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Diffstat (limited to 'crates/hir-def/src/attrs.rs')
| -rw-r--r-- | crates/hir-def/src/attrs.rs | 35 |
1 files changed, 35 insertions, 0 deletions
diff --git a/crates/hir-def/src/attrs.rs b/crates/hir-def/src/attrs.rs index b560d08492..9da5b98d83 100644 --- a/crates/hir-def/src/attrs.rs +++ b/crates/hir-def/src/attrs.rs @@ -1076,6 +1076,41 @@ impl AttrFlags { }) } } + + pub fn unstable_feature(self, db: &dyn DefDatabase, owner: AttrDefId) -> Option<Symbol> { + if !self.contains(AttrFlags::IS_UNSTABLE) { + return None; + } + + return unstable_feature(db, owner); + + #[salsa::tracked] + fn unstable_feature(db: &dyn DefDatabase, owner: AttrDefId) -> Option<Symbol> { + collect_attrs(db, owner, |attr| { + if let ast::Meta::TokenTreeMeta(attr) = attr + && let path = attr.path() + && path.is1("unstable") + && let Some(tt) = attr.token_tree() + { + let mut tt = TokenTreeChildren::new(&tt); + // Technically the `feature = "..."` always comes first, but it's not a requirement. + while let Some(token) = tt.next() { + if let NodeOrToken::Token(token) = token + && token.text() == "feature" + && let Some(NodeOrToken::Token(eq)) = tt.next() + && eq.kind() == T![=] + && let Some(NodeOrToken::Token(feature)) = tt.next() + && let Some(feature) = ast::String::cast(feature) + && let Ok(feature) = feature.value() + { + return ControlFlow::Break(Symbol::intern(&feature)); + } + } + } + ControlFlow::Continue(()) + }) + } + } } fn merge_repr(this: &mut ReprOptions, other: ReprOptions) { |