A FlowQuery operation which applies an extra filter to consider parent nodes visibility

ConsiderParentsVisibilityOperation.php

<?php
namespace Your\Package\Eel\FlowQueryOperations;

use Neos\ContentRepository\Domain\Projection\Content\TraversableNodeInterface;
use Neos\ContentRepository\Exception\NodeException;
use Neos\Eel\FlowQuery\FlowQuery;
use Neos\Eel\FlowQuery\FlowQueryException;
use Neos\Eel\FlowQuery\Operations\AbstractOperation;
use Neos\Flow\Annotations as Flow;
use Neos\ContentRepository\Domain\Model\NodeInterface;

/**
 * FlowQuery operation which applies an extra filter to consider parent nodes visibility
 * Why is this needed? The .find(...) operation won't respect parent nodes visibility.
 * Use .find(...).considerParentsVisibility() in your Flow query to apply this extra filter.
 */
class ConsiderParentsVisibilityOperation extends AbstractOperation
{
    /**
     * {@inheritdoc}
     */
    protected static $shortName = 'considerParentsVisibility';

    /**
     * {@inheritdoc}
     */
    protected static $priority = 100;

    /**
     * {@inheritdoc}
     *
     * We can only handle CR Nodes.
     */
    public function canEvaluate($context)
    {
        return (!isset($context[0]) || ($context[0] instanceof NodeInterface));
    }

    /**
     * {@inheritdoc}
     *
     * @param array $arguments The arguments for this operation.
     *
     * @return void
     * @throws FlowQueryException
     */
    public function evaluate(FlowQuery $flowQuery, array $arguments)
    {
        if (isset($arguments[0])) {
            throw new FlowQueryException('considerParentsVisibility() expects no arguments', 1644566246);
        }

        $visibleNodes = [];
        foreach ($flowQuery->getContext() as $contextNode) {
            if ($this->hasInvisibleParent($contextNode))
                continue;
            $visibleNodes[] = $contextNode;
        }
        $flowQuery->setContext($visibleNodes);
    }

    /**
     * @param TraversableNodeInterface $contextNode
     * @return boolean
     */
    protected function hasInvisibleParent(TraversableNodeInterface $contextNode)
    {
        $node = $contextNode;
        $result = false;
        do {
            try {
                $node = $node->findParentNode();
            } catch (NodeException $exception) {
                // TODO: Remember invisible path to exit do-while as early as possible for subsequent calls
                if (!$node->isRoot())
                    $result = true;
                break;
            }
        } while (true);
        return $result;
    }
}