@Test
  public void newWithoutAll() {
    ImmutableBag<String> bag = this.newBag();
    ImmutableBag<String> withoutAll = bag.newWithoutAll(UnifiedSet.newSet(this.newBag()));
    Assert.assertEquals(Bags.immutable.of(), withoutAll);

    ImmutableBag<String> newBag =
        bag.newWithAll(Lists.fixedSize.of("0", "0", "0")).newWithoutAll(Lists.fixedSize.of("0"));

    Assert.assertEquals(0, newBag.occurrencesOf("0"));
  }