Unnamed repository; edit this file 'description' to name the repository.
Diffstat (limited to 'crates/hir-ty/src/diagnostics/match_check/usefulness.rs')
-rw-r--r--crates/hir-ty/src/diagnostics/match_check/usefulness.rs22
1 files changed, 5 insertions, 17 deletions
diff --git a/crates/hir-ty/src/diagnostics/match_check/usefulness.rs b/crates/hir-ty/src/diagnostics/match_check/usefulness.rs
index 4bb4ff8f10..c4d709a975 100644
--- a/crates/hir-ty/src/diagnostics/match_check/usefulness.rs
+++ b/crates/hir-ty/src/diagnostics/match_check/usefulness.rs
@@ -274,7 +274,6 @@
use std::iter::once;
use hir_def::{AdtId, DefWithBodyId, HasModule, ModuleId};
-use once_cell::unsync::OnceCell;
use smallvec::{smallvec, SmallVec};
use typed_arena::Arena;
@@ -290,7 +289,7 @@ pub(crate) struct MatchCheckCtx<'a, 'p> {
pub(crate) db: &'a dyn HirDatabase,
/// Lowered patterns from arms plus generated by the check.
pub(crate) pattern_arena: &'p Arena<DeconstructedPat<'p>>,
- feature_exhaustive_patterns: OnceCell<bool>,
+ exhaustive_patterns: bool,
}
impl<'a, 'p> MatchCheckCtx<'a, 'p> {
@@ -300,7 +299,9 @@ impl<'a, 'p> MatchCheckCtx<'a, 'p> {
db: &'a dyn HirDatabase,
pattern_arena: &'p Arena<DeconstructedPat<'p>>,
) -> Self {
- Self { module, body, db, pattern_arena, feature_exhaustive_patterns: Default::default() }
+ let def_map = db.crate_def_map(module.krate());
+ let exhaustive_patterns = def_map.is_unstable_feature_enabled("exhaustive_patterns");
+ Self { module, body, db, pattern_arena, exhaustive_patterns }
}
pub(super) fn is_uninhabited(&self, ty: &Ty) -> bool {
@@ -326,20 +327,7 @@ impl<'a, 'p> MatchCheckCtx<'a, 'p> {
// Rust's unstable feature described as "Allows exhaustive pattern matching on types that contain uninhabited types."
pub(super) fn feature_exhaustive_patterns(&self) -> bool {
- *self.feature_exhaustive_patterns.get_or_init(|| {
- let def_map = self.db.crate_def_map(self.module.krate());
- let root_mod = def_map.module_id(def_map.root());
- let rood_attrs = self.db.attrs(root_mod.into());
- let mut nightly_features = rood_attrs
- .by_key("feature")
- .attrs()
- .map(|attr| attr.parse_path_comma_token_tree())
- .flatten()
- .flatten();
- nightly_features.any(
- |feat| matches!(feat.segments(), [name] if name.to_smol_str() == "exhaustive_patterns"),
- )
- })
+ self.exhaustive_patterns
}
}