'When the message is larger than 512KB it\'s written to disk instead of
just residing in memory. Make sure the different return type of
SecureTemporaryFile is handled as well as BytesIO.'

def test_submit_big_message(self):

    self._new_codename()
    self._dummy_submission()
    resp = self.client.post('/submit', data=dict(msg=('AA' * (1024 * 512)), fh=(StringIO(''), '')), follow_redirects=True)
    self.assertEqual(resp.status_code, 200)
    self.assertIn('Thanks!    We    received    your    message', resp.data)
