Chris@0: <?php
Chris@0: 
Chris@0: /*
Chris@0:  * This file is part of the Symfony package.
Chris@0:  *
Chris@0:  * (c) Fabien Potencier <fabien@symfony.com>
Chris@0:  *
Chris@0:  * For the full copyright and license information, please view the LICENSE
Chris@0:  * file that was distributed with this source code.
Chris@0:  */
Chris@0: 
Chris@0: namespace Symfony\Component\Yaml;
Chris@0: 
Chris@0: /**
Chris@0:  * Escaper encapsulates escaping rules for single and double-quoted
Chris@0:  * YAML strings.
Chris@0:  *
Chris@0:  * @author Matthew Lewinski <matthew@lewinski.org>
Chris@0:  *
Chris@0:  * @internal
Chris@0:  */
Chris@0: class Escaper
Chris@0: {
Chris@0:     // Characters that would cause a dumped string to require double quoting.
Chris@0:     const REGEX_CHARACTER_TO_ESCAPE = "[\\x00-\\x1f]|\xc2\x85|\xc2\xa0|\xe2\x80\xa8|\xe2\x80\xa9";
Chris@0: 
Chris@0:     // Mapping arrays for escaping a double quoted string. The backslash is
Chris@0:     // first to ensure proper escaping because str_replace operates iteratively
Chris@0:     // on the input arrays. This ordering of the characters avoids the use of strtr,
Chris@0:     // which performs more slowly.
Chris@17:     private static $escapees = ['\\', '\\\\', '\\"', '"',
Chris@0:                                      "\x00",  "\x01",  "\x02",  "\x03",  "\x04",  "\x05",  "\x06",  "\x07",
Chris@0:                                      "\x08",  "\x09",  "\x0a",  "\x0b",  "\x0c",  "\x0d",  "\x0e",  "\x0f",
Chris@0:                                      "\x10",  "\x11",  "\x12",  "\x13",  "\x14",  "\x15",  "\x16",  "\x17",
Chris@0:                                      "\x18",  "\x19",  "\x1a",  "\x1b",  "\x1c",  "\x1d",  "\x1e",  "\x1f",
Chris@0:                                      "\xc2\x85", "\xc2\xa0", "\xe2\x80\xa8", "\xe2\x80\xa9",
Chris@17:                                ];
Chris@17:     private static $escaped = ['\\\\', '\\"', '\\\\', '\\"',
Chris@0:                                      '\\0',   '\\x01', '\\x02', '\\x03', '\\x04', '\\x05', '\\x06', '\\a',
Chris@0:                                      '\\b',   '\\t',   '\\n',   '\\v',   '\\f',   '\\r',   '\\x0e', '\\x0f',
Chris@0:                                      '\\x10', '\\x11', '\\x12', '\\x13', '\\x14', '\\x15', '\\x16', '\\x17',
Chris@0:                                      '\\x18', '\\x19', '\\x1a', '\\e',   '\\x1c', '\\x1d', '\\x1e', '\\x1f',
Chris@0:                                      '\\N', '\\_', '\\L', '\\P',
Chris@17:                               ];
Chris@0: 
Chris@0:     /**
Chris@0:      * Determines if a PHP value would require double quoting in YAML.
Chris@0:      *
Chris@0:      * @param string $value A PHP value
Chris@0:      *
Chris@0:      * @return bool True if the value would require double quotes
Chris@0:      */
Chris@0:     public static function requiresDoubleQuoting($value)
Chris@0:     {
Chris@0:         return 0 < preg_match('/'.self::REGEX_CHARACTER_TO_ESCAPE.'/u', $value);
Chris@0:     }
Chris@0: 
Chris@0:     /**
Chris@0:      * Escapes and surrounds a PHP value with double quotes.
Chris@0:      *
Chris@0:      * @param string $value A PHP value
Chris@0:      *
Chris@0:      * @return string The quoted, escaped string
Chris@0:      */
Chris@0:     public static function escapeWithDoubleQuotes($value)
Chris@0:     {
Chris@0:         return sprintf('"%s"', str_replace(self::$escapees, self::$escaped, $value));
Chris@0:     }
Chris@0: 
Chris@0:     /**
Chris@0:      * Determines if a PHP value would require single quoting in YAML.
Chris@0:      *
Chris@0:      * @param string $value A PHP value
Chris@0:      *
Chris@0:      * @return bool True if the value would require single quotes
Chris@0:      */
Chris@0:     public static function requiresSingleQuoting($value)
Chris@0:     {
Chris@0:         // Determines if a PHP value is entirely composed of a value that would
Chris@0:         // require single quoting in YAML.
Chris@17:         if (\in_array(strtolower($value), ['null', '~', 'true', 'false', 'y', 'n', 'yes', 'no', 'on', 'off'])) {
Chris@0:             return true;
Chris@0:         }
Chris@0: 
Chris@0:         // Determines if the PHP value contains any single characters that would
Chris@0:         // cause it to require single quoting in YAML.
Chris@0:         return 0 < preg_match('/[ \s \' " \: \{ \} \[ \] , & \* \# \?] | \A[ \- ? | < > = ! % @ ` ]/x', $value);
Chris@0:     }
Chris@0: 
Chris@0:     /**
Chris@0:      * Escapes and surrounds a PHP value with single quotes.
Chris@0:      *
Chris@0:      * @param string $value A PHP value
Chris@0:      *
Chris@0:      * @return string The quoted, escaped string
Chris@0:      */
Chris@0:     public static function escapeWithSingleQuotes($value)
Chris@0:     {
Chris@0:         return sprintf("'%s'", str_replace('\'', '\'\'', $value));
Chris@0:     }
Chris@0: }