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    <h3>Editing: VarDumper.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\VarDumper;

use Symfony\Component\HttpFoundation\Request;
use Symfony\Component\HttpFoundation\RequestStack;
use Symfony\Component\HttpKernel\Debug\FileLinkFormatter;
use Symfony\Component\VarDumper\Caster\ReflectionCaster;
use Symfony\Component\VarDumper\Cloner\VarCloner;
use Symfony\Component\VarDumper\Dumper\CliDumper;
use Symfony\Component\VarDumper\Dumper\ContextProvider\CliContextProvider;
use Symfony\Component\VarDumper\Dumper\ContextProvider\RequestContextProvider;
use Symfony\Component\VarDumper\Dumper\ContextProvider\SourceContextProvider;
use Symfony\Component\VarDumper\Dumper\ContextualizedDumper;
use Symfony\Component\VarDumper\Dumper\HtmlDumper;
use Symfony\Component\VarDumper\Dumper\ServerDumper;

// Load the global dump() function
require_once __DIR__.'/Resources/functions/dump.php';

/**
 * @author Nicolas Grekas &lt;p@tchwork.com&gt;
 */
class VarDumper
{
    /**
     * @var callable|null
     */
    private static $handler;

    public static function dump($var)
    {
        if (null === self::$handler) {
            self::register();
        }

        return (self::$handler)($var);
    }

    /**
     * @return callable|null
     */
    public static function setHandler(?callable $callable = null)
    {
        $prevHandler = self::$handler;

        // Prevent replacing the handler with expected format as soon as the env var was set:
        if (isset($_SERVER['VAR_DUMPER_FORMAT'])) {
            return $prevHandler;
        }

        self::$handler = $callable;

        return $prevHandler;
    }

    private static function register(): void
    {
        $cloner = new VarCloner();
        $cloner-&gt;addCasters(ReflectionCaster::UNSET_CLOSURE_FILE_INFO);

        $format = $_SERVER['VAR_DUMPER_FORMAT'] ?? null;
        switch (true) {
            case 'html' === $format:
                $dumper = new HtmlDumper();
                break;
            case 'cli' === $format:
                $dumper = new CliDumper();
                break;
            case 'server' === $format:
            case $format &amp;&amp; 'tcp' === parse_url($format, \PHP_URL_SCHEME):
                $host = 'server' === $format ? $_SERVER['VAR_DUMPER_SERVER'] ?? '127.0.0.1:9912' : $format;
                $dumper = \in_array(\PHP_SAPI, ['cli', 'phpdbg'], true) ? new CliDumper() : new HtmlDumper();
                $dumper = new ServerDumper($host, $dumper, self::getDefaultContextProviders());
                break;
            default:
                $dumper = \in_array(\PHP_SAPI, ['cli', 'phpdbg'], true) ? new CliDumper() : new HtmlDumper();
        }

        if (!$dumper instanceof ServerDumper) {
            $dumper = new ContextualizedDumper($dumper, [new SourceContextProvider()]);
        }

        self::$handler = function ($var) use ($cloner, $dumper) {
            $dumper-&gt;dump($cloner-&gt;cloneVar($var));
        };
    }

    private static function getDefaultContextProviders(): array
    {
        $contextProviders = [];

        if (!\in_array(\PHP_SAPI, ['cli', 'phpdbg'], true) &amp;&amp; class_exists(Request::class)) {
            $requestStack = new RequestStack();
            $requestStack-&gt;push(Request::createFromGlobals());
            $contextProviders['request'] = new RequestContextProvider($requestStack);
        }

        $fileLinkFormatter = class_exists(FileLinkFormatter::class) ? new FileLinkFormatter(null, $requestStack ?? null) : null;

        return $contextProviders + [
            'cli' =&gt; new CliContextProvider(),
            'source' =&gt; new SourceContextProvider(null, null, $fileLinkFormatter),
        ];
    }
}
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