async def METHOD_NAME(self, *, stream):
    event = Mock()
    event.ack.return_value = True
    stream._on_stream_event_out = Mock()
    stream._on_message_out = Mock()
    assert await stream.ack(event)
    stream._on_stream_event_out.assert_called_once_with(
        event.message.tp,
        event.message.offset,
        stream,
        event,
    )
    stream._on_message_out.assert_called_once_with(
        event.message.tp,
        event.message.offset,
        event.message,
    )