}

  public void testSkip_skipNone() {
    Collection<String> set = ImmutableSet.of("a", "b");
    assertEquals(newArrayList("a", "b"), newArrayList(skip(set, 0)));
  }

  public void testSkip_skipNoneList() {
    Collection<String> list = newArrayList("a", "b");
    assertEquals(newArrayList("a", "b"), newArrayList(skip(list, 0)));
  }

  public void testSkip_removal() {