stk.push(new ActivationFrame("activation", Optional.of(target)));
            try {
                return super.transformActivation(target);
            } finally {
                stk.pop();
            }
        }

        @Override
        protected Activation.Builder transformActivation_ActiveByDefault(

    }

    @Override
    public void push(E e) {
      synchronized (mutex) {
        delegate().push(e);
      }
    }

    @Override
    public E pop() {
      synchronized (mutex) {
        return delegate().pop();
      }
    }

    @Override
    public Iterator<E> descendingIterator() {
      synchronized (mutex) {
        return delegate().descendingIterator();

    journalBkpFile = cacheDir / DiskLruCache.JOURNAL_FILE_BACKUP
    createNewCache()
  }

  @AfterEach fun tearDown() {
    while (!toClose.isEmpty()) {
      toClose.pop().close()
    }
    taskFaker.close()

    (filesystem.delegate as? FakeFileSystem)?.checkNoOpenFiles()
  }

  @ParameterizedTest
  @ArgumentsSource(FileSystemParamProvider::class)