Auto merge of #92805 - BoxyUwU:revert-lazy-anon-const-substs, r=lcnr

partially revertish `lazily "compute" anon const default substs`

reverts #87280 except for some of the changes around `ty::Unevaluated` having a visitor and a generic for promoted
why revert: <rust-lang/rust#92805 (comment)>

r? `@lcnr`

Author: bors

clippy_lints/src/escape.rs

@@ -175,8 +175,7 @@ impl<'a, 'tcx> Delegate<'tcx> for EscapeDelegate<'a, 'tcx> {
                 // skip if there is a `self` parameter binding to a type
                 // that contains `Self` (i.e.: `self: Box<Self>`), see #4804
                 if let Some(trait_self_ty) = self.trait_self_ty {
-                    if map.name(cmt.hir_id) == kw::SelfLower && contains_ty(self.cx.tcx, cmt.place.ty(), trait_self_ty)
-                    {
+                    if map.name(cmt.hir_id) == kw::SelfLower && contains_ty(cmt.place.ty(), trait_self_ty) {
                         return;
                     }
                 }

clippy_lints/src/let_underscore.rs

@@ -124,7 +124,7 @@ impl<'tcx> LateLintPass<'tcx> for LetUnderscore {
             if let Some(init) = local.init;
             then {
                 let init_ty = cx.typeck_results().expr_ty(init);
-                let contains_sync_guard = init_ty.walk(cx.tcx).any(|inner| match inner.unpack() {
+                let contains_sync_guard = init_ty.walk().any(|inner| match inner.unpack() {
                     GenericArgKind::Type(inner_ty) => {
                         SYNC_GUARD_PATHS.iter().any(|path| match_type(cx, inner_ty, path))
                     },

clippy_lints/src/loops/same_item_push.rs

@@ -49,7 +49,7 @@ pub(super) fn check<'tcx>(
         if same_item_push_visitor.should_lint();
         if let Some((vec, pushed_item)) = same_item_push_visitor.vec_push;
         let vec_ty = cx.typeck_results().expr_ty(vec);
-        let ty = vec_ty.walk(cx.tcx).nth(1).unwrap().expect_ty();
+        let ty = vec_ty.walk().nth(1).unwrap().expect_ty();
         if cx
             .tcx
             .lang_items()

clippy_lints/src/methods/mod.rs

@@ -2129,10 +2129,10 @@ impl<'tcx> LateLintPass<'tcx> for Methods {
 
             // walk the return type and check for Self (this does not check associated types)
             if let Some(self_adt) = self_ty.ty_adt_def() {
-                if contains_adt_constructor(cx.tcx, ret_ty, self_adt) {
+                if contains_adt_constructor(ret_ty, self_adt) {
                     return;
                 }
-            } else if contains_ty(cx.tcx, ret_ty, self_ty) {
+            } else if contains_ty(ret_ty, self_ty) {
                 return;
             }
 
@@ -2143,10 +2143,10 @@ impl<'tcx> LateLintPass<'tcx> for Methods {
                     if let ty::PredicateKind::Projection(projection_predicate) = predicate.kind().skip_binder() {
                         // walk the associated type and check for Self
                         if let Some(self_adt) = self_ty.ty_adt_def() {
-                            if contains_adt_constructor(cx.tcx, projection_predicate.ty, self_adt) {
+                            if contains_adt_constructor(projection_predicate.ty, self_adt) {
                                 return;
                             }
-                        } else if contains_ty(cx.tcx, projection_predicate.ty, self_ty) {
+                        } else if contains_ty(projection_predicate.ty, self_ty) {
                             return;
                         }
                     }
@@ -2195,7 +2195,7 @@ impl<'tcx> LateLintPass<'tcx> for Methods {
             if let TraitItemKind::Fn(_, _) = item.kind;
             let ret_ty = return_ty(cx, item.hir_id());
             let self_ty = TraitRef::identity(cx.tcx, item.def_id.to_def_id()).self_ty().skip_binder();
-            if !contains_ty(cx.tcx, ret_ty, self_ty);
+            if !contains_ty(ret_ty, self_ty);
 
             then {
                 span_lint(

clippy_lints/src/needless_pass_by_value.rs

@@ -118,7 +118,7 @@ impl<'tcx> LateLintPass<'tcx> for NeedlessPassByValue {
         let fn_def_id = cx.tcx.hir().local_def_id(hir_id);
 
         let preds = traits::elaborate_predicates(cx.tcx, cx.param_env.caller_bounds().iter())
-            .filter(|p| !p.is_global(cx.tcx))
+            .filter(|p| !p.is_global())
             .filter_map(|obligation| {
                 // Note that we do not want to deal with qualified predicates here.
                 match obligation.predicate.kind().no_bound_vars() {

clippy_lints/src/non_copy_const.rs

@@ -188,7 +188,10 @@ fn is_value_unfrozen_expr<'tcx>(cx: &LateContext<'tcx>, hir_id: HirId, def_id: D
 
     let result = cx.tcx.const_eval_resolve(
         cx.param_env,
-        ty::Unevaluated::new(ty::WithOptConstParam::unknown(def_id), substs),
+        ty::Unevaluated::new(
+            ty::WithOptConstParam::unknown(def_id),
+            substs,
+        ),
         None,
     );
     is_value_unfrozen_raw(cx, result, ty)

clippy_lints/src/non_send_fields_in_send_ty.rs

@@ -111,7 +111,7 @@ impl<'tcx> LateLintPass<'tcx> for NonSendFieldInSendTy {
                                 non_send_fields.push(NonSendField {
                                     def: field_def,
                                     ty: field_ty,
-                                    generic_params: collect_generic_params(cx, field_ty),
+                                    generic_params: collect_generic_params(field_ty),
                                 })
                             }
                         }
@@ -171,8 +171,8 @@ impl<'tcx> NonSendField<'tcx> {
 
