new Builder<String, Integer>().putAll(Collections.<String, Integer>emptyMap()).build();
    assertEquals(Collections.<String, Integer>emptyMap(), map);
  }

  public void testBuilderPutAll() {
    Map<String, Integer> toPut = new LinkedHashMap<>();
    toPut.put("one", 1);
    toPut.put("two", 2);
    toPut.put("three", 3);
    Map<String, Integer> moreToPut = new LinkedHashMap<>();

            .putAll(Collections.<String, Integer>emptyMap())
            .build();
    assertEquals(Collections.<String, Integer>emptyMap(), map);
  }

  public void testBuilderPutAll() {
    Map<String, Integer> toPut = new LinkedHashMap<>();
    toPut.put("one", 1);
    toPut.put("two", 2);
    toPut.put("three", 3);
    Map<String, Integer> moreToPut = new LinkedHashMap<>();