@CanIgnoreReturnValue
  @SuppressWarnings("deprecation") // TODO(b/134064106): design an alternative to no-arg check()
  public final Ordered containsExactly() {
    return check().about(iterableEntries()).that(checkNotNull(actual).entries()).containsExactly();
  }
@Test
  public void containsExactlyNoArg() {
    ImmutableMultimap<Integer, String> actual = ImmutableMultimap.of();

    assertThat(actual).containsExactly();
    assertThat(actual).containsExactly().inOrder();

    expectFailureWhenTestingThat(ImmutableMultimap.of(42, "Answer", 42, "6x7")).containsExactly();
    assertFailureKeys("expected to be empty", "but was");
  }