^^&&^^

Edit File: AbstractConfigurator.php

<?php

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

namespace Symfony\Component\DependencyInjection\Loader\Configurator;

use Symfony\Component\DependencyInjection\Argument\ArgumentInterface;
use Symfony\Component\DependencyInjection\Definition;
use Symfony\Component\DependencyInjection\Exception\InvalidArgumentException;
use Symfony\Component\DependencyInjection\Parameter;
use Symfony\Component\DependencyInjection\Reference;
use Symfony\Component\ExpressionLanguage\Expression;

abstract class AbstractConfigurator
{
    public const FACTORY = 'unknown';

/** @internal */
    protected $definition;

public function __call($method, $args)
    {
        if (method_exists($this, 'set'.$method)) {
            return $this->{'set'.$method}(...$args);
        }

throw new \BadMethodCallException(sprintf('Call to undefined method "%s::%s()".', static::class, $method));
    }

public function __sleep()
    {
        throw new \BadMethodCallException('Cannot serialize '.__CLASS__);
    }

public function __wakeup()
    {
        throw new \BadMethodCallException('Cannot unserialize '.__CLASS__);
    }

/**
     * Checks that a value is valid, optionally replacing Definition and Reference configurators by their configure value.
     *
     * @param mixed $value
     * @param bool  $allowServices whether Definition and Reference are allowed; by default, only scalars and arrays are
     *
     * @return mixed the value, optionally cast to a Definition/Reference
     */
    public static function processValue($value, $allowServices = false)
    {
        if (\is_array($value)) {
            foreach ($value as $k => $v) {
                $value[$k] = static::processValue($v, $allowServices);
            }

return $value;
        }

if ($value instanceof ReferenceConfigurator) {
            return new Reference($value->id, $value->invalidBehavior);
        }

if ($value instanceof InlineServiceConfigurator) {
            $def = $value->definition;
            $value->definition = null;

return $def;
        }

if ($value instanceof self) {
            throw new InvalidArgumentException(sprintf('"%s()" can be used only at the root of service configuration files.', $value::FACTORY));
        }

switch (true) {
            case null === $value:
            case is_scalar($value):
                return $value;

case $value instanceof ArgumentInterface:
            case $value instanceof Definition:
            case $value instanceof Expression:
            case $value instanceof Parameter:
            case $value instanceof Reference:
                if ($allowServices) {
                    return $value;
                }
        }

throw new InvalidArgumentException(sprintf('Cannot use values of type "%s" in service configuration files.', \is_object($value) ? \get_class($value) : \gettype($value)));
    }
}