UserEditorScreen { void showError(final String message) { errorPopupPresenter.showMessage(message); }  @PostConstruct void init(); @OnStartup void onStartup(final PlaceRequest placeRequest); @OnOpen void onOpen(); @OnMayClose boolean onMayClose(); @OnClose void onClose(); @WorkbenchPartTitle String getTitle(); @WorkbenchPartView IsWidget getWidget(); @WorkbenchContextId String getMyContextRef(); static final String SCREEN_ID; static final String USER_ID; static final String ADD_USER; }
@Test public void testShowError() { tested.showError("error"); verify(errorPopupPresenter, times(1)).showMessage("error"); }