@CanIgnoreReturnValue
  public final Ordered containsExactly() {
    return containsExactlyEntriesIn(ImmutableMap.of());
  }
@Test
  public void containsExactlyExtraKeyAndMissingKey_failsWithSameToStringForKeys() {
    expectFailureWhenTestingThat(ImmutableMap.of(1L, "jan", 2, "feb"))
        .containsExactly(1, "jan", 2, "feb");
    assertFailureKeys(
        "missing keys",
        "for key",
        "expected value",
        "unexpected keys",
        "for key",
        "unexpected value",
        "---",
        "expected",
        "but was");
    assertFailureValueIndexed("for key", 0, "1 (java.lang.Integer)");
    assertFailureValue("expected value", "jan");
    assertFailureValueIndexed("for key", 1, "1 (java.lang.Long)");
    assertFailureValue("unexpected value", "jan");
  }