Squash fold into ty

Author: compiler-errors

compiler/rustc_borrowck/src/diagnostics/region_errors.rs

@@ -14,9 +14,8 @@ use rustc_infer::infer::{NllRegionVariableOrigin, RelateParamBound};
 use rustc_middle::bug;
 use rustc_middle::hir::place::PlaceBase;
 use rustc_middle::mir::{AnnotationSource, ConstraintCategory, ReturnConstraint};
-use rustc_middle::ty::fold::fold_regions;
 use rustc_middle::ty::{
-    self, GenericArgs, Region, RegionVid, Ty, TyCtxt, TypeFoldable, TypeVisitor,
+    self, GenericArgs, Region, RegionVid, Ty, TyCtxt, TypeFoldable, TypeVisitor, fold_regions,
 };
 use rustc_span::{Ident, Span, kw};
 use rustc_trait_selection::error_reporting::InferCtxtErrorExt;

compiler/rustc_borrowck/src/lib.rs

@@ -35,8 +35,7 @@ use rustc_infer::infer::{
 };
 use rustc_middle::mir::*;
 use rustc_middle::query::Providers;
-use rustc_middle::ty::fold::fold_regions;
-use rustc_middle::ty::{self, ParamEnv, RegionVid, TyCtxt, TypingMode};
+use rustc_middle::ty::{self, ParamEnv, RegionVid, TyCtxt, TypingMode, fold_regions};
 use rustc_middle::{bug, span_bug};
 use rustc_mir_dataflow::impls::{
     EverInitializedPlaces, MaybeInitializedPlaces, MaybeUninitializedPlaces,

compiler/rustc_borrowck/src/region_infer/mod.rs

@@ -18,8 +18,7 @@ use rustc_middle::mir::{
     ReturnConstraint, TerminatorKind,
 };
 use rustc_middle::traits::{ObligationCause, ObligationCauseCode};
-use rustc_middle::ty::fold::fold_regions;
-use rustc_middle::ty::{self, RegionVid, Ty, TyCtxt, TypeFoldable, UniverseIndex};
+use rustc_middle::ty::{self, RegionVid, Ty, TyCtxt, TypeFoldable, UniverseIndex, fold_regions};
 use rustc_mir_dataflow::points::DenseLocationMap;
 use rustc_span::hygiene::DesugaringKind;
 use rustc_span::{DUMMY_SP, Span};

compiler/rustc_borrowck/src/region_infer/opaque_types.rs

@@ -5,11 +5,10 @@ use rustc_hir::def_id::LocalDefId;
 use rustc_infer::infer::outlives::env::OutlivesEnvironment;
 use rustc_infer::infer::{InferCtxt, NllRegionVariableOrigin, TyCtxtInferExt as _};
 use rustc_macros::extension;
-use rustc_middle::ty::fold::fold_regions;
 use rustc_middle::ty::visit::TypeVisitableExt;
 use rustc_middle::ty::{
     self, GenericArgKind, GenericArgs, OpaqueHiddenType, OpaqueTypeKey, Ty, TyCtxt, TypeFoldable,
-    TypingMode,
+    TypingMode, fold_regions,
 };
 use rustc_span::Span;
 use rustc_trait_selection::regions::OutlivesEnvironmentBuildExt;

compiler/rustc_borrowck/src/renumber.rs

@@ -2,8 +2,7 @@ use rustc_index::IndexSlice;
 use rustc_infer::infer::NllRegionVariableOrigin;
 use rustc_middle::mir::visit::{MutVisitor, TyContext};
 use rustc_middle::mir::{Body, ConstOperand, Location, Promoted};
-use rustc_middle::ty::fold::fold_regions;
-use rustc_middle::ty::{self, GenericArgsRef, Ty, TyCtxt, TypeFoldable};
+use rustc_middle::ty::{self, GenericArgsRef, Ty, TyCtxt, TypeFoldable, fold_regions};
 use rustc_span::Symbol;
 use tracing::{debug, instrument};
 

