}

  public void testFirst_emptyIterable() {
    Set<String> set = new HashSet<>();
    assertThat(FluentIterable.from(set).first()).isAbsent();
  }

  public void testLast_list() {
    List<String> list = Lists.newArrayList("a", "b", "c");
    assertThat(FluentIterable.from(list).last()).hasValue("c");
  }

  public void testLast_null() {