### Question:
DecisionNavigatorTreeView implements DecisionNavigatorTreePresenter.View { Element makeTree(final Collection<DecisionNavigatorItem> items) { final Element ulElement = createElement("ul"); if (!Objects.isNull(items)) { items.forEach(item -> { ulElement.appendChild(makeTreeItemElement(item)); }); } return ulElement; } @Inject  DecisionNavigatorTreeView(final HTMLDivElement view,
                                     final HTMLDivElement items,
                                     final ManagedInstance<TreeItem> managedInstance,
                                     final Elemental2DomUtil util); @Override void init(final DecisionNavigatorTreePresenter presenter); @Override HTMLElement getElement(); @Override void clean(); @Override void setup(final List<DecisionNavigatorItem> items); @Override void select(final String uuid); @Override void deselect();  }### Answer:
@Test public void testMakeTree() { final DecisionNavigatorItem item = makeItem("uuid"); final List<DecisionNavigatorItem> items = Collections.singletonList(item); final Element expectedTreeElement = mock(Element.class); final Element treeItemElement = mock(Element.class); doReturn(expectedTreeElement).when(treeView).createElement("ul"); doReturn(treeItemElement).when(treeView).makeTreeItemElement(item); final Element actualTreeElement = treeView.makeTree(items); verify(expectedTreeElement).appendChild(treeItemElement); assertEquals(expectedTreeElement, actualTreeElement); }