Unescaper.php in Lockr 7.3

Namespace

Symfony\Component\Yaml

File

vendor/symfony/yaml/Unescaper.php

<?php

/*
 * This file is part of the Symfony package.
 *
 * (c) Fabien Potencier <[e-mail]>
 *
 * For the full copyright and license information, please view the LICENSE
 * file that was distributed with this source code.
 */
namespace Symfony\Component\Yaml;

use Symfony\Component\Yaml\Exception\ParseException;

/**
 * Unescaper encapsulates unescaping rules for single and double-quoted
 * YAML strings.
 *
 * @author Matthew Lewinski <[e-mail]>
 *
 * @internal
 */
class Unescaper {

  /**
   * Regex fragment that matches an escaped character in a double quoted string.
   */
  const REGEX_ESCAPED_CHARACTER = '\\\\(x[0-9a-fA-F]{2}|u[0-9a-fA-F]{4}|U[0-9a-fA-F]{8}|.)';

  /**
   * Unescapes a single quoted string.
   *
   * @param string $value A single quoted string
   *
   * @return string The unescaped string
   */
  public function unescapeSingleQuotedString($value) {
    return str_replace('\'\'', '\'', $value);
  }

  /**
   * Unescapes a double quoted string.
   *
   * @param string $value A double quoted string
   *
   * @return string The unescaped string
   */
  public function unescapeDoubleQuotedString($value) {
    $callback = function ($match) {
      return $this
        ->unescapeCharacter($match[0]);
    };

    // evaluate the string
    return preg_replace_callback('/' . self::REGEX_ESCAPED_CHARACTER . '/u', $callback, $value);
  }

  /**
   * Unescapes a character that was found in a double-quoted string.
   *
   * @param string $value An escaped character
   *
   * @return string The unescaped character
   */
  private function unescapeCharacter($value) {
    switch ($value[1]) {
      case '0':
        return "\0";
      case 'a':
        return "\7";
      case 'b':
        return "\10";
      case 't':
        return "\t";
      case "\t":
        return "\t";
      case 'n':
        return "\n";
      case 'v':
        return "\v";
      case 'f':
        return "\f";
      case 'r':
        return "\r";
      case 'e':
        return "\33";
      case ' ':
        return ' ';
      case '"':
        return '"';
      case '/':
        return '/';
      case '\\':
        return '\\';
      case 'N':

        // U+0085 NEXT LINE
        return "…";
      case '_':

        // U+00A0 NO-BREAK SPACE
        return " ";
      case 'L':

        // U+2028 LINE SEPARATOR
        return "
";
      case 'P':

        // U+2029 PARAGRAPH SEPARATOR
        return "
";
      case 'x':
        return self::utf8chr(hexdec(substr($value, 2, 2)));
      case 'u':
        return self::utf8chr(hexdec(substr($value, 2, 4)));
      case 'U':
        return self::utf8chr(hexdec(substr($value, 2, 8)));
      default:
        throw new ParseException(sprintf('Found unknown escape character "%s".', $value));
    }
  }

  /**
   * Get the UTF-8 character for the given code point.
   *
   * @param int $c The unicode code point
   *
   * @return string The corresponding UTF-8 character
   */
  private static function utf8chr($c) {
    if (0x80 > ($c %= 0x200000)) {
      return \chr($c);
    }
    if (0x800 > $c) {
      return \chr(0xc0 | $c >> 6) . \chr(0x80 | $c & 0x3f);
    }
    if (0x10000 > $c) {
      return \chr(0xe0 | $c >> 12) . \chr(0x80 | $c >> 6 & 0x3f) . \chr(0x80 | $c & 0x3f);
    }
    return \chr(0xf0 | $c >> 18) . \chr(0x80 | $c >> 12 & 0x3f) . \chr(0x80 | $c >> 6 & 0x3f) . \chr(0x80 | $c & 0x3f);
  }

}

Classes

Name	Description
Unescaper	Unescaper encapsulates unescaping rules for single and double-quoted YAML strings.