}

  public void testSingletonBuilder() {
    ImmutableMap<String, Integer> map = new Builder<String, Integer>().put("one", 1).buildOrThrow();
    assertMapEquals(map, "one", 1);
  }

  public void testBuilder() {
    ImmutableMap<String, Integer> map =
        new Builder<String, Integer>()
            .put("one", 1)
            .put("two", 2)
            .put("three", 3)
            .put("four", 4)