throw new SomeUncheckedException();
                    }));
    expectUnchanged();
  }

  @MapFeature.Require(absent = SUPPORTS_PUT)
  public void testComputeIfAbsent_unsupportedAbsent() {
    assertThrows(
        UnsupportedOperationException.class,
        () ->
            getMap()
                .computeIfAbsent(
                    k3(),
                    k -> {