Rollup merge of #128110 - veera-sivarajan:bugfix-80173, r=cjgillot

Suggest Replacing Comma with Semicolon in Incorrect Repeat Expressions

Fixes #80173

This PR detects typos in repeat expressions like `["_", 10]` and `vec![String::new(), 10]` and suggests replacing comma with semicolon.

Also, improves code in other place by adding doc comments and making use of a helper function to check if a type implements `Clone`.

References:
1. For `vec![T; N]`: https://doc.rust-lang.org/std/macro.vec.html
2. For `[T; N]`: https://doc.rust-lang.org/std/primitive.array.html

1 files changed, 6 insertions, 0 deletions

diff --git a/compiler/rustc_trait_selection/src/infer.rs b/compiler/rustc_trait_selection/src/infer.rs
index ee708564a80..f373706b296 100644
--- a/compiler/rustc_trait_selection/src/infer.rs
+++ b/compiler/rustc_trait_selection/src/infer.rs
@@ -47,6 +47,12 @@ impl<'tcx> InferCtxt<'tcx> {
         traits::type_known_to_meet_bound_modulo_regions(self, param_env, ty, copy_def_id)
     }
 
+    fn type_is_clone_modulo_regions(&self, param_env: ty::ParamEnv<'tcx>, ty: Ty<'tcx>) -> bool {
+        let ty = self.resolve_vars_if_possible(ty);
+        let clone_def_id = self.tcx.require_lang_item(LangItem::Clone, None);
+        traits::type_known_to_meet_bound_modulo_regions(self, param_env, ty, clone_def_id)
+    }
+
     fn type_is_sized_modulo_regions(&self, param_env: ty::ParamEnv<'tcx>, ty: Ty<'tcx>) -> bool {
         let lang_item = self.tcx.require_lang_item(LangItem::Sized, None);
         traits::type_known_to_meet_bound_modulo_regions(self, param_env, ty, lang_item)