diff --git a/Grammar/python.gram b/Grammar/python.gram index 91d73a9fffd193..6a8bb942fffcc5 100644 --- a/Grammar/python.gram +++ b/Grammar/python.gram @@ -660,7 +660,9 @@ star_named_expression[expr_ty]: | named_expression assignment_expression[expr_ty]: - | a=NAME ':=' ~ b=expression { _PyAST_NamedExpr(CHECK(expr_ty, _PyPegen_set_expr_context(p, a, Store)), b, EXTRA) } + | a=NAME ':=' ~ b=expression { + CHECK_VERSION(expr_ty, 8, "Assignment expressions are", + _PyAST_NamedExpr(CHECK(expr_ty, _PyPegen_set_expr_context(p, a, Store)), b, EXTRA)) } named_expression[expr_ty]: | assignment_expression diff --git a/Lib/test/test_ast.py b/Lib/test/test_ast.py index 225892414b8c19..5d7e4419560b81 100644 --- a/Lib/test/test_ast.py +++ b/Lib/test/test_ast.py @@ -743,6 +743,11 @@ def test_issue40614_feature_version(self): with self.assertRaises(SyntaxError): ast.parse('f"{x=}"', feature_version=(3, 7)) + def test_assignment_expression_feature_version(self): + ast.parse('(x := 0)', feature_version=(3, 8)) + with self.assertRaises(SyntaxError): + ast.parse('(x := 0)', feature_version=(3, 7)) + def test_constant_as_name(self): for constant in "True", "False", "None": expr = ast.Expression(ast.Name(constant, ast.Load()))