Lift `TraitRef` into `rustc_type_ir`

11 files changed, 72 insertions, 46 deletions

diff --git a/compiler/rustc_trait_selection/src/errors.rs b/compiler/rustc_trait_selection/src/errors.rs
index 7228a9ba016..b442446f79b 100644
--- a/compiler/rustc_trait_selection/src/errors.rs
+++ b/compiler/rustc_trait_selection/src/errors.rs
@@ -4,7 +4,7 @@ use rustc_errors::{
     SubdiagMessageOp, Subdiagnostic,
 };
 use rustc_macros::{Diagnostic, Subdiagnostic};
-use rustc_middle::ty::{self, ClosureKind, PolyTraitRef, Ty};
+use rustc_middle::ty::{self, print::PrintTraitRefExt as _, ClosureKind, PolyTraitRef, Ty};
 use rustc_span::{Span, Symbol};
 
 #[derive(Diagnostic)]
diff --git a/compiler/rustc_trait_selection/src/solve/normalizes_to/mod.rs b/compiler/rustc_trait_selection/src/solve/normalizes_to/mod.rs
index f886c588650..454c7a5f00f 100644
--- a/compiler/rustc_trait_selection/src/solve/normalizes_to/mod.rs
+++ b/compiler/rustc_trait_selection/src/solve/normalizes_to/mod.rs
@@ -368,7 +368,7 @@ impl<'tcx> assembly::GoalKind<'tcx> for NormalizesTo<'tcx> {
                 }
             };
         let output_is_sized_pred = tupled_inputs_and_output.map_bound(|(_, output)| {
-            ty::TraitRef::from_lang_item(tcx, LangItem::Sized, DUMMY_SP, [output])
+            ty::TraitRef::new(tcx, tcx.require_lang_item(LangItem::Sized, None), [output])
         });
 
         let pred = tupled_inputs_and_output
@@ -414,7 +414,7 @@ impl<'tcx> assembly::GoalKind<'tcx> for NormalizesTo<'tcx> {
             )?;
         let output_is_sized_pred = tupled_inputs_and_output_and_coroutine.map_bound(
             |AsyncCallableRelevantTypes { output_coroutine_ty: output_ty, .. }| {
-                ty::TraitRef::from_lang_item(tcx, LangItem::Sized, DUMMY_SP, [output_ty])
+                ty::TraitRef::new(tcx, tcx.require_lang_item(LangItem::Sized, None), [output_ty])
             },
         );
 
@@ -576,10 +576,9 @@ impl<'tcx> assembly::GoalKind<'tcx> for NormalizesTo<'tcx> {
                     // and opaque types: If the `self_ty` is `Sized`, then the metadata is `()`.
                     // FIXME(ptr_metadata): This impl overlaps with the other impls and shouldn't
                     // exist. Instead, `Pointee<Metadata = ()>` should be a supertrait of `Sized`.
-                    let sized_predicate = ty::TraitRef::from_lang_item(
+                    let sized_predicate = ty::TraitRef::new(
                         tcx,
-                        LangItem::Sized,
-                        DUMMY_SP,
+                        tcx.require_lang_item(LangItem::Sized, None),
                         [ty::GenericArg::from(goal.predicate.self_ty())],
                     );
                     // FIXME(-Znext-solver=coinductive): Should this be `GoalSource::ImplWhereBound`?
diff --git a/compiler/rustc_trait_selection/src/solve/trait_goals.rs b/compiler/rustc_trait_selection/src/solve/trait_goals.rs
index 0fde9dd4cd6..083cc0aa3c2 100644
--- a/compiler/rustc_trait_selection/src/solve/trait_goals.rs
+++ b/compiler/rustc_trait_selection/src/solve/trait_goals.rs
@@ -16,7 +16,7 @@ use rustc_middle::traits::{BuiltinImplSource, Reveal};
 use rustc_middle::ty::fast_reject::{DeepRejectCtxt, TreatParams};
 use rustc_middle::ty::{self, ToPredicate, Ty, TyCtxt};
 use rustc_middle::ty::{TraitPredicate, TypeVisitableExt};
-use rustc_span::{ErrorGuaranteed, DUMMY_SP};
+use rustc_span::ErrorGuaranteed;
 
