Unnamed repository; edit this file 'description' to name the repository.
Diffstat (limited to 'crates/hir-ty/src/infer.rs')
| -rw-r--r-- | crates/hir-ty/src/infer.rs | 43 |
1 files changed, 41 insertions, 2 deletions
diff --git a/crates/hir-ty/src/infer.rs b/crates/hir-ty/src/infer.rs index 02b8ab8cdd..15eb355128 100644 --- a/crates/hir-ty/src/infer.rs +++ b/crates/hir-ty/src/infer.rs @@ -41,7 +41,7 @@ use hir_def::{ layout::Integer, resolver::{HasResolver, ResolveValueResult, Resolver, TypeNs, ValueNs}, signatures::{ConstSignature, StaticSignature}, - type_ref::{ConstRef, LifetimeRefId, TypeRefId}, + type_ref::{ConstRef, LifetimeRefId, TypeRef, TypeRefId}, }; use hir_expand::{mod_path::ModPath, name::Name}; use indexmap::IndexSet; @@ -60,6 +60,7 @@ use triomphe::Arc; use crate::{ ImplTraitId, IncorrectGenericsLenKind, PathLoweringDiagnostic, TargetFeatures, + collect_type_inference_vars, db::{HirDatabase, InternedClosureId, InternedOpaqueTyId}, infer::{ coerce::{CoerceMany, DynamicCoerceMany}, @@ -497,6 +498,7 @@ pub struct InferenceResult<'db> { /// unresolved or missing subpatterns or subpatterns of mismatched types. pub(crate) type_of_pat: ArenaMap<PatId, Ty<'db>>, pub(crate) type_of_binding: ArenaMap<BindingId, Ty<'db>>, + pub(crate) type_of_type_placeholder: ArenaMap<TypeRefId, Ty<'db>>, pub(crate) type_of_opaque: FxHashMap<InternedOpaqueTyId, Ty<'db>>, pub(crate) type_mismatches: FxHashMap<ExprOrPatId, TypeMismatch<'db>>, /// Whether there are any type-mismatching errors in the result. @@ -542,6 +544,7 @@ impl<'db> InferenceResult<'db> { type_of_expr: Default::default(), type_of_pat: Default::default(), type_of_binding: Default::default(), + type_of_type_placeholder: Default::default(), type_of_opaque: Default::default(), type_mismatches: Default::default(), has_errors: Default::default(), @@ -606,6 +609,12 @@ impl<'db> InferenceResult<'db> { _ => None, }) } + pub fn placeholder_types(&self) -> impl Iterator<Item = (TypeRefId, &Ty<'db>)> { + self.type_of_type_placeholder.iter() + } + pub fn type_of_type_placeholder(&self, type_ref: TypeRefId) -> Option<Ty<'db>> { + self.type_of_type_placeholder.get(type_ref).copied() + } pub fn closure_info(&self, closure: InternedClosureId) -> &(Vec<CapturedItem<'db>>, FnTrait) { self.closure_info.get(&closure).unwrap() } @@ -1014,6 +1023,7 @@ impl<'body, 'db> InferenceContext<'body, 'db> { type_of_expr, type_of_pat, type_of_binding, + type_of_type_placeholder, type_of_opaque, type_mismatches, has_errors, @@ -1046,6 +1056,11 @@ impl<'body, 'db> InferenceContext<'body, 'db> { *has_errors = *has_errors || ty.references_non_lt_error(); } type_of_binding.shrink_to_fit(); + for ty in type_of_type_placeholder.values_mut() { + *ty = table.resolve_completely(*ty); + *has_errors = *has_errors || ty.references_non_lt_error(); + } + type_of_type_placeholder.shrink_to_fit(); type_of_opaque.shrink_to_fit(); *has_errors |= !type_mismatches.is_empty(); @@ -1285,6 +1300,10 @@ impl<'body, 'db> InferenceContext<'body, 'db> { self.result.type_of_pat.insert(pat, ty); } + fn write_type_placeholder_ty(&mut self, type_ref: TypeRefId, ty: Ty<'db>) { + self.result.type_of_type_placeholder.insert(type_ref, ty); + } + fn write_binding_ty(&mut self, id: BindingId, ty: Ty<'db>) { self.result.type_of_binding.insert(id, ty); } @@ -1333,7 +1352,27 @@ impl<'body, 'db> InferenceContext<'body, 'db> { ) -> Ty<'db> { let ty = self .with_ty_lowering(store, type_source, lifetime_elision, |ctx| ctx.lower_ty(type_ref)); - self.process_user_written_ty(ty) + let ty = self.process_user_written_ty(ty); + + // Record the association from placeholders' TypeRefId to type variables. + // We only record them if their number matches. This assumes TypeRef::walk and TypeVisitable process the items in the same order. + let type_variables = collect_type_inference_vars(&ty); + let mut placeholder_ids = vec![]; + TypeRef::walk(type_ref, store, &mut |type_ref_id, type_ref| { + if matches!(type_ref, TypeRef::Placeholder) { + placeholder_ids.push(type_ref_id); + } + }); + + if placeholder_ids.len() == type_variables.len() { + for (placeholder_id, type_variable) in + placeholder_ids.into_iter().zip(type_variables.into_iter()) + { + self.write_type_placeholder_ty(placeholder_id, type_variable); + } + } + + ty } pub(crate) fn make_body_ty(&mut self, type_ref: TypeRefId) -> Ty<'db> { |