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    <h3>Editing: ReturnCallback.php</h3>
    <textarea name="content" rows="20" cols="80">&lt;?php declare(strict_types=1);
/*
 * This file is part of PHPUnit.
 *
 * (c) Sebastian Bergmann &lt;sebastian@phpunit.de&gt;
 *
 * For the full copyright and license information, please view the LICENSE
 * file that was distributed with this source code.
 */
namespace PHPUnit\Framework\MockObject\Stub;

use function call_user_func_array;
use function get_class;
use function is_array;
use function is_object;
use function sprintf;
use PHPUnit\Framework\MockObject\Invocation;

/**
 * @internal This class is not covered by the backward compatibility promise for PHPUnit
 */
final class ReturnCallback implements Stub
{
    private $callback;

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

    public function invoke(Invocation $invocation)
    {
        return call_user_func_array($this-&gt;callback, $invocation-&gt;getParameters());
    }

    public function toString(): string
    {
        if (is_array($this-&gt;callback)) {
            if (is_object($this-&gt;callback[0])) {
                $class = get_class($this-&gt;callback[0]);
                $type  = '-&gt;';
            } else {
                $class = $this-&gt;callback[0];
                $type  = '::';
            }

            return sprintf(
                'return result of user defined callback %s%s%s() with the ' .
                'passed arguments',
                $class,
                $type,
                $this-&gt;callback[1],
            );
        }

        return 'return result of user defined callback ' . $this-&gt;callback .
               ' with the passed arguments';
    }
}
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