Auto merge of #101241 - camsteffen:refactor-binding-annotations, r=cjgillot

`BindingAnnotation` refactor

* `ast::BindingMode` is deleted and replaced with `hir::BindingAnnotation` (which is moved to `ast`)
* `BindingAnnotation` is changed from an enum to a tuple struct e.g. `BindingAnnotation(ByRef::No, Mutability::Mut)`
* Associated constants added for convenience `BindingAnnotation::{NONE, REF, MUT, REF_MUT}`

One goal is to make it more clear that `BindingAnnotation` merely represents syntax `ref mut` and not the actual binding mode. This was especially confusing since we had `ast::BindingMode`->`hir::BindingAnnotation`->`thir::BindingMode`.

I wish there were more symmetry between `ByRef` and `Mutability` (variant) naming (maybe `Mutable::Yes`?), and I also don't love how long the name `BindingAnnotation` is, but this seems like the best compromise. Ideas welcome.

1 files changed, 1 insertions, 1 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 02adae5bde1..b012073f771 100644
--- a/compiler/rustc_trait_selection/src/traits/error_reporting/suggestions.rs
+++ b/compiler/rustc_trait_selection/src/traits/error_reporting/suggestions.rs
@@ -774,7 +774,7 @@ impl<'a, 'tcx> InferCtxtExt<'tcx> for InferCtxt<'a, 'tcx> {
             // Get the local name of this closure. This can be inaccurate because
             // of the possibility of reassignment, but this should be good enough.
             match &kind {
-                hir::PatKind::Binding(hir::BindingAnnotation::Unannotated, _, ident, None) => {
+                hir::PatKind::Binding(hir::BindingAnnotation::NONE, _, ident, None) => {
                     Some(ident.name)
                 }
                 _ => {