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    <h3>Editing: ServiceValueResolver.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\Controller\ArgumentResolver;

use Psr\Container\ContainerInterface;
use Symfony\Component\DependencyInjection\Exception\RuntimeException;
use Symfony\Component\HttpFoundation\Request;
use Symfony\Component\HttpKernel\Controller\ArgumentValueResolverInterface;
use Symfony\Component\HttpKernel\ControllerMetadata\ArgumentMetadata;

/**
 * Yields a service keyed by _controller and argument name.
 *
 * @author Nicolas Grekas &lt;p@tchwork.com&gt;
 */
final class ServiceValueResolver implements ArgumentValueResolverInterface
{
    private $container;

    public function __construct(ContainerInterface $container)
    {
        $this-&gt;container = $container;
    }

    /**
     * {@inheritdoc}
     */
    public function supports(Request $request, ArgumentMetadata $argument): bool
    {
        $controller = $request-&gt;attributes-&gt;get('_controller');

        if (\is_array($controller) &amp;&amp; \is_callable($controller, true) &amp;&amp; \is_string($controller[0])) {
            $controller = $controller[0].'::'.$controller[1];
        } elseif (!\is_string($controller) || '' === $controller) {
            return false;
        }

        if ('\\' === $controller[0]) {
            $controller = ltrim($controller, '\\');
        }

        if (!$this-&gt;container-&gt;has($controller) &amp;&amp; false !== $i = strrpos($controller, ':')) {
            $controller = substr($controller, 0, $i).strtolower(substr($controller, $i));
        }

        return $this-&gt;container-&gt;has($controller) &amp;&amp; $this-&gt;container-&gt;get($controller)-&gt;has($argument-&gt;getName());
    }

    /**
     * {@inheritdoc}
     */
    public function resolve(Request $request, ArgumentMetadata $argument): iterable
    {
        if (\is_array($controller = $request-&gt;attributes-&gt;get('_controller'))) {
            $controller = $controller[0].'::'.$controller[1];
        }

        if ('\\' === $controller[0]) {
            $controller = ltrim($controller, '\\');
        }

        if (!$this-&gt;container-&gt;has($controller)) {
            $i = strrpos($controller, ':');
            $controller = substr($controller, 0, $i).strtolower(substr($controller, $i));
        }

        try {
            yield $this-&gt;container-&gt;get($controller)-&gt;get($argument-&gt;getName());
        } catch (RuntimeException $e) {
            $what = sprintf('argument $%s of &quot;%s()&quot;', $argument-&gt;getName(), $controller);
            $message = preg_replace('/service &quot;\.service_locator\.[^&quot;]++&quot;/', $what, $e-&gt;getMessage());

            if ($e-&gt;getMessage() === $message) {
                $message = sprintf('Cannot resolve %s: %s', $what, $message);
            }

            $r = new \ReflectionProperty($e, 'message');
            $r-&gt;setAccessible(true);
            $r-&gt;setValue($e, $message);

            throw $e;
        }
    }
}
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