Try to fix perf regression

astral-sh · Nov 18, 2024 · 1f888e2 · 1f888e2
1 parent 1143efd
commit 1f888e2
Showing 1 changed file with 4 additions and 2 deletions.
diff --git a/crates/red_knot_python_semantic/src/types/narrow.rs b/crates/red_knot_python_semantic/src/types/narrow.rs
@@ -278,8 +278,6 @@ impl<'db> NarrowingConstraintsBuilder<'db> {
             .tuple_windows::<(&ruff_python_ast::Expr, &ruff_python_ast::Expr)>();
         let mut constraints = NarrowingConstraints::default();
         for (op, (left, right)) in std::iter::zip(&**ops, comparator_tuples) {
-            let rhs_ty = inference.expression_ty(right.scoped_expression_id(self.db, scope));
-
             match left {
                 ast::Expr::Name(ast::ExprName {
                     range: _,
@@ -288,6 +286,8 @@ impl<'db> NarrowingConstraintsBuilder<'db> {
                 }) => {
                     // SAFETY: we should always have a symbol for every Name node.
                     let symbol = self.symbols().symbol_id_by_name(id).unwrap();
+                    let rhs_ty =
+                        inference.expression_ty(right.scoped_expression_id(self.db, scope));
 
                     match if is_positive { *op } else { op.negate() } {
                         ast::CmpOp::IsNot => {
@@ -333,6 +333,8 @@ impl<'db> NarrowingConstraintsBuilder<'db> {
                         if let Some(id) = arguments.args[0].as_name_expr().map(|name| &name.id) {
                             let symbol = self.symbols().symbol_id_by_name(id).unwrap();
                             if ast::CmpOp::Is == if is_positive { *op } else { op.negate() } {
+                                let rhs_ty = inference
+                                    .expression_ty(right.scoped_expression_id(self.db, scope));
                                 if rhs_ty.is_class_literal() {
                                     constraints.insert(symbol, rhs_ty.to_instance(self.db));
                                 }