compiler/rustc_borrowck/src/type_check/constraint_conversion.rs

@@ -7,8 +7,9 @@ use rustc_infer::infer::{self, InferCtxt, SubregionOrigin};
 use rustc_infer::traits::query::type_op::DeeplyNormalize;
 use rustc_middle::bug;
 use rustc_middle::mir::{ClosureOutlivesSubject, ClosureRegionRequirements, ConstraintCategory};
-use rustc_middle::ty::fold::fold_regions;
-use rustc_middle::ty::{self, GenericArgKind, Ty, TyCtxt, TypeFoldable, TypeVisitableExt};
+use rustc_middle::ty::{
+    self, GenericArgKind, Ty, TyCtxt, TypeFoldable, TypeVisitableExt, fold_regions,
+};
 use rustc_span::Span;
 use rustc_trait_selection::traits::query::type_op::{TypeOp, TypeOpOutput};
 use tracing::{debug, instrument};

compiler/rustc_borrowck/src/type_check/mod.rs

@@ -24,12 +24,11 @@ use rustc_middle::mir::*;
 use rustc_middle::traits::query::NoSolution;
 use rustc_middle::ty::adjustment::PointerCoercion;
 use rustc_middle::ty::cast::CastTy;
-use rustc_middle::ty::fold::fold_regions;
 use rustc_middle::ty::visit::TypeVisitableExt;
 use rustc_middle::ty::{
     self, Binder, CanonicalUserTypeAnnotation, CanonicalUserTypeAnnotations, CoroutineArgsExt,
     Dynamic, GenericArgsRef, OpaqueHiddenType, OpaqueTypeKey, RegionVid, Ty, TyCtxt, UserArgs,
-    UserTypeAnnotationIndex,
+    UserTypeAnnotationIndex, fold_regions,
 };
 use rustc_middle::{bug, span_bug};
 use rustc_mir_dataflow::ResultsCursor;

compiler/rustc_borrowck/src/type_check/opaque_types.rs

@@ -2,10 +2,9 @@ use std::iter;
 
 use rustc_data_structures::fx::FxIndexMap;
 use rustc_middle::span_bug;
-use rustc_middle::ty::fold::fold_regions;
 use rustc_middle::ty::{
     self, GenericArgKind, OpaqueHiddenType, OpaqueTypeKey, Ty, TyCtxt, TypeSuperVisitable,
-    TypeVisitable, TypeVisitableExt, TypeVisitor,
+    TypeVisitable, TypeVisitableExt, TypeVisitor, fold_regions,
 };
 use tracing::{debug, trace};
 

compiler/rustc_borrowck/src/type_check/relate_tys.rs

@@ -10,9 +10,8 @@ use rustc_middle::mir::ConstraintCategory;
 use rustc_middle::span_bug;
 use rustc_middle::traits::ObligationCause;
 use rustc_middle::traits::query::NoSolution;
-use rustc_middle::ty::fold::FnMutDelegate;
 use rustc_middle::ty::relate::combine::{super_combine_consts, super_combine_tys};
-use rustc_middle::ty::{self, Ty, TyCtxt, TypeVisitableExt};
+use rustc_middle::ty::{self, FnMutDelegate, Ty, TyCtxt, TypeVisitableExt};
 use rustc_span::{Span, Symbol, sym};
 use tracing::{debug, instrument};
 

compiler/rustc_borrowck/src/universal_regions.rs

@@ -27,11 +27,10 @@ use rustc_hir::lang_items::LangItem;
 use rustc_index::IndexVec;
 use rustc_infer::infer::NllRegionVariableOrigin;
 use rustc_macros::extension;
-use rustc_middle::ty::fold::{TypeFoldable, fold_regions};
 use rustc_middle::ty::print::with_no_trimmed_paths;
 use rustc_middle::ty::{
     self, GenericArgs, GenericArgsRef, InlineConstArgs, InlineConstArgsParts, RegionVid, Ty,
-    TyCtxt, TypeVisitableExt,
+    TyCtxt, TypeFoldable, TypeVisitableExt, fold_regions,
 };
 use rustc_middle::{bug, span_bug};
 use rustc_span::{ErrorGuaranteed, kw, sym};

