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    <h3>Editing: SourceContextProvider.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\Dumper\ContextProvider;

use Symfony\Component\HttpKernel\Debug\FileLinkFormatter;
use Symfony\Component\VarDumper\Cloner\VarCloner;
use Symfony\Component\VarDumper\Dumper\HtmlDumper;
use Symfony\Component\VarDumper\VarDumper;
use Twig\Template;

/**
 * Tries to provide context from sources (class name, file, line, code excerpt, ...).
 *
 * @author Nicolas Grekas &lt;p@tchwork.com&gt;
 * @author Maxime Steinhausser &lt;maxime.steinhausser@gmail.com&gt;
 */
final class SourceContextProvider implements ContextProviderInterface
{
    private $limit;
    private $charset;
    private $projectDir;
    private $fileLinkFormatter;

    public function __construct(?string $charset = null, ?string $projectDir = null, ?FileLinkFormatter $fileLinkFormatter = null, int $limit = 9)
    {
        $this-&gt;charset = $charset;
        $this-&gt;projectDir = $projectDir;
        $this-&gt;fileLinkFormatter = $fileLinkFormatter;
        $this-&gt;limit = $limit;
    }

    public function getContext(): ?array
    {
        $trace = debug_backtrace(\DEBUG_BACKTRACE_PROVIDE_OBJECT | \DEBUG_BACKTRACE_IGNORE_ARGS, $this-&gt;limit);

        $file = $trace[1]['file'];
        $line = $trace[1]['line'];
        $name = '-' === $file || 'Standard input code' === $file ? 'Standard input code' : false;
        $fileExcerpt = false;

        for ($i = 2; $i &lt; $this-&gt;limit; ++$i) {
            if (isset($trace[$i]['class'], $trace[$i]['function'])
                &amp;&amp; 'dump' === $trace[$i]['function']
                &amp;&amp; VarDumper::class === $trace[$i]['class']
            ) {
                $file = $trace[$i]['file'] ?? $file;
                $line = $trace[$i]['line'] ?? $line;

                while (++$i &lt; $this-&gt;limit) {
                    if (isset($trace[$i]['function'], $trace[$i]['file']) &amp;&amp; empty($trace[$i]['class']) &amp;&amp; !str_starts_with($trace[$i]['function'], 'call_user_func')) {
                        $file = $trace[$i]['file'];
                        $line = $trace[$i]['line'];

                        break;
                    } elseif (isset($trace[$i]['object']) &amp;&amp; $trace[$i]['object'] instanceof Template) {
                        $template = $trace[$i]['object'];
                        $name = $template-&gt;getTemplateName();
                        $src = method_exists($template, 'getSourceContext') ? $template-&gt;getSourceContext()-&gt;getCode() : (method_exists($template, 'getSource') ? $template-&gt;getSource() : false);
                        $info = $template-&gt;getDebugInfo();
                        if (isset($info[$trace[$i - 1]['line']])) {
                            $line = $info[$trace[$i - 1]['line']];
                            $file = method_exists($template, 'getSourceContext') ? $template-&gt;getSourceContext()-&gt;getPath() : null;

                            if ($src) {
                                $src = explode(&quot;\n&quot;, $src);
                                $fileExcerpt = [];

                                for ($i = max($line - 3, 1), $max = min($line + 3, \count($src)); $i &lt;= $max; ++$i) {
                                    $fileExcerpt[] = '&lt;li'.($i === $line ? ' class=&quot;selected&quot;' : '').'&gt;&lt;code&gt;'.$this-&gt;htmlEncode($src[$i - 1]).'&lt;/code&gt;&lt;/li&gt;';
                                }

                                $fileExcerpt = '&lt;ol start=&quot;'.max($line - 3, 1).'&quot;&gt;'.implode(&quot;\n&quot;, $fileExcerpt).'&lt;/ol&gt;';
                            }
                        }
                        break;
                    }
                }
                break;
            }
        }

        if (false === $name) {
            $name = str_replace('\\', '/', $file);
            $name = substr($name, strrpos($name, '/') + 1);
        }

        $context = ['name' =&gt; $name, 'file' =&gt; $file, 'line' =&gt; $line];
        $context['file_excerpt'] = $fileExcerpt;

        if (null !== $this-&gt;projectDir) {
            $context['project_dir'] = $this-&gt;projectDir;
            if (str_starts_with($file, $this-&gt;projectDir)) {
                $context['file_relative'] = ltrim(substr($file, \strlen($this-&gt;projectDir)), \DIRECTORY_SEPARATOR);
            }
        }

        if ($this-&gt;fileLinkFormatter &amp;&amp; $fileLink = $this-&gt;fileLinkFormatter-&gt;format($context['file'], $context['line'])) {
            $context['file_link'] = $fileLink;
        }

        return $context;
    }

    private function htmlEncode(string $s): string
    {
        $html = '';

        $dumper = new HtmlDumper(function ($line) use (&amp;$html) { $html .= $line; }, $this-&gt;charset);
        $dumper-&gt;setDumpHeader('');
        $dumper-&gt;setDumpBoundaries('', '');

        $cloner = new VarCloner();
        $dumper-&gt;dump($cloner-&gt;cloneVar($s));

        return substr(strip_tags($html), 1, -1);
    }
}
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