Auto merge of #97697 - WaffleLapkin:no_ref_vec, r=WaffleLapkin

Replace `&Vec<_>`s with `&[_]`s

It's generally preferable to use `&[_]` since it's one less indirection and it can be created from types other that `Vec`.

I've left `&Vec` in some locals where it doesn't really matter, in cases where `TypeFoldable` is expected (`TypeFoldable: Clone` so slice can't implement it) and in cases where it's `&TypeAliasThatIsActiallyVec`. Nothing important, really, I was just a little annoyed by `visit_generic_param_vec` :D

r? `@compiler-errors`

2 files changed, 7 insertions, 5 deletions

diff --git a/compiler/rustc_trait_selection/src/traits/error_reporting/suggestions.rs b/compiler/rustc_trait_selection/src/traits/error_reporting/suggestions.rs
index d0f20022bfb..fd0732f51d5 100644
--- a/compiler/rustc_trait_selection/src/traits/error_reporting/suggestions.rs
+++ b/compiler/rustc_trait_selection/src/traits/error_reporting/suggestions.rs
@@ -146,11 +146,13 @@ impl<'tcx, 'a> GeneratorData<'tcx, 'a> {
     /// that are live across the yield of this generator
     fn get_generator_interior_types(
         &self,
-    ) -> ty::Binder<'tcx, &Vec<GeneratorInteriorTypeCause<'tcx>>> {
+    ) -> ty::Binder<'tcx, &[GeneratorInteriorTypeCause<'tcx>]> {
         match self {
-            GeneratorData::Local(typeck_result) => typeck_result.generator_interior_types.as_ref(),
+            GeneratorData::Local(typeck_result) => {
+                typeck_result.generator_interior_types.as_deref()
+            }
             GeneratorData::Foreign(generator_diagnostic_data) => {
-                generator_diagnostic_data.generator_interior_types.as_ref()
+                generator_diagnostic_data.generator_interior_types.as_deref()
             }
         }
     }
diff --git a/compiler/rustc_trait_selection/src/traits/project.rs b/compiler/rustc_trait_selection/src/traits/project.rs
index 641b915f373..17e0fae9853 100644
--- a/compiler/rustc_trait_selection/src/traits/project.rs
+++ b/compiler/rustc_trait_selection/src/traits/project.rs
@@ -773,7 +773,7 @@ pub struct PlaceholderReplacer<'me, 'tcx> {
     mapped_regions: BTreeMap<ty::PlaceholderRegion, ty::BoundRegion>,
     mapped_types: BTreeMap<ty::PlaceholderType, ty::BoundTy>,
     mapped_consts: BTreeMap<ty::PlaceholderConst<'tcx>, ty::BoundVar>,
-    universe_indices: &'me Vec<Option<ty::UniverseIndex>>,
+    universe_indices: &'me [Option<ty::UniverseIndex>],
     current_index: ty::DebruijnIndex,
 }
 
@@ -783,7 +783,7 @@ impl<'me, 'tcx> PlaceholderReplacer<'me, 'tcx> {
         mapped_regions: BTreeMap<ty::PlaceholderRegion, ty::BoundRegion>,
         mapped_types: BTreeMap<ty::PlaceholderType, ty::BoundTy>,
         mapped_consts: BTreeMap<ty::PlaceholderConst<'tcx>, ty::BoundVar>,
-        universe_indices: &'me Vec<Option<ty::UniverseIndex>>,
+        universe_indices: &'me [Option<ty::UniverseIndex>],
         value: T,
     ) -> T {
         let mut replacer = PlaceholderReplacer {