compiler/rustc_hir_analysis/src/check/check.rs

@@ -18,18 +18,18 @@ use rustc_middle::hir::nested_filter;
 use rustc_middle::middle::resolve_bound_vars::ResolvedArg;
 use rustc_middle::middle::stability::EvalResult;
 use rustc_middle::ty::error::TypeErrorToStringExt;
-use rustc_middle::ty::fold::{BottomUpFolder, fold_regions};
 use rustc_middle::ty::layout::{LayoutError, MAX_SIMD_LANES};
 use rustc_middle::ty::util::{Discr, IntTypeExt};
 use rustc_middle::ty::{
-    AdtDef, GenericArgKind, RegionKind, TypeSuperVisitable, TypeVisitable, TypeVisitableExt,
+    AdtDef, BottomUpFolder, GenericArgKind, RegionKind, TypeSuperVisitable, TypeVisitable,
+    TypeVisitableExt, fold_regions,
 };
 use rustc_session::lint::builtin::UNINHABITED_STATIC;
 use rustc_trait_selection::error_reporting::InferCtxtErrorExt;
 use rustc_trait_selection::error_reporting::traits::on_unimplemented::OnUnimplementedDirective;
 use rustc_trait_selection::traits;
 use rustc_trait_selection::traits::query::evaluate_obligation::InferCtxtExt;
-use rustc_type_ir::fold::TypeFoldable;
+use rustc_type_ir::TypeFoldable;
 use tracing::{debug, instrument};
 use ty::TypingMode;
 use {rustc_attr_parsing as attr, rustc_hir as hir};

compiler/rustc_hir_analysis/src/check/compare_impl_item.rs

@@ -12,10 +12,9 @@ use rustc_hir::{self as hir, AmbigArg, GenericParamKind, ImplItemKind, intravisi
 use rustc_infer::infer::{self, InferCtxt, TyCtxtInferExt};
 use rustc_infer::traits::util;
 use rustc_middle::ty::error::{ExpectedFound, TypeError};
-use rustc_middle::ty::fold::BottomUpFolder;
 use rustc_middle::ty::util::ExplicitSelf;
 use rustc_middle::ty::{
-    self, GenericArgs, GenericParamDefKind, Ty, TyCtxt, TypeFoldable, TypeFolder,
+    self, BottomUpFolder, GenericArgs, GenericParamDefKind, Ty, TyCtxt, TypeFoldable, TypeFolder,
     TypeSuperFoldable, TypeVisitableExt, TypingMode, Upcast,
 };
 use rustc_middle::{bug, span_bug};

compiler/rustc_hir_analysis/src/collect.rs

@@ -33,9 +33,8 @@ use rustc_infer::infer::{InferCtxt, TyCtxtInferExt};
 use rustc_infer::traits::ObligationCause;
 use rustc_middle::hir::nested_filter;
 use rustc_middle::query::Providers;
-use rustc_middle::ty::fold::fold_regions;
 use rustc_middle::ty::util::{Discr, IntTypeExt};
-use rustc_middle::ty::{self, AdtKind, Const, IsSuggestable, Ty, TyCtxt, TypingMode};
+use rustc_middle::ty::{self, AdtKind, Const, IsSuggestable, Ty, TyCtxt, TypingMode, fold_regions};
 use rustc_middle::{bug, span_bug};
 use rustc_span::{DUMMY_SP, Ident, Span, Symbol, kw, sym};
 use rustc_trait_selection::error_reporting::traits::suggestions::NextTypeParamName;

