SortedSet<String> set = copyOf(asIterator("e", "a", "f", "b", "d", "c"));
    assertThat(set).containsExactly("a", "b", "c", "d", "e", "f").inOrder();
  }

  public void testCopyOf_iterator_ordering_dupes() {
    SortedSet<String> set = copyOf(asIterator("e", "a", "e", "f", "b", "b", "d", "a", "c"));
    assertThat(set).containsExactly("a", "b", "c", "d", "e", "f").inOrder();
  }