@Test
public void topicChangedShouldDoNothingIfNewTopicHasOlderTimestamp() {

    final Topic topic = new Topic("Old topic", "Niles", 2000);
    when(controller.getTopic()).thenReturn(topic);
    responder.topicChanged(300, "Older topic", "Niles", 1000); // Older timestamp, must be old topic
    verifyZeroInteractions(messageController, userInterface);
    verifyTopic(topic, "Old topic", "Niles", 2000);
}