diff -r 478b4e9551fa Lib/test/test_defaultdict.py --- a/Lib/test/test_defaultdict.py Sun Dec 04 23:56:30 2011 +0100 +++ b/Lib/test/test_defaultdict.py Mon Dec 05 23:13:52 2011 +1000 @@ -171,6 +171,14 @@ finally: os.remove(tfn) + def test_callable_arg(self): + try: + d1 = defaultdict({}) + except TypeError, err: + self.assertEqual(err.args[0], 'first argument must be callable') + else: + self.fail("expected TypeError") + def test_main(): test_support.run_unittest(TestDefaultDict)