Make folding traits generic over the Interner

compiler/rustc_infer/src/infer/canonical/canonicalizer.rs

@@ -326,7 +326,7 @@ struct Canonicalizer<'cx, 'tcx> {
     binder_index: ty::DebruijnIndex,
 }
 
-impl<'cx, 'tcx> TypeFolder<'tcx> for Canonicalizer<'cx, 'tcx> {
+impl<'cx, 'tcx> TypeFolder<TyCtxt<'tcx>> for Canonicalizer<'cx, 'tcx> {
     fn tcx<'b>(&'b self) -> TyCtxt<'tcx> {
         self.tcx
     }

compiler/rustc_infer/src/infer/combine.rs

@@ -844,7 +844,7 @@ struct ConstInferUnifier<'cx, 'tcx> {
     target_vid: ty::ConstVid<'tcx>,
 }
 
-impl<'tcx> FallibleTypeFolder<'tcx> for ConstInferUnifier<'_, 'tcx> {
+impl<'tcx> FallibleTypeFolder<TyCtxt<'tcx>> for ConstInferUnifier<'_, 'tcx> {
     type Error = TypeError<'tcx>;
 
     fn tcx<'a>(&'a self) -> TyCtxt<'tcx> {

compiler/rustc_infer/src/infer/freshen.rs

@@ -105,7 +105,7 @@ impl<'a, 'tcx> TypeFreshener<'a, 'tcx> {
     }
 }
 
-impl<'a, 'tcx> TypeFolder<'tcx> for TypeFreshener<'a, 'tcx> {
+impl<'a, 'tcx> TypeFolder<TyCtxt<'tcx>> for TypeFreshener<'a, 'tcx> {
     fn tcx<'b>(&'b self) -> TyCtxt<'tcx> {
         self.infcx.tcx
     }

compiler/rustc_infer/src/infer/fudge.rs

@@ -175,7 +175,7 @@ pub struct InferenceFudger<'a, 'tcx> {
     const_vars: (Range<ConstVid<'tcx>>, Vec<ConstVariableOrigin>),
 }
 
-impl<'a, 'tcx> TypeFolder<'tcx> for InferenceFudger<'a, 'tcx> {
+impl<'a, 'tcx> TypeFolder<TyCtxt<'tcx>> for InferenceFudger<'a, 'tcx> {
     fn tcx<'b>(&'b self) -> TyCtxt<'tcx> {
         self.infcx.tcx
     }

compiler/rustc_infer/src/infer/mod.rs

@@ -1852,7 +1852,7 @@ struct InferenceLiteralEraser<'tcx> {
     tcx: TyCtxt<'tcx>,
 }
 
-impl<'tcx> TypeFolder<'tcx> for InferenceLiteralEraser<'tcx> {
+impl<'tcx> TypeFolder<TyCtxt<'tcx>> for InferenceLiteralEraser<'tcx> {
     fn tcx(&self) -> TyCtxt<'tcx> {
         self.tcx
     }
@@ -1870,7 +1870,7 @@ struct ShallowResolver<'a, 'tcx> {
     infcx: &'a InferCtxt<'tcx>,
 }
 
-impl<'a, 'tcx> TypeFolder<'tcx> for ShallowResolver<'a, 'tcx> {
+impl<'a, 'tcx> TypeFolder<TyCtxt<'tcx>> for ShallowResolver<'a, 'tcx> {
     fn tcx<'b>(&'b self) -> TyCtxt<'tcx> {
         self.infcx.tcx
     }
@@ -2064,7 +2064,7 @@ fn replace_param_and_infer_substs_with_placeholder<'tcx>(
         idx: u32,
     }
 
-    impl<'tcx> TypeFolder<'tcx> for ReplaceParamAndInferWithPlaceholder<'tcx> {
+    impl<'tcx> TypeFolder<TyCtxt<'tcx>> for ReplaceParamAndInferWithPlaceholder<'tcx> {
         fn tcx(&self) -> TyCtxt<'tcx> {
             self.tcx
         }

compiler/rustc_infer/src/infer/resolve.rs

@@ -31,7 +31,7 @@ impl<'a, 'tcx> OpportunisticVarResolver<'a, 'tcx> {
     }
 }
 
-impl<'a, 'tcx> TypeFolder<'tcx> for OpportunisticVarResolver<'a, 'tcx> {
+impl<'a, 'tcx> TypeFolder<TyCtxt<'tcx>> for OpportunisticVarResolver<'a, 'tcx> {
     fn tcx<'b>(&'b self) -> TyCtxt<'tcx> {
         TypeFolder::tcx(&self.shallow_resolver)
     }
@@ -73,7 +73,7 @@ impl<'a, 'tcx> OpportunisticRegionResolver<'a, 'tcx> {
     }
 }
 
-impl<'a, 'tcx> TypeFolder<'tcx> for OpportunisticRegionResolver<'a, 'tcx> {
+impl<'a, 'tcx> TypeFolder<TyCtxt<'tcx>> for OpportunisticRegionResolver<'a, 'tcx> {
     fn tcx<'b>(&'b self) -> TyCtxt<'tcx> {
         self.infcx.tcx
     }
@@ -211,7 +211,7 @@ struct FullTypeResolver<'a, 'tcx> {
     infcx: &'a InferCtxt<'tcx>,
 }
 
-impl<'a, 'tcx> FallibleTypeFolder<'tcx> for FullTypeResolver<'a, 'tcx> {
+impl<'a, 'tcx> FallibleTypeFolder<TyCtxt<'tcx>> for FullTypeResolver<'a, 'tcx> {
     type Error = FixupError<'tcx>;
 
     fn tcx<'b>(&'b self) -> TyCtxt<'tcx> {

compiler/rustc_infer/src/traits/structural_impls.rs

@@ -61,7 +61,7 @@ impl<'tcx> fmt::Debug for traits::MismatchedProjectionTypes<'tcx> {
 ///////////////////////////////////////////////////////////////////////////
 // TypeFoldable implementations.
 
-impl<'tcx, O: TypeFoldable<'tcx>> ir::TypeFoldable<'tcx> for traits::Obligation<'tcx, O> {
+impl<'tcx, O: TypeFoldable<'tcx>> ir::TypeFoldable<TyCtxt<'tcx>> for traits::Obligation<'tcx, O> {
     fn try_fold_with<F: FallibleTypeFolder<'tcx>>(self, folder: &mut F) -> Result<Self, F::Error> {
         Ok(traits::Obligation {
             cause: self.cause,