 /// Given a type, collect all of its generic parameters.
 /// Example: `MyStruct<P, Box<Q, R>>` => `vec![P, Q, R]`
-fn collect_generic_params<'tcx>(cx: &LateContext<'tcx>, ty: Ty<'tcx>) -> Vec<Ty<'tcx>> {
-    ty.walk(cx.tcx)
+fn collect_generic_params(ty: Ty<'_>) -> Vec<Ty<'_>> {
+    ty.walk()
         .filter_map(|inner| match inner.unpack() {
             GenericArgKind::Type(inner_ty) => Some(inner_ty),
             _ => None,
@@ -226,7 +226,7 @@ fn ty_allowed_with_raw_pointer_heuristic<'tcx>(cx: &LateContext<'tcx>, ty: Ty<'t
 
 /// Checks if the type contains any pointer-like types in substs (including nested ones)
 fn contains_pointer_like<'tcx>(cx: &LateContext<'tcx>, target_ty: Ty<'tcx>) -> bool {
-    for ty_node in target_ty.walk(cx.tcx) {
+    for ty_node in target_ty.walk() {
         if let GenericArgKind::Type(inner_ty) = ty_node.unpack() {
             match inner_ty.kind() {
                 ty::RawPtr(_) => {

clippy_lints/src/redundant_clone.rs

@@ -14,7 +14,7 @@ use rustc_middle::mir::{
     visit::{MutatingUseContext, NonMutatingUseContext, PlaceContext, Visitor as _},
     Mutability,
 };
-use rustc_middle::ty::{self, fold::TypeVisitor, Ty, TyCtxt};
+use rustc_middle::ty::{self, fold::TypeVisitor, Ty};
 use rustc_mir_dataflow::{Analysis, AnalysisDomain, CallReturnPlaces, GenKill, GenKillAnalysis, ResultsCursor};
 use rustc_session::{declare_lint_pass, declare_tool_lint};
 use rustc_span::source_map::{BytePos, Span};
@@ -575,7 +575,7 @@ impl<'a, 'tcx> mir::visit::Visitor<'tcx> for PossibleBorrowerVisitor<'a, 'tcx> {
                 self.possible_borrower.add(borrowed.local, lhs);
             },
             other => {
-                if ContainsRegion(self.cx.tcx)
+                if ContainsRegion
                     .visit_ty(place.ty(&self.body.local_decls, self.cx.tcx).ty)
                     .is_continue()
                 {
@@ -624,7 +624,7 @@ impl<'a, 'tcx> mir::visit::Visitor<'tcx> for PossibleBorrowerVisitor<'a, 'tcx> {
                 .flat_map(HybridBitSet::iter)
                 .collect();
 
-            if ContainsRegion(self.cx.tcx)
+            if ContainsRegion
                 .visit_ty(self.body.local_decls[*dest].ty)
                 .is_break()
             {
@@ -703,15 +703,12 @@ impl<'a, 'tcx> mir::visit::Visitor<'tcx> for PossibleOriginVisitor<'a, 'tcx> {
     }
 }
 
-struct ContainsRegion<'tcx>(TyCtxt<'tcx>);
+struct ContainsRegion;
 
-impl<'tcx> TypeVisitor<'tcx> for ContainsRegion<'tcx> {
+impl TypeVisitor<'_> for ContainsRegion {
     type BreakTy = ();
-    fn tcx_for_anon_const_substs(&self) -> Option<TyCtxt<'tcx>> {
-        Some(self.0)
-    }
 
-    fn visit_region(&mut self, _: ty::Region<'tcx>) -> ControlFlow<Self::BreakTy> {
+    fn visit_region(&mut self, _: ty::Region<'_>) -> ControlFlow<Self::BreakTy> {
         ControlFlow::BREAK
     }
 }

clippy_lints/src/returns.rs

@@ -301,7 +301,7 @@ impl<'tcx> Visitor<'tcx> for BorrowVisitor<'_, 'tcx> {
                 .fn_sig(def_id)
                 .output()
                 .skip_binder()
-                .walk(self.cx.tcx)
+                .walk()
                 .any(|arg| matches!(arg.unpack(), GenericArgKind::Lifetime(_)));
         }
 

clippy_lints/src/self_named_constructors.rs

@@ -63,10 +63,10 @@ impl<'tcx> LateLintPass<'tcx> for SelfNamedConstructors {
 
         // Ensure method is constructor-like
         if let Some(self_adt) = self_ty.ty_adt_def() {
-            if !contains_adt_constructor(cx.tcx, ret_ty, self_adt) {
+            if !contains_adt_constructor(ret_ty, self_adt) {
                 return;
             }
-        } else if !contains_ty(cx.tcx, ret_ty, self_ty) {
+        } else if !contains_ty(ret_ty, self_ty) {
             return;
         }