diff --git a/compiler/rustc_hir_typeck/src/method/suggest.rs b/compiler/rustc_hir_typeck/src/method/suggest.rs index 8ea0280c5e9be..1512db0116c0d 100644 --- a/compiler/rustc_hir_typeck/src/method/suggest.rs +++ b/compiler/rustc_hir_typeck/src/method/suggest.rs @@ -26,7 +26,6 @@ use rustc_infer::infer::{ RegionVariableOrigin, }; use rustc_middle::infer::unify_key::{ConstVariableOrigin, ConstVariableOriginKind}; -use rustc_middle::traits::util::supertraits; use rustc_middle::ty::fast_reject::DeepRejectCtxt; use rustc_middle::ty::fast_reject::{simplify_type, TreatParams}; use rustc_middle::ty::print::{with_crate_prefix, with_forced_trimmed_paths}; @@ -40,7 +39,7 @@ use rustc_trait_selection::traits::error_reporting::on_unimplemented::OnUnimplem use rustc_trait_selection::traits::error_reporting::on_unimplemented::TypeErrCtxtExt as _; use rustc_trait_selection::traits::query::evaluate_obligation::InferCtxtExt as _; use rustc_trait_selection::traits::{ - FulfillmentError, Obligation, ObligationCause, ObligationCauseCode, + supertraits, FulfillmentError, Obligation, ObligationCause, ObligationCauseCode, }; use std::borrow::Cow; diff --git a/compiler/rustc_infer/src/traits/util.rs b/compiler/rustc_infer/src/traits/util.rs index 93dfbe63bcd1c..3c566e0dd6da6 100644 --- a/compiler/rustc_infer/src/traits/util.rs +++ b/compiler/rustc_infer/src/traits/util.rs @@ -2,7 +2,7 @@ use smallvec::smallvec; use crate::infer::outlives::components::{push_outlives_components, Component}; use crate::traits::{self, Obligation, PredicateObligation}; -use rustc_data_structures::fx::{FxHashSet, FxIndexSet}; +use rustc_data_structures::fx::FxHashSet; use rustc_middle::ty::{self, ToPredicate, Ty, TyCtxt}; use rustc_span::symbol::Ident; use rustc_span::Span; @@ -76,7 +76,13 @@ impl<'tcx> Extend> for PredicateSet<'tcx> { pub struct Elaborator<'tcx, O> { stack: Vec, visited: PredicateSet<'tcx>, - only_self: bool, + mode: Filter, +} + +enum Filter { + All, + OnlySelf, + OnlySelfThatDefines(Ident), } /// Describes how to elaborate an obligation into a sub-obligation. @@ -224,7 +230,7 @@ pub fn elaborate<'tcx, O: Elaboratable<'tcx>>( obligations: impl IntoIterator, ) -> Elaborator<'tcx, O> { let mut elaborator = - Elaborator { stack: Vec::new(), visited: PredicateSet::new(tcx), only_self: false }; + Elaborator { stack: Vec::new(), visited: PredicateSet::new(tcx), mode: Filter::All }; elaborator.extend_deduped(obligations); elaborator } @@ -242,7 +248,13 @@ impl<'tcx, O: Elaboratable<'tcx>> Elaborator<'tcx, O> { /// Filter to only the supertraits of trait predicates, i.e. only the predicates /// that have `Self` as their self type, instead of all implied predicates. pub fn filter_only_self(mut self) -> Self { - self.only_self = true; + self.mode = Filter::OnlySelf; + self + } + + /// Filter to only the supertraits of trait predicates that define the assoc_ty. + pub fn filter_only_self_that_defines(mut self, assoc_ty: Ident) -> Self { + self.mode = Filter::OnlySelfThatDefines(assoc_ty); self } @@ -257,10 +269,12 @@ impl<'tcx, O: Elaboratable<'tcx>> Elaborator<'tcx, O> { return; } // Get predicates implied by the trait, or only super predicates if we only care about self predicates. - let predicates = if self.only_self { - tcx.super_predicates_of(data.def_id()) - } else { - tcx.implied_predicates_of(data.def_id()) + let predicates = match self.mode { + Filter::All => tcx.implied_predicates_of(data.def_id()), + Filter::OnlySelf => tcx.super_predicates_of(data.def_id()), + Filter::OnlySelfThatDefines(ident) => { + tcx.super_predicates_that_define_assoc_item((data.def_id(), ident)) + } }; let obligations = @@ -409,14 +423,14 @@ impl<'tcx, O: Elaboratable<'tcx>> Iterator for Elaborator<'tcx, O> { pub fn supertraits<'tcx>( tcx: TyCtxt<'tcx>, trait_ref: ty::PolyTraitRef<'tcx>, -) -> impl Iterator> { +) -> FilterToTraits>> { elaborate(tcx, [trait_ref.to_predicate(tcx)]).filter_only_self().filter_to_traits() } pub fn transitive_bounds<'tcx>( tcx: TyCtxt<'tcx>, trait_refs: impl Iterator>, -) -> impl Iterator> { +) -> FilterToTraits>> { elaborate(tcx, trait_refs.map(|trait_ref| trait_ref.to_predicate(tcx))) .filter_only_self() .filter_to_traits() @@ -429,31 +443,12 @@ pub fn transitive_bounds<'tcx>( /// `T::Item` and helps to avoid cycle errors (see e.g. #35237). pub fn transitive_bounds_that_define_assoc_item<'tcx>( tcx: TyCtxt<'tcx>, - bounds: impl Iterator>, + trait_refs: impl Iterator>, assoc_name: Ident, -) -> impl Iterator> { - let mut stack: Vec<_> = bounds.collect(); - let mut visited = FxIndexSet::default(); - - std::iter::from_fn(move || { - while let Some(trait_ref) = stack.pop() { - let anon_trait_ref = tcx.anonymize_bound_vars(trait_ref); - if visited.insert(anon_trait_ref) { - let super_predicates = - tcx.super_predicates_that_define_assoc_item((trait_ref.def_id(), assoc_name)); - for (super_predicate, _) in super_predicates.predicates { - let subst_predicate = super_predicate.subst_supertrait(tcx, &trait_ref); - if let Some(binder) = subst_predicate.as_trait_clause() { - stack.push(binder.map_bound(|t| t.trait_ref)); - } - } - - return Some(trait_ref); - } - } - - return None; - }) +) -> FilterToTraits>> { + elaborate(tcx, trait_refs.map(|trait_ref| trait_ref.to_predicate(tcx))) + .filter_only_self_that_defines(assoc_name) + .filter_to_traits() } /////////////////////////////////////////////////////////////////////////// diff --git a/compiler/rustc_lint/src/deref_into_dyn_supertrait.rs b/compiler/rustc_lint/src/deref_into_dyn_supertrait.rs index bc11082d27882..d2d99bc0da87d 100644 --- a/compiler/rustc_lint/src/deref_into_dyn_supertrait.rs +++ b/compiler/rustc_lint/src/deref_into_dyn_supertrait.rs @@ -4,9 +4,10 @@ use crate::{ }; use rustc_hir as hir; -use rustc_middle::{traits::util::supertraits, ty}; +use rustc_middle::ty; use rustc_session::lint::FutureIncompatibilityReason; use rustc_span::sym; +use rustc_trait_selection::traits::supertraits; declare_lint! { /// The `deref_into_dyn_supertrait` lint is output whenever there is a use of the diff --git a/compiler/rustc_middle/src/traits/util.rs b/compiler/rustc_middle/src/traits/util.rs index 05c06efaf1637..b4054f8ff5edd 100644 --- a/compiler/rustc_middle/src/traits/util.rs +++ b/compiler/rustc_middle/src/traits/util.rs @@ -3,9 +3,10 @@ use rustc_data_structures::fx::FxHashSet; use crate::ty::{PolyTraitRef, TyCtxt}; /// Given a PolyTraitRef, get the PolyTraitRefs of the trait's (transitive) supertraits. -/// -/// A simplified version of the same function at `rustc_infer::traits::util::supertraits`. -pub fn supertraits<'tcx>( +/// This only exists in `rustc_middle` because the more powerful elaborator depends on +/// `rustc_infer` for elaborating outlives bounds -- this should only be used for pretty +/// printing. +pub fn supertraits_for_pretty_printing<'tcx>( tcx: TyCtxt<'tcx>, trait_ref: PolyTraitRef<'tcx>, ) -> impl Iterator> { diff --git a/compiler/rustc_middle/src/ty/print/pretty.rs b/compiler/rustc_middle/src/ty/print/pretty.rs index e321f0a7b7f29..4414633934181 100644 --- a/compiler/rustc_middle/src/ty/print/pretty.rs +++ b/compiler/rustc_middle/src/ty/print/pretty.rs @@ -1,6 +1,7 @@ use crate::mir::interpret::{AllocRange, GlobalAlloc, Pointer, Provenance, Scalar}; use crate::query::IntoQueryParam; use crate::query::Providers; +use crate::traits::util::supertraits_for_pretty_printing; use crate::ty::{ self, ConstInt, ParamConst, ScalarInt, Term, TermKind, Ty, TyCtxt, TypeFoldable, TypeSuperFoldable, TypeSuperVisitable, TypeVisitable, TypeVisitableExt, @@ -1166,14 +1167,14 @@ pub trait PrettyPrinter<'tcx>: entry.has_fn_once = true; return; } else if Some(trait_def_id) == self.tcx().lang_items().fn_mut_trait() { - let super_trait_ref = crate::traits::util::supertraits(self.tcx(), trait_ref) + let super_trait_ref = supertraits_for_pretty_printing(self.tcx(), trait_ref) .find(|super_trait_ref| super_trait_ref.def_id() == fn_once_trait) .unwrap(); fn_traits.entry(super_trait_ref).or_default().fn_mut_trait_ref = Some(trait_ref); return; } else if Some(trait_def_id) == self.tcx().lang_items().fn_trait() { - let super_trait_ref = crate::traits::util::supertraits(self.tcx(), trait_ref) + let super_trait_ref = supertraits_for_pretty_printing(self.tcx(), trait_ref) .find(|super_trait_ref| super_trait_ref.def_id() == fn_once_trait) .unwrap();