'Assert that if the value given by ``nbytes`` is greater than the actual
size of the output buffer passed to :py:obj:`Connection.recv_into`, the
behavior is as if no value was given for ``nbytes`` at all.'

def _really_doesnt_overfill_test(self, factory):

    output_buffer = factory(5)
    (server, client) = self._loopback()
    server.send(b('abcdefghij'))
    self.assertEqual(client.recv_into(output_buffer, 50), 5)
    self.assertEqual(output_buffer, bytearray(b('abcde')))
    rest = client.recv(5)
    self.assertEqual(b('fghij'), rest)
