@Test
public void testContainsAll() throws Exception {

  ObservableList<String> list = new ObservableList<>();
  list.add("A");
  list.add("B");
  list.add("C");
  assertThat(list.containsAll(ImmutableSet.of("A", "B", "C"))).isTrue();
  assertThat(list.containsAll(ImmutableSet.of("X", "Y", "Z"))).isFalse();
}