@Test
public void constructor_hiddenElementSelectors_null_unmodifiable() throws Exception {

	ScreenshotArgument arg = new ScreenshotArgument("scid", new ArrayList<CompareTarget>(), null);
	expected.expect(UnsupportedOperationException.class);
	arg.getHiddenElementSelectors().add(new DomSelector(SelectorType.ID, "id"));
}