Auto merge of #112938 - compiler-errors:clause-3, r=oli-obk

Migrate `TyCtxt::predicates_of` and `ParamEnv::caller_bounds` to `Clause`

The last big change in the series.

I will follow-up with additional filed issues once this PR lands:
- [ ] Investigate making `TypeFoldable<TyCtxt<'tcx>> for ty::Clause<'tcx>` implementation less weird: https://github.com/rust-lang/rust/blob/2efe09170530fa18e42ff05b8d9dd23f00b5c430/compiler/rustc_middle/src/ty/structural_impls.rs#L672
- [ ] Clean up the elaborator since it should only be emitting child clauses, not predicates
- [ ] Rename identifiers like `pred` and `predicates` to `clause` if they're actually clauses around the codebase
- [ ] Validate that all of the `ToPredicate` impls are acutally still needed, or prune them if they're not

r? `@ghost` until the other branch lands

2 files changed, 7 insertions, 7 deletions

diff --git a/compiler/rustc_borrowck/src/diagnostics/conflict_errors.rs b/compiler/rustc_borrowck/src/diagnostics/conflict_errors.rs
index 5c365e98f0b..39b05829888 100644
--- a/compiler/rustc_borrowck/src/diagnostics/conflict_errors.rs
+++ b/compiler/rustc_borrowck/src/diagnostics/conflict_errors.rs
@@ -678,8 +678,8 @@ impl<'cx, 'tcx> MirBorrowckCtxt<'cx, 'tcx> {
         let tcx = self.infcx.tcx;
 
         // Find out if the predicates show that the type is a Fn or FnMut
-        let find_fn_kind_from_did = |(pred, _): (ty::Predicate<'tcx>, _)| {
-            if let ty::PredicateKind::Clause(ty::ClauseKind::Trait(pred)) = pred.kind().skip_binder()
+        let find_fn_kind_from_did = |(pred, _): (ty::Clause<'tcx>, _)| {
+            if let ty::ClauseKind::Trait(pred) = pred.kind().skip_binder()
                 && pred.self_ty() == ty
             {
                 if Some(pred.def_id()) == tcx.lang_items().fn_trait() {
@@ -705,7 +705,7 @@ impl<'cx, 'tcx> MirBorrowckCtxt<'cx, 'tcx> {
             ty::Alias(ty::Opaque, ty::AliasTy { def_id, substs, .. }) => tcx
                 .explicit_item_bounds(def_id)
                 .subst_iter_copied(tcx, substs)
-                .find_map(|(clause, span)| find_fn_kind_from_did((clause.as_predicate(), span))),
+                .find_map(|(clause, span)| find_fn_kind_from_did((clause, span))),
             ty::Closure(_, substs) => match substs.as_closure().kind() {
                 ty::ClosureKind::Fn => Some(hir::Mutability::Not),
                 ty::ClosureKind::FnMut => Some(hir::Mutability::Mut),
diff --git a/compiler/rustc_borrowck/src/diagnostics/region_name.rs b/compiler/rustc_borrowck/src/diagnostics/region_name.rs
index 55c9864af8c..074f37bed13 100644
--- a/compiler/rustc_borrowck/src/diagnostics/region_name.rs
+++ b/compiler/rustc_borrowck/src/diagnostics/region_name.rs
@@ -928,7 +928,7 @@ impl<'tcx> MirBorrowckCtxt<'_, 'tcx> {
 
     fn any_param_predicate_mentions(
         &self,
-        predicates: &[ty::Predicate<'tcx>],
+        clauses: &[ty::Clause<'tcx>],
         ty: Ty<'tcx>,
         region: ty::EarlyBoundRegion,
     ) -> bool {
@@ -937,10 +937,10 @@ impl<'tcx> MirBorrowckCtxt<'_, 'tcx> {
             if let ty::GenericArgKind::Type(ty) = arg.unpack()
                 && let ty::Param(_) = ty.kind()
             {
-                predicates.iter().any(|pred| {
+                clauses.iter().any(|pred| {
                     match pred.kind().skip_binder() {
-                        ty::PredicateKind::Clause(ty::ClauseKind::Trait(data)) if data.self_ty() == ty => {}
-                        ty::PredicateKind::Clause(ty::ClauseKind::Projection(data)) if data.projection_ty.self_ty() == ty => {}
+                        ty::ClauseKind::Trait(data) if data.self_ty() == ty => {}
+                        ty::ClauseKind::Projection(data) if data.projection_ty.self_ty() == ty => {}
                         _ => return false,
                     }
                     tcx.any_free_region_meets(pred, |r| {