@Test
public void nickShouldChangeNickNameAndShowSystemMessageAndUpdateUserInterface() throws CommandException {

    doAnswer(withSetNickNameOnMe()).when(controller).changeMyNick(anyString());
    parser.parse("/nick NewNick");
    verify(messageController).showSystemMessage("You changed nick to NewNick");
    verify(controller).changeMyNick("NewNick");
    verify(userInterface).showTopic();
}