use rustc_ast::token::{self, Delimiter};
+use rustc_ast::{self as ast, Attribute, attr};
 use rustc_errors::codes::*;
 use rustc_errors::{Diag, PResult};
 use rustc_span::symbol::kw;
@@ -48,7 +47,7 @@ impl<'a> Parser<'a> {
         let start_pos = self.num_bump_calls;
         loop {
             let attr = if self.check(&token::Pound) {
-                let prev_outer_attr_sp = outer_attrs.last().map(|attr| attr.span);
+                let prev_outer_attr_sp = outer_attrs.last().map(|attr: &Attribute| attr.span);
 
                 let inner_error_reason = if just_parsed_doc_comment {
                     Some(InnerAttrForbiddenReason::AfterOuterDocComment {
diff --git a/compiler/rustc_parse/src/parser/mod.rs b/compiler/rustc_parse/src/parser/mod.rs
index 37556c064d8..976ffe608a2 100644
--- a/compiler/rustc_parse/src/parser/mod.rs
+++ b/compiler/rustc_parse/src/parser/mod.rs
@@ -29,9 +29,9 @@ use rustc_ast::tokenstream::{
 };
 use rustc_ast::util::case::Case;
 use rustc_ast::{
-    self as ast, AnonConst, AttrArgs, AttrArgsEq, AttrId, ByRef, Const, CoroutineKind,
-    DUMMY_NODE_ID, DelimArgs, Expr, ExprKind, Extern, HasAttrs, HasTokens, Mutability, Recovered,
-    Safety, StrLit, Visibility, VisibilityKind,
+    self as ast, AnonConst, AttrArgs, AttrId, ByRef, Const, CoroutineKind, DUMMY_NODE_ID,
+    DelimArgs, Expr, ExprKind, Extern, HasAttrs, HasTokens, Mutability, Recovered, Safety, StrLit,
+    Visibility, VisibilityKind,
 };
 use rustc_ast_pretty::pprust;
 use rustc_data_structures::fx::FxHashMap;
@@ -1376,7 +1376,7 @@ impl<'a> Parser<'a> {
             AttrArgs::Delimited(args)
         } else if self.eat(&token::Eq) {
             let eq_span = self.prev_token.span;
-            AttrArgs::Eq { eq_span, value: AttrArgsEq::Ast(self.parse_expr_force_collect()?) }
+            AttrArgs::Eq { eq_span, expr: self.parse_expr_force_collect()? }
         } else {
             AttrArgs::Empty
         })
diff --git a/compiler/rustc_parse/src/validate_attr.rs b/compiler/rustc_parse/src/validate_attr.rs
index aab3f10bc66..8b6b37c0f8f 100644
--- a/compiler/rustc_parse/src/validate_attr.rs
+++ b/compiler/rustc_parse/src/validate_attr.rs
@@ -3,8 +3,7 @@
 use rustc_ast::token::Delimiter;
 use rustc_ast::tokenstream::DelimSpan;
 use rustc_ast::{
-    self as ast, AttrArgs, AttrArgsEq, Attribute, DelimArgs, MetaItem, MetaItemInner, MetaItemKind,
-    Safety,
+    self as ast, AttrArgs, Attribute, DelimArgs, MetaItem, MetaItemInner, MetaItemKind, Safety,
 };
 use rustc_errors::{Applicability, FatalError, PResult};
 use rustc_feature::{AttributeSafety, AttributeTemplate, BUILTIN_ATTRIBUTE_MAP, BuiltinAttribute};
@@ -70,7 +69,7 @@ pub fn parse_meta<'a>(psess: &'a ParseSess, attr: &Attribute) -> PResult<'a, Met
                     parse_in(psess, tokens.clone(), "meta list", |p| p.parse_meta_seq_top())?;
                 MetaItemKind::List(nmis)
             }
-            AttrArgs::Eq { value: AttrArgsEq::Ast(expr), .. } => {
+            AttrArgs::Eq { expr, .. } => {
                 if let ast::ExprKind::Lit(token_lit) = expr.kind {
                     let res = ast::MetaItemLit::from_token_lit(token_lit, expr.span);
                     let res = match res {
@@ -116,9 +115,6 @@ pub fn parse_meta<'a>(psess: &'a ParseSess, attr: &Attribute) -> PResult<'a, Met
                     return Err(err);
                 }
             }
-            AttrArgs::Eq { value: AttrArgsEq::Hir(lit), .. } => {
-                MetaItemKind::NameValue(lit.clone())
-            }
         },
     })
 }