Remove type-traversal trait aliases

compiler/rustc_trait_selection/src/traits/project.rs

@@ -30,8 +30,8 @@ use rustc_infer::infer::at::At;
 use rustc_infer::infer::resolve::OpportunisticRegionResolver;
 use rustc_infer::traits::ImplSourceBuiltinData;
 use rustc_middle::traits::select::OverflowError;
-use rustc_middle::ty::fold::{ir::TypeFolder, TypeFoldable, TypeSuperFoldable};
-use rustc_middle::ty::visit::{MaxUniverse, TypeVisitable};
+use rustc_middle::ty::fold::{TypeFoldable, TypeFolder, TypeSuperFoldable};
+use rustc_middle::ty::visit::{MaxUniverse, TypeVisitable, TypeVisitableExt};
 use rustc_middle::ty::DefIdTree;
 use rustc_middle::ty::{self, Term, ToPredicate, Ty, TyCtxt};
 use rustc_span::symbol::sym;
@@ -53,11 +53,11 @@ pub trait NormalizeExt<'tcx> {
     ///
     /// This normalization should be used when the type contains inference variables or the
     /// projection may be fallible.
-    fn normalize<T: TypeFoldable<'tcx>>(&self, t: T) -> InferOk<'tcx, T>;
+    fn normalize<T: TypeFoldable<TyCtxt<'tcx>>>(&self, t: T) -> InferOk<'tcx, T>;
 }
 
 impl<'tcx> NormalizeExt<'tcx> for At<'_, 'tcx> {
-    fn normalize<T: TypeFoldable<'tcx>>(&self, value: T) -> InferOk<'tcx, T> {
+    fn normalize<T: TypeFoldable<TyCtxt<'tcx>>>(&self, value: T) -> InferOk<'tcx, T> {
         let mut selcx = SelectionContext::new(self.infcx);
         let Normalized { value, obligations } =
             normalize_with_depth(&mut selcx, self.param_env, self.cause.clone(), 0, value);
@@ -312,7 +312,7 @@ pub(crate) fn normalize_with_depth<'a, 'b, 'tcx, T>(
     value: T,
 ) -> Normalized<'tcx, T>
 where
-    T: TypeFoldable<'tcx>,
+    T: TypeFoldable<TyCtxt<'tcx>>,
 {
     let mut obligations = Vec::new();
     let value = normalize_with_depth_to(selcx, param_env, cause, depth, value, &mut obligations);
@@ -329,7 +329,7 @@ pub(crate) fn normalize_with_depth_to<'a, 'b, 'tcx, T>(
     obligations: &mut Vec<PredicateObligation<'tcx>>,
 ) -> T
 where
-    T: TypeFoldable<'tcx>,
+    T: TypeFoldable<TyCtxt<'tcx>>,
 {
     debug!(obligations.len = obligations.len());
     let mut normalizer = AssocTypeNormalizer::new(selcx, param_env, cause, depth, obligations);
@@ -349,7 +349,7 @@ pub(crate) fn try_normalize_with_depth_to<'a, 'b, 'tcx, T>(
     obligations: &mut Vec<PredicateObligation<'tcx>>,
 ) -> T
 where
-    T: TypeFoldable<'tcx>,
+    T: TypeFoldable<TyCtxt<'tcx>>,
 {
     debug!(obligations.len = obligations.len());
     let mut normalizer = AssocTypeNormalizer::new_without_eager_inference_replacement(
@@ -365,7 +365,10 @@ where
     result
 }
 
-pub(crate) fn needs_normalization<'tcx, T: TypeVisitable<'tcx>>(value: &T, reveal: Reveal) -> bool {
+pub(crate) fn needs_normalization<'tcx, T: TypeVisitable<TyCtxt<'tcx>>>(
+    value: &T,
+    reveal: Reveal,
+) -> bool {
     match reveal {
         Reveal::UserFacing => value
             .has_type_flags(ty::TypeFlags::HAS_TY_PROJECTION | ty::TypeFlags::HAS_CT_PROJECTION),
@@ -427,7 +430,7 @@ impl<'a, 'b, 'tcx> AssocTypeNormalizer<'a, 'b, 'tcx> {
         }
     }
 