 impl<'tcx> assembly::GoalKind<'tcx> for TraitPredicate<'tcx> {
     fn self_ty(self) -> Ty<'tcx> {
@@ -307,7 +307,7 @@ impl<'tcx> assembly::GoalKind<'tcx> for TraitPredicate<'tcx> {
                 }
             };
         let output_is_sized_pred = tupled_inputs_and_output.map_bound(|(_, output)| {
-            ty::TraitRef::from_lang_item(tcx, LangItem::Sized, DUMMY_SP, [output])
+            ty::TraitRef::new(tcx, tcx.require_lang_item(LangItem::Sized, None), [output])
         });
 
         let pred = tupled_inputs_and_output
@@ -346,7 +346,11 @@ impl<'tcx> assembly::GoalKind<'tcx> for TraitPredicate<'tcx> {
             )?;
         let output_is_sized_pred = tupled_inputs_and_output_and_coroutine.map_bound(
             |AsyncCallableRelevantTypes { output_coroutine_ty, .. }| {
-                ty::TraitRef::from_lang_item(tcx, LangItem::Sized, DUMMY_SP, [output_coroutine_ty])
+                ty::TraitRef::new(
+                    tcx,
+                    tcx.require_lang_item(LangItem::Sized, None),
+                    [output_coroutine_ty],
+                )
             },
         );
 
diff --git a/compiler/rustc_trait_selection/src/traits/error_reporting/on_unimplemented.rs b/compiler/rustc_trait_selection/src/traits/error_reporting/on_unimplemented.rs
index 31f9ac1541b..898f83e8748 100644
--- a/compiler/rustc_trait_selection/src/traits/error_reporting/on_unimplemented.rs
+++ b/compiler/rustc_trait_selection/src/traits/error_reporting/on_unimplemented.rs
@@ -10,6 +10,7 @@ use rustc_errors::{codes::*, struct_span_code_err, ErrorGuaranteed};
 use rustc_hir as hir;
 use rustc_hir::def_id::{DefId, LocalDefId};
 use rustc_macros::{extension, LintDiagnostic};
+use rustc_middle::ty::print::PrintTraitRefExt as _;
 use rustc_middle::ty::GenericArgsRef;
 use rustc_middle::ty::{self, GenericParamDefKind, TyCtxt};
 use rustc_parse_format::{ParseMode, Parser, Piece, Position};
diff --git a/compiler/rustc_trait_selection/src/traits/error_reporting/suggestions.rs b/compiler/rustc_trait_selection/src/traits/error_reporting/suggestions.rs
index a687ec0a706..db53d1ebe9d 100644
--- a/compiler/rustc_trait_selection/src/traits/error_reporting/suggestions.rs
+++ b/compiler/rustc_trait_selection/src/traits/error_reporting/suggestions.rs
@@ -538,10 +538,12 @@ impl<'tcx> TypeErrCtxt<'_, 'tcx> {
                             self.tcx,
                             obligation.cause.clone(),
                             obligation.param_env,
-                            ty::TraitRef::from_lang_item(
+                            ty::TraitRef::new(
                                 self.tcx,
-                                hir::LangItem::Sized,
-                                obligation.cause.span,
+                                self.tcx.require_lang_item(
+                                    hir::LangItem::Sized,
+                                    Some(obligation.cause.span),
+                                ),
                                 [base_ty],
                             ),
                         );
@@ -4044,10 +4046,9 @@ impl<'tcx> TypeErrCtxt<'_, 'tcx> {
                         let node = tcx.hir_node_by_def_id(hir.get_parent_item(expr.hir_id).def_id);
 
