### Question:
DecisionNavigatorObserver { Optional<DecisionNavigatorItem> getActiveParent() { return Optional.ofNullable(getTreePresenter().getActiveParent()); }  void init(final DecisionNavigatorPresenter presenter);  }### Answer:
@Test public void testGetActiveParent() { final DecisionNavigatorItem expectedItem = makeItem(uuid); when(treePresenter.getActiveParent()).thenReturn(expectedItem); observer.init(presenter); final DecisionNavigatorItem actualItem = observer.getActiveParent().get(); assertEquals(expectedItem, actualItem); }