### Question:
FetchCodeReviewsTaskListener implements BackgroundTaskListener { @Override public void onBegin() { } FetchCodeReviewsTaskListener(FetchCodeReviewsTask task, IdeUIInvoker invoker, ReviewDAO reviewDAO,
            boolean showMessages); @Override void onBegin(); @Override void onSuccess(); @Override void onFailure(); @Override void onInterruption();  }### Answer:
@Test public void onBeginDoesNothing() { listener.onBegin(); verifyZeroInteractions(mocks); }