}

  // In principle, it would be nice to apply these two tests to keys with existing values, too.

  @MapFeature.Require(value = SUPPORTS_PUT, absent = ALLOWS_NULL_VALUES)
  public void testPutAllNullValueNullLast_unsupported() {
    int size = getNumElements();

    assertThrows(
        NullPointerException.class, () -> multimap().putAll(k3(), Lists.newArrayList(v3(), null)));