                         let pred = ty::Binder::dummy(ty::TraitPredicate {
-                            trait_ref: ty::TraitRef::from_lang_item(
+                            trait_ref: ty::TraitRef::new(
                                 tcx,
-                                LangItem::Clone,
-                                span,
+                                tcx.require_lang_item(LangItem::Clone, Some(span)),
                                 [*ty],
                             ),
                             polarity: ty::PredicatePolarity::Positive,
diff --git a/compiler/rustc_trait_selection/src/traits/error_reporting/type_err_ctxt_ext.rs b/compiler/rustc_trait_selection/src/traits/error_reporting/type_err_ctxt_ext.rs
index 0989d499497..b72a4b4d6b6 100644
--- a/compiler/rustc_trait_selection/src/traits/error_reporting/type_err_ctxt_ext.rs
+++ b/compiler/rustc_trait_selection/src/traits/error_reporting/type_err_ctxt_ext.rs
@@ -37,7 +37,9 @@ use rustc_middle::traits::SignatureMismatchData;
 use rustc_middle::ty::abstract_const::NotConstEvaluatable;
 use rustc_middle::ty::error::{ExpectedFound, TypeError};
 use rustc_middle::ty::fold::{BottomUpFolder, TypeFolder, TypeSuperFoldable};
-use rustc_middle::ty::print::{with_forced_trimmed_paths, FmtPrinter, Print};
+use rustc_middle::ty::print::{
+    with_forced_trimmed_paths, FmtPrinter, Print, PrintTraitRefExt as _,
+};
 use rustc_middle::ty::{
     self, SubtypePredicate, ToPolyTraitRef, ToPredicate, TraitRef, Ty, TyCtxt, TypeFoldable,
     TypeVisitable, TypeVisitableExt,
diff --git a/compiler/rustc_trait_selection/src/traits/project.rs b/compiler/rustc_trait_selection/src/traits/project.rs
index 587f2f72207..6b9593bd880 100644
--- a/compiler/rustc_trait_selection/src/traits/project.rs
+++ b/compiler/rustc_trait_selection/src/traits/project.rs
@@ -973,9 +973,12 @@ fn assemble_candidates_from_impls<'cx, 'tcx>(
                 //
                 // NOTE: This should be kept in sync with the similar code in
                 // `rustc_ty_utils::instance::resolve_associated_item()`.
-                let node_item =
-                    specialization_graph::assoc_def(selcx.tcx(), impl_data.impl_def_id, obligation.predicate.def_id)
-                        .map_err(|ErrorGuaranteed { .. }| ())?;
+                let node_item = specialization_graph::assoc_def(
+                    selcx.tcx(),
+                    impl_data.impl_def_id,
+                    obligation.predicate.def_id,
+                )
+                .map_err(|ErrorGuaranteed { .. }| ())?;
 
                 if node_item.is_final() {
                     // Non-specializable items are always projectable.
@@ -1018,7 +1021,8 @@ fn assemble_candidates_from_impls<'cx, 'tcx>(
                     lang_items.async_fn_trait(),
                     lang_items.async_fn_mut_trait(),
                     lang_items.async_fn_once_trait(),
-                ].contains(&Some(trait_ref.def_id))
+                ]
+                .contains(&Some(trait_ref.def_id))
                 {
                     true
                 } else if lang_items.async_fn_kind_helper() == Some(trait_ref.def_id) {
@@ -1031,7 +1035,7 @@ fn assemble_candidates_from_impls<'cx, 'tcx>(
                         true
                     } else {
                         obligation.predicate.args.type_at(0).to_opt_closure_kind().is_some()
-                        && obligation.predicate.args.type_at(1).to_opt_closure_kind().is_some()
+                            && obligation.predicate.args.type_at(1).to_opt_closure_kind().is_some()
                     }
                 } else if lang_items.discriminant_kind_trait() == Some(trait_ref.def_id) {
                     match self_ty.kind() {
@@ -1158,12 +1162,20 @@ fn assemble_candidates_from_impls<'cx, 'tcx>(
                         // Otherwise, type parameters, opaques, and unnormalized projections have
                         // unit metadata if they're known (e.g. by the param_env) to be sized.
                         ty::Param(_) | ty::Alias(..)
-                            if self_ty != tail || selcx.infcx.predicate_must_hold_modulo_regions(
-                                &obligation.with(
-                                    selcx.tcx(),
-                                    ty::TraitRef::from_lang_item(selcx.tcx(), LangItem::Sized, obligation.cause.span(),[self_ty]),
-                                ),
-                            ) =>
+                            if self_ty != tail
+                                || selcx.infcx.predicate_must_hold_modulo_regions(
+                                    &obligation.with(
+                                        selcx.tcx(),
+                                        ty::TraitRef::new(
+                                            selcx.tcx(),
+                                            selcx.tcx().require_lang_item(
+                                                LangItem::Sized,
+                                                Some(obligation.cause.span()),
+                                            ),
+                                            [self_ty],
+                                        ),
+                                    ),
+                                ) =>
                         {
                             true
                         }
@@ -1226,7 +1238,7 @@ fn assemble_candidates_from_impls<'cx, 'tcx>(
                     obligation.cause.span,
                     format!("Cannot project an associated type from `{impl_source:?}`"),
                 );
-                return Err(())
+                return Err(());
             }
         };
 
