### Question:
BottomTabsAttacher { void onTabSelected(ViewController tab) { attachStrategy.onTabSelected(tab); } BottomTabsAttacher(List<ViewController> tabs, BottomTabsPresenter presenter); void destroy();  }### Answer:
@Test public void onTabSelected() { ViewController tab = mock(ViewController.class); uut.onTabSelected(tab); verify(mode).onTabSelected(tab); }