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    <h3>Editing: ErrorController.php</h3>
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/*
 * 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\Controller;

use Symfony\Component\ErrorHandler\ErrorRenderer\ErrorRendererInterface;
use Symfony\Component\HttpFoundation\Request;
use Symfony\Component\HttpFoundation\Response;
use Symfony\Component\HttpKernel\Exception\HttpException;
use Symfony\Component\HttpKernel\HttpKernelInterface;

/**
 * Renders error or exception pages from a given FlattenException.
 *
 * @author Yonel Ceruto &lt;yonelceruto@gmail.com&gt;
 * @author Matthias Pigulla &lt;mp@webfactory.de&gt;
 */
class ErrorController
{
    private $kernel;
    private $controller;
    private $errorRenderer;

    public function __construct(HttpKernelInterface $kernel, $controller, ErrorRendererInterface $errorRenderer)
    {
        $this-&gt;kernel = $kernel;
        $this-&gt;controller = $controller;
        $this-&gt;errorRenderer = $errorRenderer;
    }

    public function __invoke(\Throwable $exception): Response
    {
        $exception = $this-&gt;errorRenderer-&gt;render($exception);

        return new Response($exception-&gt;getAsString(), $exception-&gt;getStatusCode(), $exception-&gt;getHeaders());
    }

    public function preview(Request $request, int $code): Response
    {
        /*
         * This Request mimics the parameters set by
         * \Symfony\Component\HttpKernel\EventListener\ErrorListener::duplicateRequest, with
         * the additional &quot;showException&quot; flag.
         */
        $subRequest = $request-&gt;duplicate(null, null, [
            '_controller' =&gt; $this-&gt;controller,
            'exception' =&gt; new HttpException($code, 'This is a sample exception.'),
            'logger' =&gt; null,
            'showException' =&gt; false,
        ]);

        return $this-&gt;kernel-&gt;handle($subRequest, HttpKernelInterface::SUB_REQUEST);
    }
}
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