@@ -1555,10 +1567,9 @@ fn confirm_builtin_candidate<'cx, 'tcx>(
                 // and opaque types: If the `self_ty` is `Sized`, then the metadata is `()`.
                 // FIXME(ptr_metadata): This impl overlaps with the other impls and shouldn't
                 // exist. Instead, `Pointee<Metadata = ()>` should be a supertrait of `Sized`.
-                let sized_predicate = ty::TraitRef::from_lang_item(
+                let sized_predicate = ty::TraitRef::new(
                     tcx,
-                    LangItem::Sized,
-                    obligation.cause.span(),
+                    tcx.require_lang_item(LangItem::Sized, Some(obligation.cause.span())),
                     [self_ty],
                 );
                 obligations.push(obligation.with(tcx, sized_predicate));
diff --git a/compiler/rustc_trait_selection/src/traits/select/confirmation.rs b/compiler/rustc_trait_selection/src/traits/select/confirmation.rs
index 22e0ee38344..e9117b93092 100644
--- a/compiler/rustc_trait_selection/src/traits/select/confirmation.rs
+++ b/compiler/rustc_trait_selection/src/traits/select/confirmation.rs
@@ -735,7 +735,11 @@ impl<'cx, 'tcx> SelectionContext<'cx, 'tcx> {
             output_ty,
             &mut nested,
         );
-        let tr = ty::TraitRef::from_lang_item(self.tcx(), LangItem::Sized, cause.span, [output_ty]);
+        let tr = ty::TraitRef::new(
+            self.tcx(),
+            self.tcx().require_lang_item(LangItem::Sized, Some(cause.span)),
+            [output_ty],
+        );
         nested.push(Obligation::new(self.infcx.tcx, cause, obligation.param_env, tr));
 
         Ok(nested)
@@ -1009,10 +1013,12 @@ impl<'cx, 'tcx> SelectionContext<'cx, 'tcx> {
         } else {
             nested.push(obligation.with(
                 self.tcx(),
-                ty::TraitRef::from_lang_item(
+                ty::TraitRef::new(
                     self.tcx(),
-                    LangItem::AsyncFnKindHelper,
-                    obligation.cause.span,
+                    self.tcx().require_lang_item(
+                        LangItem::AsyncFnKindHelper,
+                        Some(obligation.cause.span),
+                    ),
                     [kind_ty, Ty::from_closure_kind(self.tcx(), goal_kind)],
                 ),
             ));
@@ -1241,10 +1247,9 @@ impl<'cx, 'tcx> SelectionContext<'cx, 'tcx> {
                     .collect();
 
