list.set(2, "c2");
    assertThat(tailIterator.next()).isEqualTo("b");
    assertThat(tailIterator.next()).isEqualTo("c2");
    assertFalse(tailIterator.hasNext());
  }

  public void testSkip_structurallyModifiedSkipSome() throws Exception {
    Collection<String> set = new LinkedHashSet<>();
    Collections.addAll(set, "a", "b", "c");
    FluentIterable<String> tail = FluentIterable.from(set).skip(1);
    set.remove("b");

    list.set(2, "C");
    assertThat(tailIterator.next()).isEqualTo("b");
    assertThat(tailIterator.next()).isEqualTo("C");
    assertFalse(tailIterator.hasNext());
  }

  public void testSkip_structurallyModifiedSkipSome() throws Exception {
    Collection<String> set = new LinkedHashSet<>(asList("a", "b", "c"));
    Iterable<String> tail = skip(set, 1);
    set.remove("b");
    set.addAll(newArrayList("A", "B", "C"));