Make provided_trait_methods use impl Iterator

Author: jonas-schievink

src/librustc/ty/mod.rs

@@ -2705,11 +2705,10 @@ impl<'tcx> TyCtxt<'tcx> {
             .for_each(|&body_id| f(self.hir().body_owner_def_id(body_id)));
     }
 
-    pub fn provided_trait_methods(self, id: DefId) -> Vec<&'tcx AssocItem> {
+    pub fn provided_trait_methods(self, id: DefId) -> impl Iterator<Item = &'tcx AssocItem> {
         self.associated_items(id)
             .iter()
             .filter(|item| item.kind == AssocKind::Method && item.defaultness.has_value())
-            .collect()
     }
 
     pub fn trait_relevant_for_never(self, did: DefId) -> bool {

src/librustc_passes/reachable.rs

@@ -362,12 +362,12 @@ impl<'a, 'tcx> ItemLikeVisitor<'tcx> for CollectPrivateImplItemsVisitor<'a, 'tcx
                     return;
                 }
 
-                let provided_trait_methods = self.tcx.provided_trait_methods(trait_def_id);
-                self.worklist.reserve(provided_trait_methods.len());
-                for default_method in provided_trait_methods {
-                    let hir_id = self.tcx.hir().as_local_hir_id(default_method.def_id).unwrap();
-                    self.worklist.push(hir_id);
-                }
+                // FIXME(#53488) remove `let`
+                let tcx = self.tcx;
+                self.worklist.extend(
+                    tcx.provided_trait_methods(trait_def_id)
+                        .map(|assoc| tcx.hir().as_local_hir_id(assoc.def_id).unwrap()),
+                );
             }
         }
     }

src/librustdoc/clean/blanket_impl.rs

@@ -87,7 +87,6 @@ impl<'a, 'tcx> BlanketImplFinder<'a, 'tcx> {
                     .cx
                     .tcx
                     .provided_trait_methods(trait_def_id)
-                    .into_iter()
                     .map(|meth| meth.ident.to_string())
                     .collect();
 

src/librustdoc/clean/inline.rs

@@ -402,9 +402,7 @@ pub fn build_impl(
 
     let provided = trait_
         .def_id()
-        .map(|did| {
-            tcx.provided_trait_methods(did).into_iter().map(|meth| meth.ident.to_string()).collect()
-        })
+        .map(|did| tcx.provided_trait_methods(did).map(|meth| meth.ident.to_string()).collect())
         .unwrap_or_default();
 
     debug!("build_impl: impl {:?} for {:?}", trait_.def_id(), for_.def_id());

src/librustdoc/clean/mod.rs

@@ -2108,11 +2108,7 @@ impl Clean<Vec<Item>> for doctree::Impl<'_> {
         let provided: FxHashSet<String> = trait_
             .def_id()
             .map(|did| {
-                cx.tcx
-                    .provided_trait_methods(did)
-                    .into_iter()
-                    .map(|meth| meth.ident.to_string())
-                    .collect()
+                cx.tcx.provided_trait_methods(did).map(|meth| meth.ident.to_string()).collect()
             })
             .unwrap_or_default();