compiler/rustc_hir_analysis/src/collect/item_bounds.rs

@@ -1,9 +1,9 @@
 use rustc_data_structures::fx::{FxIndexMap, FxIndexSet};
 use rustc_hir as hir;
 use rustc_infer::traits::util;
-use rustc_middle::ty::fold::shift_vars;
 use rustc_middle::ty::{
     self, GenericArgs, Ty, TyCtxt, TypeFoldable, TypeFolder, TypeSuperFoldable, TypeVisitableExt,
+    shift_vars,
 };
 use rustc_middle::{bug, span_bug};
 use rustc_span::Span;

compiler/rustc_hir_analysis/src/collect/type_of.rs

@@ -5,10 +5,9 @@ use rustc_hir::def_id::{DefId, LocalDefId};
 use rustc_hir::intravisit::VisitorExt;
 use rustc_hir::{self as hir, AmbigArg, HirId};
 use rustc_middle::query::plumbing::CyclePlaceholder;
-use rustc_middle::ty::fold::fold_regions;
 use rustc_middle::ty::print::with_forced_trimmed_paths;
 use rustc_middle::ty::util::IntTypeExt;
-use rustc_middle::ty::{self, IsSuggestable, Ty, TyCtxt, TypeVisitableExt};
+use rustc_middle::ty::{self, IsSuggestable, Ty, TyCtxt, TypeVisitableExt, fold_regions};
 use rustc_middle::{bug, span_bug};
 use rustc_span::{DUMMY_SP, Ident, Span};
 

compiler/rustc_hir_analysis/src/constrained_generic_params.rs

@@ -3,7 +3,7 @@ use rustc_middle::bug;
 use rustc_middle::ty::visit::{TypeSuperVisitable, TypeVisitor};
 use rustc_middle::ty::{self, Ty, TyCtxt};
 use rustc_span::Span;
-use rustc_type_ir::fold::TypeFoldable;
+use rustc_type_ir::TypeFoldable;
 use tracing::debug;
 
 #[derive(Clone, PartialEq, Eq, Hash, Debug)]

compiler/rustc_hir_analysis/src/delegation.rs

@@ -7,8 +7,7 @@ use std::assert_matches::debug_assert_matches;
 use rustc_data_structures::fx::FxHashMap;
 use rustc_hir::def::DefKind;
 use rustc_hir::def_id::{DefId, LocalDefId};
-use rustc_middle::ty::fold::{TypeFoldable, TypeFolder, TypeSuperFoldable};
-use rustc_middle::ty::{self, Ty, TyCtxt};
+use rustc_middle::ty::{self, Ty, TyCtxt, TypeFoldable, TypeFolder, TypeSuperFoldable};
 use rustc_span::{ErrorGuaranteed, Span};
 use rustc_type_ir::visit::TypeVisitableExt;
 

compiler/rustc_hir_analysis/src/hir_ty_lowering/dyn_compatibility.rs

@@ -4,9 +4,8 @@ use rustc_errors::struct_span_code_err;
 use rustc_hir as hir;
 use rustc_hir::def::{DefKind, Res};
 use rustc_lint_defs::builtin::UNUSED_ASSOCIATED_TYPE_BOUNDS;
-use rustc_middle::ty::fold::BottomUpFolder;
 use rustc_middle::ty::{
-    self, DynKind, ExistentialPredicateStableCmpExt as _, Ty, TyCtxt, TypeFoldable,
+    self, BottomUpFolder, DynKind, ExistentialPredicateStableCmpExt as _, Ty, TyCtxt, TypeFoldable,
     TypeVisitableExt, Upcast,
 };
 use rustc_span::{ErrorGuaranteed, Span};

compiler/rustc_hir_analysis/src/hir_ty_lowering/mod.rs

@@ -36,11 +36,10 @@ use rustc_infer::infer::{InferCtxt, TyCtxtInferExt};
 use rustc_infer::traits::ObligationCause;
 use rustc_middle::middle::stability::AllowUnstable;
 use rustc_middle::mir::interpret::LitToConstInput;
-use rustc_middle::ty::fold::fold_regions;
 use rustc_middle::ty::print::PrintPolyTraitRefExt as _;
 use rustc_middle::ty::{
     self, Const, GenericArgKind, GenericArgsRef, GenericParamDefKind, ParamEnv, Ty, TyCtxt,
-    TypeVisitableExt, TypingMode,
+    TypeVisitableExt, TypingMode, fold_regions,
 };
 use rustc_middle::{bug, span_bug};
 use rustc_session::lint::builtin::AMBIGUOUS_ASSOCIATED_ITEMS;

