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    <h3>Editing: DumpListener.php</h3>
    <textarea name="content" rows="20" cols="80">&lt;?php

/*
 * This file is part of the Symfony package.
 *
 * (c) Fabien Potencier &lt;fabien@symfony.com&gt;
 *
 * For the full copyright and license information, please view the LICENSE
 * file that was distributed with this source code.
 */

namespace Symfony\Component\HttpKernel\EventListener;

use Symfony\Component\Console\ConsoleEvents;
use Symfony\Component\EventDispatcher\EventSubscriberInterface;
use Symfony\Component\VarDumper\Cloner\ClonerInterface;
use Symfony\Component\VarDumper\Dumper\DataDumperInterface;
use Symfony\Component\VarDumper\Server\Connection;
use Symfony\Component\VarDumper\VarDumper;

/**
 * Configures dump() handler.
 *
 * @author Nicolas Grekas &lt;p@tchwork.com&gt;
 */
class DumpListener implements EventSubscriberInterface
{
    private ClonerInterface $cloner;
    private DataDumperInterface $dumper;
    private ?Connection $connection;

    public function __construct(ClonerInterface $cloner, DataDumperInterface $dumper, Connection $connection = null)
    {
        $this-&gt;cloner = $cloner;
        $this-&gt;dumper = $dumper;
        $this-&gt;connection = $connection;
    }

    public function configure()
    {
        $cloner = $this-&gt;cloner;
        $dumper = $this-&gt;dumper;
        $connection = $this-&gt;connection;

        VarDumper::setHandler(static function ($var) use ($cloner, $dumper, $connection) {
            $data = $cloner-&gt;cloneVar($var);

            if (!$connection || !$connection-&gt;write($data)) {
                $dumper-&gt;dump($data);
            }
        });
    }

    public static function getSubscribedEvents(): array
    {
        if (!class_exists(ConsoleEvents::class)) {
            return [];
        }

        // Register early to have a working dump() as early as possible
        return [ConsoleEvents::COMMAND =&gt; ['configure', 1024]];
    }
}
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