public void testAsMapGetNullKeyAbsent() {
    assertNull(multimap().asMap().get(null));
  }

  @MapFeature.Require(absent = ALLOWS_NULL_KEY_QUERIES)
  public void testAsMapGetNullKeyUnsupported() {
    assertThrows(NullPointerException.class, () -> multimap().asMap().get(null));
  }

  @CollectionSize.Require(absent = ZERO)
  @MapFeature.Require(SUPPORTS_REMOVE)
  public void testAsMapRemove() {