@Test
public void testHasErrors() {

    final Collection violations = mock(Collection.class);
    when(violations.isEmpty()).thenReturn(false);
    presenter.violations = violations;
    assertTrue(presenter.hasErrors());
    verify(view, times(0)).clearButtons();
    verify(view, times(0)).addButton(anyString(), anyString(), anyBoolean(), any(Command.class));
    verify(view, times(0)).add(any(IsWidget.class));
    verify(view, times(0)).init(presenter);
    verify(view, times(0)).clearView();
}