fix: use try_scoped_use_id

Author: mtshiba

crates/red_knot_python_semantic/src/semantic_index/ast_ids.rs

@@ -43,6 +43,10 @@ impl AstIds {
     fn use_id(&self, key: impl Into<ExpressionNodeKey>) -> ScopedUseId {
         self.uses_map[&key.into()]
     }
+
+    fn try_use_id(&self, key: impl Into<ExpressionNodeKey>) -> Option<ScopedUseId> {
+        self.uses_map.get(&key.into()).copied()
+    }
 }
 
 fn ast_ids<'db>(db: &'db dyn Db, scope: ScopeId) -> &'db AstIds {
@@ -56,27 +60,43 @@ pub struct ScopedUseId;
 pub trait HasScopedUseId {
     /// Returns the ID that uniquely identifies the use in `scope`.
     fn scoped_use_id(&self, db: &dyn Db, scope: ScopeId) -> ScopedUseId;
+    fn try_scoped_use_id(&self, db: &dyn Db, scope: ScopeId) -> Option<ScopedUseId>;
 }
 
 impl HasScopedUseId for ast::Identifier {
     fn scoped_use_id(&self, db: &dyn Db, scope: ScopeId) -> ScopedUseId {
         let ast_ids = ast_ids(db, scope);
         ast_ids.use_id(self)
     }
+
+    fn try_scoped_use_id(&self, db: &dyn Db, scope: ScopeId) -> Option<ScopedUseId> {
+        let ast_ids = ast_ids(db, scope);
+        ast_ids.try_use_id(self)
+    }
 }
 
 impl HasScopedUseId for ast::ExprName {
     fn scoped_use_id(&self, db: &dyn Db, scope: ScopeId) -> ScopedUseId {
         let expression_ref = ExprRef::from(self);
         expression_ref.scoped_use_id(db, scope)
     }
+
+    fn try_scoped_use_id(&self, db: &dyn Db, scope: ScopeId) -> Option<ScopedUseId> {
+        let expression_ref = ExprRef::from(self);
+        expression_ref.try_scoped_use_id(db, scope)
+    }
 }
 
 impl HasScopedUseId for ast::ExprRef<'_> {
     fn scoped_use_id(&self, db: &dyn Db, scope: ScopeId) -> ScopedUseId {
         let ast_ids = ast_ids(db, scope);
         ast_ids.use_id(*self)
     }
+
+    fn try_scoped_use_id(&self, db: &dyn Db, scope: ScopeId) -> Option<ScopedUseId> {
+        let ast_ids = ast_ids(db, scope);
+        ast_ids.try_use_id(*self)
+    }
 }
 
 /// Uniquely identifies an [`ast::Expr`] in a [`crate::semantic_index::symbol::FileScopeId`].

crates/red_knot_python_semantic/src/types/infer.rs

@@ -4888,13 +4888,16 @@ impl<'db> TypeInferenceBuilder<'db> {
             let db = self.db();
             let scope = self.scope();
 
-            let use_id = name.scoped_use_id(db, scope);
-            let use_def = use_def_map(db, scope);
-            let mut bindings = use_def.bindings_at_use(use_id);
-            let binding = bindings.next().unwrap();
-            binding
-                .narrowing_constraint
-                .narrow(db, ty, DefinitionTarget::Expr(target))
+            if let Some(use_id) = name.try_scoped_use_id(db, scope) {
+                let use_def = use_def_map(db, scope);
+                let mut bindings = use_def.bindings_at_use(use_id);
+                let binding = bindings.next().unwrap();
+                binding
+                    .narrowing_constraint
+                    .narrow(db, ty, DefinitionTarget::Expr(target))
+            } else {
+                ty
+            }
         } else {
             ty
         }