compiler/rustc_hir_analysis/src/hir_wf_check.rs

@@ -4,8 +4,7 @@ use rustc_infer::infer::TyCtxtInferExt;
 use rustc_infer::traits::{ObligationCause, WellFormedLoc};
 use rustc_middle::bug;
 use rustc_middle::query::Providers;
-use rustc_middle::ty::fold::fold_regions;
-use rustc_middle::ty::{self, TyCtxt, TypingMode};
+use rustc_middle::ty::{self, TyCtxt, TypingMode, fold_regions};
 use rustc_span::def_id::LocalDefId;
 use rustc_trait_selection::traits::{self, ObligationCtxt};
 use tracing::debug;

compiler/rustc_hir_typeck/src/demand.rs

@@ -6,9 +6,8 @@ use rustc_infer::infer::DefineOpaqueTypes;
 use rustc_middle::bug;
 use rustc_middle::ty::adjustment::AllowTwoPhase;
 use rustc_middle::ty::error::{ExpectedFound, TypeError};
-use rustc_middle::ty::fold::BottomUpFolder;
 use rustc_middle::ty::print::with_no_trimmed_paths;
-use rustc_middle::ty::{self, AssocItem, Ty, TypeFoldable, TypeVisitableExt};
+use rustc_middle::ty::{self, AssocItem, BottomUpFolder, Ty, TypeFoldable, TypeVisitableExt};
 use rustc_span::{DUMMY_SP, Ident, Span, sym};
 use rustc_trait_selection::infer::InferCtxtExt;
 use rustc_trait_selection::traits::ObligationCause;

compiler/rustc_hir_typeck/src/fn_ctxt/_impl.rs

@@ -21,11 +21,10 @@ use rustc_infer::infer::canonical::{Canonical, OriginalQueryValues, QueryRespons
 use rustc_infer::infer::{DefineOpaqueTypes, InferResult};
 use rustc_lint::builtin::SELF_CONSTRUCTOR_FROM_OUTER_ITEM;
 use rustc_middle::ty::adjustment::{Adjust, Adjustment, AutoBorrow, AutoBorrowMutability};
-use rustc_middle::ty::fold::TypeFoldable;
 use rustc_middle::ty::visit::{TypeVisitable, TypeVisitableExt};
 use rustc_middle::ty::{
     self, AdtKind, CanonicalUserType, GenericArgKind, GenericArgsRef, GenericParamDefKind,
-    IsIdentity, Ty, TyCtxt, UserArgs, UserSelfTy,
+    IsIdentity, Ty, TyCtxt, TypeFoldable, UserArgs, UserSelfTy,
 };
 use rustc_middle::{bug, span_bug};
 use rustc_session::lint;

compiler/rustc_hir_typeck/src/method/confirm.rs

@@ -15,9 +15,9 @@ use rustc_middle::traits::ObligationCauseCode;
 use rustc_middle::ty::adjustment::{
     Adjust, Adjustment, AllowTwoPhase, AutoBorrow, AutoBorrowMutability, PointerCoercion,
 };
-use rustc_middle::ty::fold::TypeFoldable;
 use rustc_middle::ty::{
-    self, GenericArgs, GenericArgsRef, GenericParamDefKind, Ty, TyCtxt, TypeVisitableExt, UserArgs,
+    self, GenericArgs, GenericArgsRef, GenericParamDefKind, Ty, TyCtxt, TypeFoldable,
+    TypeVisitableExt, UserArgs,
 };
 use rustc_middle::{bug, span_bug};
 use rustc_span::{DUMMY_SP, Span};

