Remove hir::Arm::attrs.

Author: cjgillot

compiler/rustc_ast_lowering/src/expr.rs

@@ -618,14 +618,8 @@ impl<'hir> LoweringContext<'_, 'hir> {
             }
         });
         let hir_id = self.next_id();
-        hir::Arm {
-            hir_id,
-            attrs: self.lower_attrs(hir_id, &arm.attrs),
-            pat,
-            guard,
-            body: self.lower_expr(&arm.body),
-            span: arm.span,
-        }
+        self.lower_attrs(hir_id, &arm.attrs);
+        hir::Arm { hir_id, pat, guard, body: self.lower_expr(&arm.body), span: arm.span }
     }
 
     /// Lower an `async` construct to a generator that is then wrapped so it implements `Future`.
@@ -2169,13 +2163,6 @@ impl<'hir> LoweringContext<'_, 'hir> {
     }
 
     fn arm(&mut self, pat: &'hir hir::Pat<'hir>, expr: &'hir hir::Expr<'hir>) -> hir::Arm<'hir> {
-        hir::Arm {
-            hir_id: self.next_id(),
-            attrs: &[],
-            pat,
-            guard: None,
-            span: expr.span,
-            body: expr,
-        }
+        hir::Arm { hir_id: self.next_id(), pat, guard: None, span: expr.span, body: expr }
     }
 }

compiler/rustc_hir/src/hir.rs

@@ -1188,7 +1188,6 @@ pub struct Arm<'hir> {
     #[stable_hasher(ignore)]
     pub hir_id: HirId,
     pub span: Span,
-    pub attrs: &'hir [Attribute],
     /// If this pattern and the optional guard matches, then `body` is evaluated.
     pub pat: &'hir Pat<'hir>,
     /// Optional guard clause.

compiler/rustc_hir_pretty/src/lib.rs

@@ -82,6 +82,7 @@ impl PpAnn for &dyn rustc_hir::intravisit::Map<'_> {
 pub struct State<'a> {
     pub s: pp::Printer,
     comments: Option<Comments<'a>>,
+    attrs: &'a hir::HirIdVec<&'a [ast::Attribute]>,
     ann: &'a (dyn PpAnn + 'a),
 }
 
@@ -163,7 +164,7 @@ pub fn print_crate<'a>(
     input: String,
     ann: &'a dyn PpAnn,
 ) -> String {
-    let mut s = State::new_from_input(sm, filename, input, ann);
+    let mut s = State::new_from_input(sm, filename, input, &krate.attrs, ann);
 
     // When printing the AST, we sometimes need to inject `#[no_std]` here.
     // Since you can't compile the HIR, it's not necessary.
@@ -178,17 +179,28 @@ impl<'a> State<'a> {
         sm: &'a SourceMap,
         filename: FileName,
         input: String,
+        attrs: &'a hir::HirIdVec<&[ast::Attribute]>,
         ann: &'a dyn PpAnn,
     ) -> State<'a> {
-        State { s: pp::mk_printer(), comments: Some(Comments::new(sm, filename, input)), ann }
+        State {
+            s: pp::mk_printer(),
+            comments: Some(Comments::new(sm, filename, input)),
+            attrs,
+            ann,
+        }
+    }
+
+    fn attrs(&self, id: hir::HirId) -> &'a [ast::Attribute] {
+        self.attrs.get(id).map_or(&[], |la| *la)
     }
 }
 
 pub fn to_string<F>(ann: &dyn PpAnn, f: F) -> String
 where
     F: FnOnce(&mut State<'_>),
 {
-    let mut printer = State { s: pp::mk_printer(), comments: None, ann };
+    let mut printer =
+        State { s: pp::mk_printer(), comments: None, attrs: &hir::HirIdVec::default(), ann };
     f(&mut printer);
     printer.s.eof()
 }
@@ -2027,13 +2039,13 @@ impl<'a> State<'a> {
     pub fn print_arm(&mut self, arm: &hir::Arm<'_>) {
         // I have no idea why this check is necessary, but here it
         // is :(
-        if arm.attrs.is_empty() {
+        if self.attrs(arm.hir_id).is_empty() {
             self.s.space();
         }
         self.cbox(INDENT_UNIT);
         self.ann.pre(self, AnnNode::Arm(arm));
         self.ibox(0);
-        self.print_outer_attributes(&arm.attrs);
+        self.print_outer_attributes(&self.attrs(arm.hir_id));
         self.print_pat(&arm.pat);
         self.s.space();
         if let Some(ref g) = arm.guard {

src/tools/clippy/clippy_lints/src/matches.rs

@@ -1207,11 +1207,11 @@ fn find_matches_sugg(cx: &LateContext<'_>, ex: &Expr<'_>, arms: &[Arm<'_>], expr
         if b0 != b1;
         let if_guard = &b0_arms[0].guard;
         if if_guard.is_none() || b0_arms.len() == 1;
-        if b0_arms[0].attrs.is_empty();
+        if cx.tcx.hir().attrs(b0_arms[0].hir_id).is_empty();
         if b0_arms[1..].iter()
             .all(|arm| {
                 find_bool_lit(&arm.body.kind, desugared).map_or(false, |b| b == b0) &&
-                arm.guard.is_none() && arm.attrs.is_empty()
+                arm.guard.is_none() && cx.tcx.hir().attrs(arm.hir_id).is_empty()
             });
         then {
             // The suggestion may be incorrect, because some arms can have `cfg` attributes

src/tools/clippy/clippy_lints/src/utils/inspector.rs

@@ -96,7 +96,7 @@ impl<'tcx> LateLintPass<'tcx> for DeepCodeInspector {
     }
 
     fn check_arm(&mut self, cx: &LateContext<'tcx>, arm: &'tcx hir::Arm<'_>) {
-        if !has_attr(cx.sess(), &arm.attrs) {
+        if !has_attr(cx.sess(), cx.tcx.hir().attrs(arm.hir_id)) {
             return;
         }
         print_pat(cx, &arm.pat, 1);