-    fn fold<T: TypeFoldable<'tcx>>(&mut self, value: T) -> T {
+    fn fold<T: TypeFoldable<TyCtxt<'tcx>>>(&mut self, value: T) -> T {
         let value = self.selcx.infcx.resolve_vars_if_possible(value);
         debug!(?value);
 
@@ -450,7 +453,7 @@ impl<'a, 'b, 'tcx> TypeFolder<TyCtxt<'tcx>> for AssocTypeNormalizer<'a, 'b, 'tcx
         self.selcx.tcx()
     }
 
-    fn fold_binder<T: TypeFoldable<'tcx>>(
+    fn fold_binder<T: TypeFoldable<TyCtxt<'tcx>>>(
         &mut self,
         t: ty::Binder<'tcx, T>,
     ) -> ty::Binder<'tcx, T> {
@@ -669,7 +672,12 @@ pub struct BoundVarReplacer<'me, 'tcx> {
 ///
 /// FIXME(@lcnr): We may even consider experimenting with eagerly replacing bound vars during
 /// normalization as well, at which point this function will be unnecessary and can be removed.
-pub fn with_replaced_escaping_bound_vars<'a, 'tcx, T: TypeFoldable<'tcx>, R: TypeFoldable<'tcx>>(
+pub fn with_replaced_escaping_bound_vars<
+    'a,
+    'tcx,
+    T: TypeFoldable<TyCtxt<'tcx>>,
+    R: TypeFoldable<TyCtxt<'tcx>>,
+>(
     infcx: &'a InferCtxt<'tcx>,
     universe_indices: &'a mut Vec<Option<ty::UniverseIndex>>,
     value: T,
@@ -695,7 +703,7 @@ pub fn with_replaced_escaping_bound_vars<'a, 'tcx, T: TypeFoldable<'tcx>, R: Typ
 impl<'me, 'tcx> BoundVarReplacer<'me, 'tcx> {
     /// Returns `Some` if we *were* able to replace bound vars. If there are any bound vars that
     /// use a binding level above `universe_indices.len()`, we fail.
-    pub fn replace_bound_vars<T: TypeFoldable<'tcx>>(
+    pub fn replace_bound_vars<T: TypeFoldable<TyCtxt<'tcx>>>(
         infcx: &'me InferCtxt<'tcx>,
         universe_indices: &'me mut Vec<Option<ty::UniverseIndex>>,
         value: T,
@@ -742,7 +750,7 @@ impl<'tcx> TypeFolder<TyCtxt<'tcx>> for BoundVarReplacer<'_, 'tcx> {
         self.infcx.tcx
     }
 
-    fn fold_binder<T: TypeFoldable<'tcx>>(
+    fn fold_binder<T: TypeFoldable<TyCtxt<'tcx>>>(
         &mut self,
         t: ty::Binder<'tcx, T>,
     ) -> ty::Binder<'tcx, T> {
@@ -823,7 +831,7 @@ pub struct PlaceholderReplacer<'me, 'tcx> {
 }
 
 impl<'me, 'tcx> PlaceholderReplacer<'me, 'tcx> {
-    pub fn replace_placeholders<T: TypeFoldable<'tcx>>(
+    pub fn replace_placeholders<T: TypeFoldable<TyCtxt<'tcx>>>(
         infcx: &'me InferCtxt<'tcx>,
         mapped_regions: BTreeMap<ty::PlaceholderRegion, ty::BoundRegion>,
         mapped_types: BTreeMap<ty::PlaceholderType, ty::BoundTy>,
@@ -848,7 +856,7 @@ impl<'tcx> TypeFolder<TyCtxt<'tcx>> for PlaceholderReplacer<'_, 'tcx> {
         self.infcx.tcx
     }
 
-    fn fold_binder<T: TypeFoldable<'tcx>>(
+    fn fold_binder<T: TypeFoldable<TyCtxt<'tcx>>>(
         &mut self,
         t: ty::Binder<'tcx, T>,
     ) -> ty::Binder<'tcx, T> {