bendns' repos / rust-analyzer
Unnamed repository; edit this file 'description' to name the repository.
Diffstat (limited to 'crates/hir-ty/src/inhabitedness.rs')
-rw-r--r--crates/hir-ty/src/inhabitedness.rs23
1 files changed, 19 insertions, 4 deletions
diff --git a/crates/hir-ty/src/inhabitedness.rs b/crates/hir-ty/src/inhabitedness.rs
index e0c3279d3f..e81a5e3c31 100644
--- a/crates/hir-ty/src/inhabitedness.rs
+++ b/crates/hir-ty/src/inhabitedness.rs
@@ -7,17 +7,24 @@ use chalk_ir::{
};
use hir_def::{AdtId, EnumVariantId, ModuleId, VariantId, visibility::Visibility};
use rustc_hash::FxHashSet;
+use triomphe::Arc;
use crate::{
- Binders, Interner, Substitution, Ty, TyKind, consteval::try_const_usize, db::HirDatabase,
+ AliasTy, Binders, Interner, Substitution, TraitEnvironment, Ty, TyKind,
+ consteval::try_const_usize, db::HirDatabase,
};
// FIXME: Turn this into a query, it can be quite slow
/// Checks whether a type is visibly uninhabited from a particular module.
-pub(crate) fn is_ty_uninhabited_from(db: &dyn HirDatabase, ty: &Ty, target_mod: ModuleId) -> bool {
+pub(crate) fn is_ty_uninhabited_from(
+ db: &dyn HirDatabase,
+ ty: &Ty,
+ target_mod: ModuleId,
+ env: Arc<TraitEnvironment>,
+) -> bool {
let _p = tracing::info_span!("is_ty_uninhabited_from", ?ty).entered();
let mut uninhabited_from =
- UninhabitedFrom { target_mod, db, max_depth: 500, recursive_ty: FxHashSet::default() };
+ UninhabitedFrom { target_mod, db, max_depth: 500, recursive_ty: FxHashSet::default(), env };
let inhabitedness = ty.visit_with(&mut uninhabited_from, DebruijnIndex::INNERMOST);
inhabitedness == BREAK_VISIBLY_UNINHABITED
}
@@ -29,11 +36,12 @@ pub(crate) fn is_enum_variant_uninhabited_from(
variant: EnumVariantId,
subst: &Substitution,
target_mod: ModuleId,
+ env: Arc<TraitEnvironment>,
) -> bool {
let _p = tracing::info_span!("is_enum_variant_uninhabited_from").entered();
let mut uninhabited_from =
- UninhabitedFrom { target_mod, db, max_depth: 500, recursive_ty: FxHashSet::default() };
+ UninhabitedFrom { target_mod, db, max_depth: 500, recursive_ty: FxHashSet::default(), env };
let inhabitedness = uninhabited_from.visit_variant(variant.into(), subst);
inhabitedness == BREAK_VISIBLY_UNINHABITED
}
@@ -44,6 +52,7 @@ struct UninhabitedFrom<'a> {
// guard for preventing stack overflow in non trivial non terminating types
max_depth: usize,
db: &'a dyn HirDatabase,
+ env: Arc<TraitEnvironment>,
}
const CONTINUE_OPAQUELY_INHABITED: ControlFlow<VisiblyUninhabited> = Continue(());
@@ -78,6 +87,12 @@ impl TypeVisitor<Interner> for UninhabitedFrom<'_> {
Some(0) | None => CONTINUE_OPAQUELY_INHABITED,
Some(1..) => item_ty.super_visit_with(self, outer_binder),
},
+ TyKind::Alias(AliasTy::Projection(projection)) => {
+ // FIXME: I think this currently isn't used for monomorphized bodies, so there is no need to handle
+ // `TyKind::AssociatedType`, but perhaps in the future it will.
+ let normalized = self.db.normalize_projection(projection.clone(), self.env.clone());
+ self.visit_ty(&normalized, outer_binder)
+ }
_ => CONTINUE_OPAQUELY_INHABITED,
};
self.recursive_ty.remove(ty);