doctrine custom hydrator

TestIterateCommand.php

<?php

namespace Lvlp\MapcontBundle\Command;

use Doctrine\ORM\EntityManager;
use Doctrine\ORM\Internal\Hydration\ArrayHydrator;
use Doctrine\ORM\Query;
use Doctrine\ORM\Query\Parser;
use Lvlp\MapcontBundle\Repository\PresetRepository;
use Symfony\Component\Console\Command\Command;
use Symfony\Component\Console\Input\InputInterface;
use Symfony\Component\Console\Output\OutputInterface;

class TestIterateCommand extends Command
{
    /**
     * @var PresetRepository
     */
    private $repository;

    /**
     * @var EntityManager
     */
    private $entityManager;

    /**
     * @param PresetRepository $repository
     * @param EntityManager $entityManager
     */
    public function __construct(PresetRepository $repository, EntityManager $entityManager)
    {
        parent::__construct();

        $this->repository = $repository;
        $this->entityManager = $entityManager;
    }

    /**
     * {@inheritdoc}
     */
    protected function configure()
    {
        $this->setName('mapcont:test:iterate');
    }

    public function execute(InputInterface $input, OutputInterface $output)
    {
        $queryBuilder = $this->repository->getIterate();
        $queryBuilder->orderBy('origin_type.id', 'ASC');

        $query = $queryBuilder->getQuery();

        $parser = new Parser($query);

        $hydrator = new ArrayHydrator($this->entityManager);
        $resultSetMapping = $parser->parse()->getResultSetMapping();

        foreach ($this->getResult($query) as $row) {
            $stmt = new HydratorMockStatement($row);

            $hydrator->hydrateAll($stmt, $resultSetMapping)[0];
            //echo json_encode();
        }

        echo 'After ' . memory_get_usage(true) / 1024 / 1024 . PHP_EOL;

       //var_dump($result);
    }

    private function getResult(Query $query)
    {
        echo 'Before ' . memory_get_usage(true) / 1024 / 1024 . PHP_EOL;

        $data = $this->entityManager->getConnection()
            ->executeQuery($query->getSQL(), $query->getParameters()->toArray());

        echo 'After ' . memory_get_usage(true) / 1024 / 1024 . PHP_EOL;

        $rowResult = [];
        $currentPrimaryKeyValue = null;

        while (($result = $data->fetch()) || count($rowResult) > 0) {
            if ($result === false) {
                yield $rowResult;
                break;
            }

            $primaryKeyValue = $result['id0'];

            if ($currentPrimaryKeyValue !== null && $primaryKeyValue != $currentPrimaryKeyValue) {
                yield $rowResult;

                $rowResult = [];
            }

            $rowResult[] = $result;
            $currentPrimaryKeyValue = $primaryKeyValue;
        }
    }
}