_test/vendor/symfony/css-selector/Parser/TokenStream.php

   1 <?php
   2
   3 /*
   4  * This file is part of the Symfony package.
   5  *
   6  * (c) Fabien Potencier <fabien@symfony.com>
   7  *
   8  * For the full copyright and license information, please view the LICENSE
   9  * file that was distributed with this source code.
  10  */
  11
  12 namespace Symfony\Component\CssSelector\Parser;
  13
  14 use Symfony\Component\CssSelector\Exception\InternalErrorException;
  15 use Symfony\Component\CssSelector\Exception\SyntaxErrorException;
  16
  17 /**
  18  * CSS selector token stream.
  19  *
  20  * This component is a port of the Python cssselect library,
  21  * which is copyright Ian Bicking, @see https://github.com/SimonSapin/cssselect.
  22  *
  23  * @author Jean-François Simon <jeanfrancois.simon@sensiolabs.com>
  24  *
  25  * @internal
  26  */
  27 class TokenStream
  28 {
  29     /**
  30      * @var Token[]
  31      */
  32     private $tokens = [];
  33
  34     /**
  35      * @var Token[]
  36      */
  37     private $used = [];
  38
  39     /**
  40      * @var int
  41      */
  42     private $cursor = 0;
  43
  44     /**
  45      * @var Token|null
  46      */
  47     private $peeked;
  48
  49     /**
  50      * @var bool
  51      */
  52     private $peeking = false;
  53
  54     /**
  55      * Pushes a token.
  56      *
  57      * @return $this
  58      */
  59     public function push(Token $token): self
  60     {
  61         $this->tokens[] = $token;
  62
  63         return $this;
  64     }
  65
  66     /**
  67      * Freezes stream.
  68      *
  69      * @return $this
  70      */
  71     public function freeze(): self
  72     {
  73         return $this;
  74     }
  75
  76     /**
  77      * Returns next token.
  78      *
  79      * @throws InternalErrorException If there is no more token
  80      */
  81     public function getNext(): Token
  82     {
  83         if ($this->peeking) {
  84             $this->peeking = false;
  85             $this->used[] = $this->peeked;
  86
  87             return $this->peeked;
  88         }
  89
  90         if (!isset($this->tokens[$this->cursor])) {
  91             throw new InternalErrorException('Unexpected token stream end.');
  92         }
  93
  94         return $this->tokens[$this->cursor++];
  95     }
  96
  97     /**
  98      * Returns peeked token.
  99      */
 100     public function getPeek(): Token
 101     {
 102         if (!$this->peeking) {
 103             $this->peeked = $this->getNext();
 104             $this->peeking = true;
 105         }
 106
 107         return $this->peeked;
 108     }
 109
 110     /**
 111      * Returns used tokens.
 112      *
 113      * @return Token[]
 114      */
 115     public function getUsed(): array
 116     {
 117         return $this->used;
 118     }
 119
 120     /**
 121      * Returns nex identifier token.
 122      *
 123      * @return string The identifier token value
 124      *
 125      * @throws SyntaxErrorException If next token is not an identifier
 126      */
 127     public function getNextIdentifier(): string
 128     {
 129         $next = $this->getNext();
 130
 131         if (!$next->isIdentifier()) {
 132             throw SyntaxErrorException::unexpectedToken('identifier', $next);
 133         }
 134
 135         return $next->getValue();
 136     }
 137
 138     /**
 139      * Returns nex identifier or star delimiter token.
 140      *
 141      * @return string|null The identifier token value or null if star found
 142      *
 143      * @throws SyntaxErrorException If next token is not an identifier or a star delimiter
 144      */
 145     public function getNextIdentifierOrStar(): ?string
 146     {
 147         $next = $this->getNext();
 148
 149         if ($next->isIdentifier()) {
 150             return $next->getValue();
 151         }
 152
 153         if ($next->isDelimiter(['*'])) {
 154             return null;
 155         }
 156
 157         throw SyntaxErrorException::unexpectedToken('identifier or "*"', $next);
 158     }
 159
 160     /**
 161      * Skips next whitespace if any.
 162      */
 163     public function skipWhitespace()
 164     {
 165         $peek = $this->getPeek();
 166
 167         if ($peek->isWhitespace()) {
 168             $this->getNext();
 169         }
 170     }
 171 }