}

  public void testContains_nonNullSetNo() {
    Iterable<String> set = newHashSet("a", "b");
    assertFalse(FluentIterable.from(set).contains("c"));
  }

  public void testContains_nonNullIterableYes() {
    Iterable<String> set = iterable("a", null, "b");
    assertTrue(FluentIterable.from(set).contains("b"));
  }

  public void testContains_nonNullIterableNo() {