compiler/rustc_hir_typeck/src/writeback.rs

@@ -11,9 +11,10 @@ use rustc_hir::{self as hir, AmbigArg, HirId};
 use rustc_middle::span_bug;
 use rustc_middle::traits::ObligationCause;
 use rustc_middle::ty::adjustment::{Adjust, Adjustment, PointerCoercion};
-use rustc_middle::ty::fold::{TypeFoldable, TypeFolder, fold_regions};
 use rustc_middle::ty::visit::TypeVisitableExt;
-use rustc_middle::ty::{self, Ty, TyCtxt, TypeSuperFoldable};
+use rustc_middle::ty::{
+    self, Ty, TyCtxt, TypeFoldable, TypeFolder, TypeSuperFoldable, fold_regions,
+};
 use rustc_span::{Span, sym};
 use rustc_trait_selection::error_reporting::infer::need_type_info::TypeAnnotationNeeded;
 use rustc_trait_selection::solve;

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

@@ -8,9 +8,9 @@
 use rustc_data_structures::fx::FxHashMap;
 use rustc_index::Idx;
 use rustc_middle::bug;
-use rustc_middle::ty::fold::{TypeFoldable, TypeFolder, TypeSuperFoldable};
 use rustc_middle::ty::{
-    self, BoundVar, GenericArg, InferConst, List, Ty, TyCtxt, TypeFlags, TypeVisitableExt,
+    self, BoundVar, GenericArg, InferConst, List, Ty, TyCtxt, TypeFlags, TypeFoldable, TypeFolder,
+    TypeSuperFoldable, TypeVisitableExt,
 };
 use smallvec::SmallVec;
 use tracing::debug;

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

@@ -8,8 +8,7 @@
 
 use rustc_macros::extension;
 use rustc_middle::bug;
-use rustc_middle::ty::fold::{FnMutDelegate, TypeFoldable};
-use rustc_middle::ty::{self, GenericArgKind, TyCtxt};
+use rustc_middle::ty::{self, FnMutDelegate, GenericArgKind, TyCtxt, TypeFoldable};
 
 use crate::infer::canonical::{Canonical, CanonicalVarValues};
 

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

@@ -24,8 +24,7 @@
 pub use instantiate::CanonicalExt;
 use rustc_index::IndexVec;
 pub use rustc_middle::infer::canonical::*;
-use rustc_middle::ty::fold::TypeFoldable;
-use rustc_middle::ty::{self, GenericArg, List, Ty, TyCtxt};
+use rustc_middle::ty::{self, GenericArg, List, Ty, TyCtxt, TypeFoldable};
 use rustc_span::Span;
 
 use crate::infer::{InferCtxt, RegionVariableOrigin};

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

@@ -13,8 +13,7 @@ use std::iter;
 use rustc_index::{Idx, IndexVec};
 use rustc_middle::arena::ArenaAllocatable;
 use rustc_middle::mir::ConstraintCategory;
-use rustc_middle::ty::fold::TypeFoldable;
-use rustc_middle::ty::{self, BoundVar, GenericArg, GenericArgKind, Ty, TyCtxt};
+use rustc_middle::ty::{self, BoundVar, GenericArg, GenericArgKind, Ty, TyCtxt, TypeFoldable};
 use rustc_middle::{bug, span_bug};
 use tracing::{debug, instrument};
 

compiler/rustc_infer/src/infer/context.rs

@@ -1,10 +1,9 @@
 ///! Definition of `InferCtxtLike` from the librarified type layer.
 use rustc_hir::def_id::DefId;
 use rustc_middle::traits::ObligationCause;
-use rustc_middle::ty::fold::TypeFoldable;
 use rustc_middle::ty::relate::RelateResult;
 use rustc_middle::ty::relate::combine::PredicateEmittingRelation;
-use rustc_middle::ty::{self, Ty, TyCtxt};
+use rustc_middle::ty::{self, Ty, TyCtxt, TypeFoldable};
 use rustc_span::{DUMMY_SP, ErrorGuaranteed, Span};
 
