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    <h3>Editing: ArgumentResolver.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;

use Symfony\Component\HttpFoundation\Request;
use Symfony\Component\HttpKernel\Controller\ArgumentResolver\DefaultValueResolver;
use Symfony\Component\HttpKernel\Controller\ArgumentResolver\RequestAttributeValueResolver;
use Symfony\Component\HttpKernel\Controller\ArgumentResolver\RequestValueResolver;
use Symfony\Component\HttpKernel\Controller\ArgumentResolver\SessionValueResolver;
use Symfony\Component\HttpKernel\Controller\ArgumentResolver\VariadicValueResolver;
use Symfony\Component\HttpKernel\ControllerMetadata\ArgumentMetadataFactory;
use Symfony\Component\HttpKernel\ControllerMetadata\ArgumentMetadataFactoryInterface;

/**
 * Responsible for resolving the arguments passed to an action.
 *
 * @author Iltar van der Berg &lt;kjarli@gmail.com&gt;
 */
final class ArgumentResolver implements ArgumentResolverInterface
{
    private $argumentMetadataFactory;
    private $argumentValueResolvers;

    /**
     * @param iterable&lt;mixed, ArgumentValueResolverInterface&gt; $argumentValueResolvers
     */
    public function __construct(?ArgumentMetadataFactoryInterface $argumentMetadataFactory = null, iterable $argumentValueResolvers = [])
    {
        $this-&gt;argumentMetadataFactory = $argumentMetadataFactory ?? new ArgumentMetadataFactory();
        $this-&gt;argumentValueResolvers = $argumentValueResolvers ?: self::getDefaultArgumentValueResolvers();
    }

    /**
     * {@inheritdoc}
     */
    public function getArguments(Request $request, callable $controller): array
    {
        $arguments = [];

        foreach ($this-&gt;argumentMetadataFactory-&gt;createArgumentMetadata($controller) as $metadata) {
            foreach ($this-&gt;argumentValueResolvers as $resolver) {
                if (!$resolver-&gt;supports($request, $metadata)) {
                    continue;
                }

                $resolved = $resolver-&gt;resolve($request, $metadata);

                $atLeastOne = false;
                foreach ($resolved as $append) {
                    $atLeastOne = true;
                    $arguments[] = $append;
                }

                if (!$atLeastOne) {
                    throw new \InvalidArgumentException(sprintf('&quot;%s::resolve()&quot; must yield at least one value.', get_debug_type($resolver)));
                }

                // continue to the next controller argument
                continue 2;
            }

            $representative = $controller;

            if (\is_array($representative)) {
                $representative = sprintf('%s::%s()', \get_class($representative[0]), $representative[1]);
            } elseif (\is_object($representative)) {
                $representative = \get_class($representative);
            }

            throw new \RuntimeException(sprintf('Controller &quot;%s&quot; requires that you provide a value for the &quot;$%s&quot; argument. Either the argument is nullable and no null value has been provided, no default value has been provided or because there is a non optional argument after this one.', $representative, $metadata-&gt;getName()));
        }

        return $arguments;
    }

    /**
     * @return iterable&lt;int, ArgumentValueResolverInterface&gt;
     */
    public static function getDefaultArgumentValueResolvers(): iterable
    {
        return [
            new RequestAttributeValueResolver(),
            new RequestValueResolver(),
            new SessionValueResolver(),
            new DefaultValueResolver(),
            new VariadicValueResolver(),
        ];
    }
}
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