Symfony\Component\VarDumper\Caster\ExceptionCaster::extractSource PHP Метод

    private static function extractSource($srcLines, $line, $srcContext, $title, $lang, $file = null)
    {
        $srcLines = explode("\n", $srcLines);
        $src = array();
        for ($i = $line - 1 - $srcContext; $i <= $line - 1 + $srcContext; ++$i) {
            $src[] = (isset($srcLines[$i]) ? $srcLines[$i] : '') . "\n";
        }
        $srcLines = array();
        $ltrim = 0;
        do {
            $pad = null;
            for ($i = $srcContext << 1; $i >= 0; --$i) {
                if (isset($src[$i][$ltrim]) && "\r" !== ($c = $src[$i][$ltrim]) && "\n" !== $c) {
                    if (null === $pad) {
                        $pad = $c;
                    }
                    if (' ' !== $c && "\t" !== $c || $pad !== $c) {
                        break;
                    }
                }
            }
            ++$ltrim;
        } while (0 > $i && null !== $pad);
        --$ltrim;
        foreach ($src as $i => $c) {
            if ($ltrim) {
                $c = isset($c[$ltrim]) && "\r" !== $c[$ltrim] ? substr($c, $ltrim) : ltrim($c, " \t");
            }
            $c = substr($c, 0, -1);
            if ($i !== $srcContext) {
                $c = new ConstStub('default', $c);
            } else {
                $c = new ConstStub($c, $title);
                if (null !== $file) {
                    $c->attr['file'] = $file;
                    $c->attr['line'] = $line;
                }
            }
            $c->attr['lang'] = $lang;
            $srcLines[sprintf("~%d", $i + $line - $srcContext)] = $c;
        }
        return new EnumStub($srcLines);
    }