 use super::{BoundRegionConversionTime, InferCtxt, RegionVariableOrigin, SubregionOrigin};

compiler/rustc_infer/src/infer/freshen.rs

@@ -35,8 +35,9 @@ use std::collections::hash_map::Entry;
 
 use rustc_data_structures::fx::FxHashMap;
 use rustc_middle::bug;
-use rustc_middle::ty::fold::TypeFolder;
-use rustc_middle::ty::{self, Ty, TyCtxt, TypeFoldable, TypeSuperFoldable, TypeVisitableExt};
+use rustc_middle::ty::{
+    self, Ty, TyCtxt, TypeFoldable, TypeFolder, TypeSuperFoldable, TypeVisitableExt,
+};
 
 use super::InferCtxt;
 

compiler/rustc_infer/src/infer/lexical_region_resolve/mod.rs

@@ -9,10 +9,9 @@ use rustc_data_structures::graph::implementation::{
 use rustc_data_structures::intern::Interned;
 use rustc_data_structures::unord::UnordSet;
 use rustc_index::{IndexSlice, IndexVec};
-use rustc_middle::ty::fold::{TypeFoldable, fold_regions};
 use rustc_middle::ty::{
     self, ReBound, ReEarlyParam, ReErased, ReError, ReLateParam, RePlaceholder, ReStatic, ReVar,
-    Region, RegionVid, Ty, TyCtxt,
+    Region, RegionVid, Ty, TyCtxt, TypeFoldable, fold_regions,
 };
 use rustc_middle::{bug, span_bug};
 use rustc_span::Span;

compiler/rustc_infer/src/infer/mod.rs

@@ -28,14 +28,12 @@ use rustc_middle::infer::canonical::{CanonicalQueryInput, CanonicalVarValues};
 use rustc_middle::mir::ConstraintCategory;
 use rustc_middle::traits::select;
 use rustc_middle::ty::error::{ExpectedFound, TypeError};
-use rustc_middle::ty::fold::{
-    BoundVarReplacerDelegate, TypeFoldable, TypeFolder, TypeSuperFoldable, fold_regions,
-};
 use rustc_middle::ty::visit::TypeVisitableExt;
 use rustc_middle::ty::{
-    self, ConstVid, FloatVid, GenericArg, GenericArgKind, GenericArgs, GenericArgsRef,
-    GenericParamDefKind, InferConst, IntVid, PseudoCanonicalInput, Ty, TyCtxt, TyVid,
-    TypeVisitable, TypingEnv, TypingMode,
+    self, BoundVarReplacerDelegate, ConstVid, FloatVid, GenericArg, GenericArgKind, GenericArgs,
+    GenericArgsRef, GenericParamDefKind, InferConst, IntVid, PseudoCanonicalInput, Ty, TyCtxt,
+    TyVid, TypeFoldable, TypeFolder, TypeSuperFoldable, TypeVisitable, TypingEnv, TypingMode,
+    fold_regions,
 };
 use rustc_span::{Span, Symbol};
 use snapshot::undo_log::InferCtxtUndoLogs;

compiler/rustc_infer/src/infer/opaque_types/mod.rs

@@ -5,9 +5,9 @@ use rustc_middle::bug;
 use rustc_middle::traits::ObligationCause;
 use rustc_middle::traits::solve::Goal;
 use rustc_middle::ty::error::{ExpectedFound, TypeError};
-use rustc_middle::ty::fold::BottomUpFolder;
 use rustc_middle::ty::{
-    self, OpaqueHiddenType, OpaqueTypeKey, Ty, TyCtxt, TypeFoldable, TypeVisitableExt,
+    self, BottomUpFolder, OpaqueHiddenType, OpaqueTypeKey, Ty, TyCtxt, TypeFoldable,
+    TypeVisitableExt,
 };
 use rustc_span::Span;
 use tracing::{debug, instrument};