@Test
  public void
      onCustomEventInterstitialClicked_whenInterstitialAdListenerIsNull_shouldNotNotifyListener()
          throws Exception {
    subject.setInterstitialAdListener(null);

    subject.onCustomEventInterstitialClicked();

    verify(interstitialAdListener, never()).onInterstitialClicked(eq(subject));
  }
  @Test
  public void destroy_shouldPreventOnCustomEventInterstitialClickedFromRegisteringClick()
      throws Exception {
    subject.setInterstitialView(interstitialView);
    subject.destroy();

    subject.onCustomEventInterstitialClicked();

    verify(interstitialView, never()).registerClick();
  }
  @Test
  public void onCustomEventInterstitialClicked_shouldRegisterClickAndNotifyListener()
      throws Exception {
    subject.setInterstitialView(interstitialView);

    subject.onCustomEventInterstitialClicked();

    verify(interstitialView).registerClick();
    verify(interstitialAdListener).onInterstitialClicked(eq(subject));
  }