this.stack = new ArrayDeque<>();
      stack.addLast(expand(root));
    }

    @Override
    @CheckForNull
    protected T computeNext() {
      while (!stack.isEmpty()) {
        PostOrderNode<T> top = stack.getLast();
        if (top.childIterator.hasNext()) {
          T child = top.childIterator.next();
          stack.addLast(expand(child));
        } else {
          stack.removeLast();

    checkCanCreate();

    logger.fine(" Testing: " + name);
    logger.fine("Features: " + formatFeatureSet(features));

    addImpliedFeatures(features);

    logger.fine("Expanded: " + formatFeatureSet(features));

    @SuppressWarnings("rawtypes") // class literals
    List<Class<? extends AbstractTester>> testers = getTesters();

    TestSuite suite = new TestSuite(name);

    checkCanCreate();

    logger.fine(" Testing: " + name);
    logger.fine("Features: " + formatFeatureSet(features));

    addImpliedFeatures(features);

    logger.fine("Expanded: " + formatFeatureSet(features));

    @SuppressWarnings("rawtypes") // class literals
    List<Class<? extends AbstractTester>> testers = getTesters();

    TestSuite suite = new TestSuite(name);