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    <h3>Editing: ResponseFormatSame.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\HttpFoundation\Test\Constraint;

use PHPUnit\Framework\Constraint\Constraint;
use Symfony\Component\HttpFoundation\Request;
use Symfony\Component\HttpFoundation\Response;

/**
 * Asserts that the response is in the given format.
 *
 * @author Kévin Dunglas &lt;dunglas@gmail.com&gt;
 */
final class ResponseFormatSame extends Constraint
{
    private Request $request;
    private ?string $format;

    public function __construct(Request $request, ?string $format)
    {
        $this-&gt;request = $request;
        $this-&gt;format = $format;
    }

    public function toString(): string
    {
        return 'format is '.($this-&gt;format ?? 'null');
    }

    /**
     * @param Response $response
     */
    protected function matches($response): bool
    {
        return $this-&gt;format === $this-&gt;request-&gt;getFormat($response-&gt;headers-&gt;get('Content-Type'));
    }

    /**
     * @param Response $response
     */
    protected function failureDescription($response): string
    {
        return 'the Response '.$this-&gt;toString();
    }

    /**
     * @param Response $response
     */
    protected function additionalFailureDescription($response): string
    {
        return (string) $response;
    }
}
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