Chris@0: <?php
Chris@0: 
Chris@0: /*
Chris@0:  * This file is part of Psy Shell.
Chris@0:  *
Chris@0:  * (c) 2012-2018 Justin Hileman
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 Psy;
Chris@0: 
Chris@0: use PhpParser\Lexer;
Chris@0: use PhpParser\Parser;
Chris@0: use PhpParser\ParserFactory as OriginalParserFactory;
Chris@0: 
Chris@0: /**
Chris@0:  * Parser factory to abstract over PHP parser library versions.
Chris@0:  */
Chris@0: class ParserFactory
Chris@0: {
Chris@0:     const ONLY_PHP5   = 'ONLY_PHP5';
Chris@0:     const ONLY_PHP7   = 'ONLY_PHP7';
Chris@0:     const PREFER_PHP5 = 'PREFER_PHP5';
Chris@0:     const PREFER_PHP7 = 'PREFER_PHP7';
Chris@0: 
Chris@0:     /**
Chris@0:      * Possible kinds of parsers for the factory, from PHP parser library.
Chris@0:      *
Chris@0:      * @return array
Chris@0:      */
Chris@0:     public static function getPossibleKinds()
Chris@0:     {
Chris@0:         return ['ONLY_PHP5', 'ONLY_PHP7', 'PREFER_PHP5', 'PREFER_PHP7'];
Chris@0:     }
Chris@0: 
Chris@0:     /**
Chris@0:      * Is this parser factory supports kinds?
Chris@0:      *
Chris@0:      * PHP parser < 2.0 doesn't support kinds, >= 2.0 — does.
Chris@0:      *
Chris@0:      * @return bool
Chris@0:      */
Chris@0:     public function hasKindsSupport()
Chris@0:     {
Chris@4:         return \class_exists('PhpParser\ParserFactory');
Chris@0:     }
Chris@0: 
Chris@0:     /**
Chris@0:      * Default kind (if supported, based on current interpreter's version).
Chris@0:      *
Chris@0:      * @return string|null
Chris@0:      */
Chris@0:     public function getDefaultKind()
Chris@0:     {
Chris@0:         if ($this->hasKindsSupport()) {
Chris@4:             return \version_compare(PHP_VERSION, '7.0', '>=') ? static::ONLY_PHP7 : static::ONLY_PHP5;
Chris@0:         }
Chris@0:     }
Chris@0: 
Chris@0:     /**
Chris@0:      * New parser instance with given kind.
Chris@0:      *
Chris@0:      * @param string|null $kind One of class constants (only for PHP parser 2.0 and above)
Chris@0:      *
Chris@0:      * @return Parser
Chris@0:      */
Chris@0:     public function createParser($kind = null)
Chris@0:     {
Chris@0:         if ($this->hasKindsSupport()) {
Chris@0:             $originalFactory = new OriginalParserFactory();
Chris@0: 
Chris@0:             $kind = $kind ?: $this->getDefaultKind();
Chris@0: 
Chris@4:             if (!\in_array($kind, static::getPossibleKinds())) {
Chris@0:                 throw new \InvalidArgumentException('Unknown parser kind');
Chris@0:             }
Chris@0: 
Chris@4:             $parser = $originalFactory->create(\constant('PhpParser\ParserFactory::' . $kind));
Chris@0:         } else {
Chris@0:             if ($kind !== null) {
Chris@0:                 throw new \InvalidArgumentException('Install PHP Parser v2.x to specify parser kind');
Chris@0:             }
Chris@0: 
Chris@0:             $parser = new Parser(new Lexer());
Chris@0:         }
Chris@0: 
Chris@0:         return $parser;
Chris@0:     }
Chris@0: }