Iterator<String> iterator = Lists.newArrayList("yam", "bam", "jam", "ham").iterator();
    assertThat(Iterators.toString(iterator)).isEqualTo("[yam, bam, jam, ham]");
  }

  public void testToStringWithNull() {
    Iterator<@Nullable String> iterator =
        Lists.<@Nullable String>newArrayList("hello", null, "world").iterator();
    assertThat(Iterators.toString(iterator)).isEqualTo("[hello, null, world]");
  }