def test_invalid_pointer(self):
        self.login("hamlet@zulip.com")
        self.assertEqual(get_user_profile_by_email("hamlet@zulip.com").pointer, -1)
        result = self.client_put("/json/users/me/pointer", {"pointer": "foo"})
        self.assert_json_error(result, "Bad value for 'pointer': foo")
        self.assertEqual(get_user_profile_by_email("hamlet@zulip.com").pointer, -1)
Posting json to /json/users/me/pointer with an invalid pointer returns a 400 and error
dataset/ETHPy150Open zulip/zulip/zerver/tests/test_unread.py/PointerTest.test_invalid_pointer