assertThat(map.get("five")).isNull();
    assertThat(map.entrySet())
        .containsExactly(mapEntry("one", 3), mapEntry("two", 3), mapEntry("three", 5))
        .inOrder();
  }

  public void testAsMapReadsThrough() {
    Set<String> strings = new LinkedHashSet<>();
    Collections.addAll(strings, "one", "two", "three");
    Map<String, Integer> map = Maps.asMap(strings, LENGTH_FUNCTION);