inc/Twig/TokenParser/If.php

   1 <?php
   2
   3 /*
   4  * This file is part of Twig.
   5  *
   6  * (c) 2009 Fabien Potencier
   7  * (c) 2009 Armin Ronacher
   8  *
   9  * For the full copyright and license information, please view the LICENSE
  10  * file that was distributed with this source code.
  11  */
  12
  13 /**
  14  * Tests a condition.
  15  *
  16  * <pre>
  17  * {% if users %}
  18  *  <ul>
  19  *    {% for user in users %}
  20  *      <li>{{ user.username|e }}</li>
  21  *    {% endfor %}
  22  *  </ul>
  23  * {% endif %}
  24  * </pre>
  25  */
  26 class Twig_TokenParser_If extends Twig_TokenParser
  27 {
  28     /**
  29      * Parses a token and returns a node.
  30      *
  31      * @param Twig_Token $token A Twig_Token instance
  32      *
  33      * @return Twig_NodeInterface A Twig_NodeInterface instance
  34      */
  35     public function parse(Twig_Token $token)
  36     {
  37         $lineno = $token->getLine();
  38         $expr = $this->parser->getExpressionParser()->parseExpression();
  39         $stream = $this->parser->getStream();
  40         $stream->expect(Twig_Token::BLOCK_END_TYPE);
  41         $body = $this->parser->subparse(array($this, 'decideIfFork'));
  42         $tests = array($expr, $body);
  43         $else = null;
  44
  45         $end = false;
  46         while (!$end) {
  47             switch ($stream->next()->getValue()) {
  48                 case 'else':
  49                     $stream->expect(Twig_Token::BLOCK_END_TYPE);
  50                     $else = $this->parser->subparse(array($this, 'decideIfEnd'));
  51                     break;
  52
  53                 case 'elseif':
  54                     $expr = $this->parser->getExpressionParser()->parseExpression();
  55                     $stream->expect(Twig_Token::BLOCK_END_TYPE);
  56                     $body = $this->parser->subparse(array($this, 'decideIfFork'));
  57                     $tests[] = $expr;
  58                     $tests[] = $body;
  59                     break;
  60
  61                 case 'endif':
  62                     $end = true;
  63                     break;
  64
  65                 default:
  66                     throw new Twig_Error_Syntax(sprintf('Unexpected end of template. Twig was looking for the following tags "else", "elseif", or "endif" to close the "if" block started at line %d)', $lineno), $stream->getCurrent()->getLine(), $stream->getFilename());
  67             }
  68         }
  69
  70         $stream->expect(Twig_Token::BLOCK_END_TYPE);
  71
  72         return new Twig_Node_If(new Twig_Node($tests), $else, $lineno, $this->getTag());
  73     }
  74
  75     public function decideIfFork(Twig_Token $token)
  76     {
  77         return $token->test(array('elseif', 'else', 'endif'));
  78     }
  79
  80     public function decideIfEnd(Twig_Token $token)
  81     {
  82         return $token->test(array('endif'));
  83     }
  84
  85     /**
  86      * Gets the tag name associated with this token parser.
  87      *
  88      * @return string The tag name
  89      */
  90     public function getTag()
  91     {
  92         return 'if';
  93     }
  94 }