From d0e4c679ff1772e7ec0f9ca983ac229ffd3db2dc Mon Sep 17 00:00:00 2001 From: Michael Goulet Date: Sat, 30 Jul 2022 01:33:51 +0000 Subject: Built-in implementation of Tuple trait --- .../rustc_trait_selection/src/traits/project.rs | 6 ++- .../src/traits/select/candidate_assembly.rs | 44 ++++++++++++++++++++++ .../src/traits/select/confirmation.rs | 2 + .../rustc_trait_selection/src/traits/select/mod.rs | 9 +++-- 4 files changed, 56 insertions(+), 5 deletions(-) (limited to 'compiler/rustc_trait_selection') diff --git a/compiler/rustc_trait_selection/src/traits/project.rs b/compiler/rustc_trait_selection/src/traits/project.rs index adf47ece69d..f73dce39764 100644 --- a/compiler/rustc_trait_selection/src/traits/project.rs +++ b/compiler/rustc_trait_selection/src/traits/project.rs @@ -1625,7 +1625,8 @@ fn assemble_candidates_from_impls<'cx, 'tcx>( super::ImplSource::AutoImpl(..) | super::ImplSource::Builtin(..) | super::ImplSource::TraitUpcasting(_) - | super::ImplSource::ConstDestruct(_) => { + | super::ImplSource::ConstDestruct(_) + | super::ImplSource::Tuple => { // These traits have no associated types. selcx.tcx().sess.delay_span_bug( obligation.cause.span, @@ -1700,7 +1701,8 @@ fn confirm_select_candidate<'cx, 'tcx>( | super::ImplSource::Builtin(..) | super::ImplSource::TraitUpcasting(_) | super::ImplSource::TraitAlias(..) - | super::ImplSource::ConstDestruct(_) => { + | super::ImplSource::ConstDestruct(_) + | super::ImplSource::Tuple => { // we don't create Select candidates with this kind of resolution span_bug!( obligation.cause.span, diff --git a/compiler/rustc_trait_selection/src/traits/select/candidate_assembly.rs b/compiler/rustc_trait_selection/src/traits/select/candidate_assembly.rs index 50e9b95a445..4d738a49468 100644 --- a/compiler/rustc_trait_selection/src/traits/select/candidate_assembly.rs +++ b/compiler/rustc_trait_selection/src/traits/select/candidate_assembly.rs @@ -309,6 +309,8 @@ impl<'cx, 'tcx> SelectionContext<'cx, 'tcx> { // User-defined transmutability impls are permitted. self.assemble_candidates_from_impls(obligation, &mut candidates); self.assemble_candidates_for_transmutability(obligation, &mut candidates); + } else if lang_items.tuple_trait() == Some(def_id) { + self.assemble_candidate_for_tuple(obligation, &mut candidates); } else { if lang_items.clone_trait() == Some(def_id) { // Same builtin conditions as `Copy`, i.e., every type which has builtin support @@ -1009,4 +1011,46 @@ impl<'cx, 'tcx> SelectionContext<'cx, 'tcx> { } } } + + fn assemble_candidate_for_tuple( + &mut self, + obligation: &TraitObligation<'tcx>, + candidates: &mut SelectionCandidateSet<'tcx>, + ) { + let self_ty = self.infcx().shallow_resolve(obligation.self_ty().skip_binder()); + match self_ty.kind() { + ty::Tuple(_) => { + candidates.vec.push(TupleCandidate); + } + ty::Infer(ty::TyVar(_)) => { + candidates.ambiguous = true; + } + ty::Bool + | ty::Char + | ty::Int(_) + | ty::Uint(_) + | ty::Float(_) + | ty::Adt(_, _) + | ty::Foreign(_) + | ty::Str + | ty::Array(_, _) + | ty::Slice(_) + | ty::RawPtr(_) + | ty::Ref(_, _, _) + | ty::FnDef(_, _) + | ty::FnPtr(_) + | ty::Dynamic(_, _) + | ty::Closure(_, _) + | ty::Generator(_, _, _) + | ty::GeneratorWitness(_) + | ty::Never + | ty::Projection(_) + | ty::Opaque(_, _) + | ty::Param(_) + | ty::Bound(_, _) + | ty::Error(_) + | ty::Infer(_) + | ty::Placeholder(_) => {} + } + } } diff --git a/compiler/rustc_trait_selection/src/traits/select/confirmation.rs b/compiler/rustc_trait_selection/src/traits/select/confirmation.rs index 2a1099fc82a..ef631167478 100644 --- a/compiler/rustc_trait_selection/src/traits/select/confirmation.rs +++ b/compiler/rustc_trait_selection/src/traits/select/confirmation.rs @@ -126,6 +126,8 @@ impl<'cx, 'tcx> SelectionContext<'cx, 'tcx> { let data = self.confirm_const_destruct_candidate(obligation, def_id)?; ImplSource::ConstDestruct(data) } + + TupleCandidate => ImplSource::Tuple, }; if !obligation.predicate.is_const_if_const() { diff --git a/compiler/rustc_trait_selection/src/traits/select/mod.rs b/compiler/rustc_trait_selection/src/traits/select/mod.rs index c01ac197991..561a3e1c038 100644 --- a/compiler/rustc_trait_selection/src/traits/select/mod.rs +++ b/compiler/rustc_trait_selection/src/traits/select/mod.rs @@ -1618,7 +1618,8 @@ impl<'cx, 'tcx> SelectionContext<'cx, 'tcx> { }; // (*) Prefer `BuiltinCandidate { has_nested: false }`, `PointeeCandidate`, - // `DiscriminantKindCandidate`, and `ConstDestructCandidate` to anything else. + // `DiscriminantKindCandidate`, `ConstDestructCandidate`, and `TupleCandidate` + // to anything else. // // This is a fix for #53123 and prevents winnowing from accidentally extending the // lifetime of a variable. @@ -1638,7 +1639,8 @@ impl<'cx, 'tcx> SelectionContext<'cx, 'tcx> { BuiltinCandidate { has_nested: false } | DiscriminantKindCandidate | PointeeCandidate - | ConstDestructCandidate(_), + | ConstDestructCandidate(_) + | TupleCandidate, _, ) => true, ( @@ -1646,7 +1648,8 @@ impl<'cx, 'tcx> SelectionContext<'cx, 'tcx> { BuiltinCandidate { has_nested: false } | DiscriminantKindCandidate | PointeeCandidate - | ConstDestructCandidate(_), + | ConstDestructCandidate(_) + | TupleCandidate, ) => false, (ParamCandidate(other), ParamCandidate(victim)) => { -- cgit 1.4.1-3-g733a5