Method test_namedtuple_errors

Lib/test/test_typing.py:8365–8405

(self)

                self.assertIsInstance(struct(), struct)

    def test_namedtuple_errors(self):
        with self.assertRaises(TypeError):
            NamedTuple.__new__()
        with self.assertRaisesRegex(TypeError, "object is not iterable"):
            NamedTuple('Name', None)

        with self.assertRaisesRegex(
            TypeError,
            "missing 2 required positional arguments"
        ):
            NamedTuple()

        with self.assertRaisesRegex(
            TypeError,
            "takes 2 positional arguments but 3 were given"
        ):
            NamedTuple('Emp', [('name', str)], None)

        with self.assertRaisesRegex(
            ValueError,
            "Field names cannot start with an underscore"
        ):
            NamedTuple('Emp', [('_name', str)])

        with self.assertRaisesRegex(
            TypeError,
            "got some positional-only arguments passed as keyword arguments"
        ):
            NamedTuple(typename='Emp', name=str, id=int)

        with self.assertRaisesRegex(
            TypeError,
            "got an unexpected keyword argument"
        ):
            NamedTuple('Name', [('x', int)], y=str)

        with self.assertRaisesRegex(
            TypeError,
            "got an unexpected keyword argument"
        ):
            NamedTuple('Name', [], y=str)

    def test_copy_and_pickle(self):
        global Emp  # pickle wants to reference the class by name