From 8c2670026a4c864a67a06bab654e203ed068f021 Mon Sep 17 00:00:00 2001 From: Jonas Schievink Date: Tue, 28 Apr 2020 00:40:32 +0200 Subject: Complete assoc. items on type parameters --- crates/ra_hir_ty/src/lib.rs | 3 +- crates/ra_hir_ty/src/lower.rs | 144 ++++++++++++++++++++++++++---------------- 2 files changed, 90 insertions(+), 57 deletions(-) (limited to 'crates/ra_hir_ty') diff --git a/crates/ra_hir_ty/src/lib.rs b/crates/ra_hir_ty/src/lib.rs index a8ef32ec5..341a18683 100644 --- a/crates/ra_hir_ty/src/lib.rs +++ b/crates/ra_hir_ty/src/lib.rs @@ -66,7 +66,8 @@ pub use autoderef::autoderef; pub use infer::{InferTy, InferenceResult}; pub use lower::CallableDef; pub use lower::{ - callable_item_sig, ImplTraitLoweringMode, TyDefId, TyLoweringContext, ValueTyDefId, + associated_types, callable_item_sig, ImplTraitLoweringMode, TyDefId, TyLoweringContext, + ValueTyDefId, }; pub use traits::{InEnvironment, Obligation, ProjectionPredicate, TraitEnvironment}; diff --git a/crates/ra_hir_ty/src/lower.rs b/crates/ra_hir_ty/src/lower.rs index a6f893037..67e5c1ccd 100644 --- a/crates/ra_hir_ty/src/lower.rs +++ b/crates/ra_hir_ty/src/lower.rs @@ -17,9 +17,9 @@ use hir_def::{ path::{GenericArg, Path, PathSegment, PathSegments}, resolver::{HasResolver, Resolver, TypeNs}, type_ref::{TypeBound, TypeRef}, - AdtId, AssocContainerId, ConstId, EnumId, EnumVariantId, FunctionId, GenericDefId, HasModule, - ImplId, LocalFieldId, Lookup, StaticId, StructId, TraitId, TypeAliasId, TypeParamId, UnionId, - VariantId, + AdtId, AssocContainerId, AssocItemId, ConstId, EnumId, EnumVariantId, FunctionId, GenericDefId, + HasModule, ImplId, LocalFieldId, Lookup, StaticId, StructId, TraitId, TypeAliasId, TypeParamId, + UnionId, VariantId, }; use ra_arena::map::ArenaMap; use ra_db::CrateId; @@ -34,6 +34,7 @@ use crate::{ Binders, BoundVar, DebruijnIndex, FnSig, GenericPredicate, PolyFnSig, ProjectionPredicate, ProjectionTy, Substs, TraitEnvironment, TraitRef, Ty, TypeCtor, TypeWalk, }; +use hir_expand::name::Name; #[derive(Debug)] pub struct TyLoweringContext<'a> { @@ -383,61 +384,37 @@ impl Ty { res: Option, segment: PathSegment<'_>, ) -> Ty { - let traits_from_env: Vec<_> = match res { - Some(TypeNs::SelfType(impl_id)) => match ctx.db.impl_trait(impl_id) { - None => return Ty::Unknown, - Some(trait_ref) => vec![trait_ref.value], - }, - Some(TypeNs::GenericParam(param_id)) => { - let predicates = ctx.db.generic_predicates_for_param(param_id); - let mut traits_: Vec<_> = predicates - .iter() - .filter_map(|pred| match &pred.value { - GenericPredicate::Implemented(tr) => Some(tr.clone()), - _ => None, - }) - .collect(); - // Handle `Self::Type` referring to own associated type in trait definitions - if let GenericDefId::TraitId(trait_id) = param_id.parent { - let generics = generics(ctx.db.upcast(), trait_id.into()); - if generics.params.types[param_id.local_id].provenance - == TypeParamProvenance::TraitSelf - { - let trait_ref = TraitRef { - trait_: trait_id, - substs: Substs::bound_vars(&generics, DebruijnIndex::INNERMOST), - }; - traits_.push(trait_ref); - } + if let Some(res) = res { + let ty = associated_types(ctx.db, res, move |name, t, associated_ty| { + if