@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 containsExactlyFailureWithEmptyStringExtra() {
    expectFailureWhenTestingThat(ImmutableMultimap.of("a", "", "", "")).containsExactly("a", "");
    assertFailureKeys("unexpected", "---", "expected", "but was");
    assertFailureValue("unexpected", "{\"\" (empty String)=[\"\" (empty String)]}");
    assertFailureValue("expected", "{a=[\"\" (empty String)]}");
    assertFailureValue("but was", "{a=[], =[]}");
  }