                 // We can only make objects from sized types.
-                let tr = ty::TraitRef::from_lang_item(
+                let tr = ty::TraitRef::new(
                     tcx,
-                    LangItem::Sized,
-                    obligation.cause.span,
+                    tcx.require_lang_item(LangItem::Sized, Some(obligation.cause.span)),
                     [source],
                 );
                 nested.push(predicate_to_obligation(tr.to_predicate(tcx)));
@@ -1474,10 +1479,9 @@ impl<'cx, 'tcx> SelectionContext<'cx, 'tcx> {
                         cause.clone(),
                         obligation.recursion_depth + 1,
                         self_ty.rebind(ty::TraitPredicate {
-                            trait_ref: ty::TraitRef::from_lang_item(
+                            trait_ref: ty::TraitRef::new(
                                 self.tcx(),
-                                LangItem::Destruct,
-                                cause.span,
+                                self.tcx().require_lang_item(LangItem::Destruct, Some(cause.span)),
                                 [nested_ty.into(), host_effect_param],
                             ),
                             polarity: ty::PredicatePolarity::Positive,
@@ -1507,10 +1511,9 @@ impl<'cx, 'tcx> SelectionContext<'cx, 'tcx> {
                 | ty::Infer(_)
                 | ty::Placeholder(_) => {
                     let predicate = self_ty.rebind(ty::TraitPredicate {
-                        trait_ref: ty::TraitRef::from_lang_item(
+                        trait_ref: ty::TraitRef::new(
                             self.tcx(),
-                            LangItem::Destruct,
-                            cause.span,
+                            self.tcx().require_lang_item(LangItem::Destruct, Some(cause.span)),
                             [nested_ty.into(), host_effect_param],
                         ),
                         polarity: ty::PredicatePolarity::Positive,
diff --git a/compiler/rustc_trait_selection/src/traits/select/mod.rs b/compiler/rustc_trait_selection/src/traits/select/mod.rs
index dc005982695..a4b0f8bf0ad 100644
--- a/compiler/rustc_trait_selection/src/traits/select/mod.rs
+++ b/compiler/rustc_trait_selection/src/traits/select/mod.rs
@@ -41,6 +41,7 @@ use rustc_middle::dep_graph::DepNodeIndex;
 use rustc_middle::mir::interpret::ErrorHandled;
 use rustc_middle::ty::_match::MatchAgainstFreshVars;
 use rustc_middle::ty::abstract_const::NotConstEvaluatable;
+use rustc_middle::ty::print::PrintTraitRefExt as _;
 use rustc_middle::ty::relate::TypeRelation;
 use rustc_middle::ty::GenericArgsRef;
 use rustc_middle::ty::{self, PolyProjectionPredicate, ToPredicate};
diff --git a/compiler/rustc_trait_selection/src/traits/specialize/mod.rs b/compiler/rustc_trait_selection/src/traits/specialize/mod.rs
index 390e711a18d..fe3f66f3a3f 100644
--- a/compiler/rustc_trait_selection/src/traits/specialize/mod.rs
+++ b/compiler/rustc_trait_selection/src/traits/specialize/mod.rs
@@ -11,6 +11,7 @@
 
 pub mod specialization_graph;
 use rustc_infer::infer::DefineOpaqueTypes;
+use rustc_middle::ty::print::PrintTraitRefExt as _;
 use specialization_graph::GraphExt;
 
 use crate::errors::NegativePositiveConflict;
diff --git a/compiler/rustc_trait_selection/src/traits/wf.rs b/compiler/rustc_trait_selection/src/traits/wf.rs
index 28ee76f7145..1531e2fa6aa 100644
--- a/compiler/rustc_trait_selection/src/traits/wf.rs
+++ b/compiler/rustc_trait_selection/src/traits/wf.rs
@@ -525,8 +525,11 @@ impl<'a, 'tcx> WfPredicates<'a, 'tcx> {
     fn require_sized(&mut self, subty: Ty<'tcx>, cause: traits::ObligationCauseCode<'tcx>) {
         if !subty.has_escaping_bound_vars() {
             let cause = self.cause(cause);
-            let trait_ref =
-                ty::TraitRef::from_lang_item(self.tcx(), LangItem::Sized, cause.span, [subty]);
+            let trait_ref = ty::TraitRef::new(
+                self.tcx(),
+                self.tcx().require_lang_item(LangItem::Sized, Some(cause.span)),
+                [subty],
+            );
             self.out.push(traits::Obligation::with_depth(
                 self.tcx(),
                 cause,