name == segment.name { + let substs = match ctx.type_param_mode { + TypeParamLoweringMode::Placeholder => { + // if we're lowering to placeholders, we have to put + // them in now + let s = Substs::type_params( + ctx.db, + ctx.resolver + .generic_def() + .expect("there should be generics if there's a generic param"), + ); + t.substs.clone().subst_bound_vars(&s) + } + TypeParamLoweringMode::Variable => t.substs.clone(), + }; + // FIXME handle type parameters on the segment + return Some(Ty::Projection(ProjectionTy { + associated_ty, + parameters: substs, + })); } - traits_ - } - _ => return Ty::Unknown, - }; - let traits = traits_from_env.into_iter().flat_map(|t| all_super_trait_refs(ctx.db, t)); - for t in traits { - if let Some(associated_ty) = - ctx.db.trait_data(t.trait_).associated_type_by_name(&segment.name) - { - let substs = match ctx.type_param_mode { - TypeParamLoweringMode::Placeholder => { - // if we're lowering to placeholders, we have to put - // them in now - let s = Substs::type_params( - ctx.db, - ctx.resolver - .generic_def() - .expect("there should be generics if there's a generic param"), - ); - t.substs.subst_bound_vars(&s) - } - TypeParamLoweringMode::Variable => t.substs, - }; - // FIXME handle (forbid) type parameters on the segment - return Ty::Projection(ProjectionTy { associated_ty, parameters: substs }); - } + + None + }); + + ty.unwrap_or(Ty::Unknown) + } else { + Ty::Unknown } - Ty::Unknown } fn from_hir_path_inner( @@ -694,6 +671,61 @@ pub fn callable_item_sig(db: &dyn HirDatabase, def: CallableDef) -> PolyFnSig { } } +pub fn associated_types( + db: &dyn HirDatabase, + res: TypeNs, + mut cb: impl FnMut(&Name, &TraitRef, TypeAliasId) -> Option, +) -> Option { + let traits_from_env: Vec<_> = match res { + TypeNs::SelfType(impl_id) => match db.impl_trait(impl_id) { + None => vec![], + Some(trait_ref) => vec![trait_ref.value], + }, + TypeNs::GenericParam(param_id) => { + let predicates = db.generic_predicates_for_param(param_id); + let mut traits_: Vec<_> = predicates + .iter() + .filter_map(|pred| match &pred.value { + GenericPredicate::Implemented(tr) => Some(tr.clone()), + _ => None, + }) + .collect(); + // Handle `Self::Type` referring to own associated type in trait definitions + if let GenericDefId::TraitId(trait_id) = param_id.parent { + let generics = generics(db.upcast(), trait_id.into()); + if generics.params.types[param_id.local_id].provenance + == TypeParamProvenance::TraitSelf + { + let trait_ref = TraitRef { + trait_: trait_id, + substs: Substs::bound_vars(&generics, DebruijnIndex::INNERMOST), + }; + traits_.push(trait_ref); + } + } + traits_ + } + _ => vec![], + }; + + for t in traits_from_env.into_iter().flat_map(move |t| all_super_trait_refs(db, t)) { + let data = db.trait_data(t.trait_); + + for (name, assoc_id) in &data.items { + match assoc_id { + AssocItemId::TypeAliasId(alias) => { + if let Some(result) = cb(name, &t, *alias) { + return Some(result); + } + } + AssocItemId::FunctionId(_) | AssocItemId::ConstId(_) => {} + } + } + } + + None +} + /// Build the type of all specific fields of a struct or enum variant. pub(crate) fn field_types_query( db: &dyn HirDatabase, -- cgit v1.2.3