Rollup merge of #97023 - cjgillot:uniform-anon, r=estebank

Diagnose anonymous lifetimes errors more uniformly between async and regular fns

Async fns and regular fns are desugared differently.  For the former, we create a generic parameter at HIR level.  For the latter, we just create an anonymous region for typeck.

I plan to migrate regular fns to the async fn desugaring.

Before that, this PR attempts to merge the diagnostics for both cases.

r? ```@estebank```

1 files changed, 6 insertions, 4 deletions

diff --git a/compiler/rustc_borrowck/src/diagnostics/region_name.rs b/compiler/rustc_borrowck/src/diagnostics/region_name.rs
index 4d2a16aa609..cb4b154d271 100644
--- a/compiler/rustc_borrowck/src/diagnostics/region_name.rs
+++ b/compiler/rustc_borrowck/src/diagnostics/region_name.rs
@@ -567,15 +567,17 @@ impl<'tcx> MirBorrowckCtxt<'_, 'tcx> {
         let lifetime =
             self.try_match_adt_and_generic_args(substs, needle_fr, args, search_stack)?;
         match lifetime.name {
-            hir::LifetimeName::Param(_)
+            hir::LifetimeName::Param(hir::ParamName::Plain(_) | hir::ParamName::Error)
             | hir::LifetimeName::Error
-            | hir::LifetimeName::Static
-            | hir::LifetimeName::Underscore => {
+            | hir::LifetimeName::Static => {
                 let lifetime_span = lifetime.span;
                 Some(RegionNameHighlight::MatchedAdtAndSegment(lifetime_span))
             }
 
-            hir::LifetimeName::ImplicitObjectLifetimeDefault | hir::LifetimeName::Implicit => {
+            hir::LifetimeName::Param(hir::ParamName::Fresh(_))
+            | hir::LifetimeName::ImplicitObjectLifetimeDefault
+            | hir::LifetimeName::Implicit
+            | hir::LifetimeName::Underscore => {
                 // In this case, the user left off the lifetime; so
                 // they wrote something like:
                 //