Nestable\Tests\TestCase::_get_random_parent_id PHP Метод

    protected function _get_random_parent_id(RecursiveArrayIterator $iteratorArray)
    {
        $loop = rand(0, 2);
        $parent_id = false;
        while ($iteratorArray->valid()) {
            if ($iteratorArray->hasChildren()) {
                foreach ($iteratorArray->getChildren() as $key => $value) {
                    if ($parent_id) {
                        break;
                    }
                    if (is_array($value)) {
                        $rand = rand(0, count($value) - 1);
                        if (isset($value[$rand]['parent_id'])) {
                            $parent_id = $value[$rand]['parent_id'];
                        }
                    }
                }
            }
            $iteratorArray->next();
        }
        return $parent_id;
    }