TokenStream.php in Zircon Profile 8.0

Namespace

Symfony\Component\CssSelector\Parser

File

vendor/symfony/css-selector/Parser/TokenStream.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\CssSelector\Parser;

use Symfony\Component\CssSelector\Exception\InternalErrorException;
use Symfony\Component\CssSelector\Exception\SyntaxErrorException;

/**
 * CSS selector token stream.
 *
 * This component is a port of the Python cssselect library,
 * which is copyright Ian Bicking, @see https://github.com/SimonSapin/cssselect.
 *
 * @author Jean-François Simon <[e-mail]>
 */
class TokenStream {

  /**
   * @var Token[]
   */
  private $tokens = array();

  /**
   * @var bool
   */
  private $frozen = false;

  /**
   * @var Token[]
   */
  private $used = array();

  /**
   * @var int
   */
  private $cursor = 0;

  /**
   * @var Token|null
   */
  private $peeked = null;

  /**
   * @var bool
   */
  private $peeking = false;

  /**
   * Pushes a token.
   *
   * @param Token $token
   *
   * @return TokenStream
   */
  public function push(Token $token) {
    $this->tokens[] = $token;
    return $this;
  }

  /**
   * Freezes stream.
   *
   * @return TokenStream
   */
  public function freeze() {
    $this->frozen = true;
    return $this;
  }

  /**
   * Returns next token.
   *
   * @throws InternalErrorException If there is no more token
   *
   * @return Token
   */
  public function getNext() {
    if ($this->peeking) {
      $this->peeking = false;
      $this->used[] = $this->peeked;
      return $this->peeked;
    }
    if (!isset($this->tokens[$this->cursor])) {
      throw new InternalErrorException('Unexpected token stream end.');
    }
    return $this->tokens[$this->cursor++];
  }

  /**
   * Returns peeked token.
   *
   * @return Token
   */
  public function getPeek() {
    if (!$this->peeking) {
      $this->peeked = $this
        ->getNext();
      $this->peeking = true;
    }
    return $this->peeked;
  }

  /**
   * Returns used tokens.
   *
   * @return Token[]
   */
  public function getUsed() {
    return $this->used;
  }

  /**
   * Returns nex identifier token.
   *
   * @throws SyntaxErrorException If next token is not an identifier
   *
   * @return string The identifier token value
   */
  public function getNextIdentifier() {
    $next = $this
      ->getNext();
    if (!$next
      ->isIdentifier()) {
      throw SyntaxErrorException::unexpectedToken('identifier', $next);
    }
    return $next
      ->getValue();
  }

  /**
   * Returns nex identifier or star delimiter token.
   *
   * @throws SyntaxErrorException If next token is not an identifier or a star delimiter
   *
   * @return null|string The identifier token value or null if star found
   */
  public function getNextIdentifierOrStar() {
    $next = $this
      ->getNext();
    if ($next
      ->isIdentifier()) {
      return $next
        ->getValue();
    }
    if ($next
      ->isDelimiter(array(
      '*',
    ))) {
      return;
    }
    throw SyntaxErrorException::unexpectedToken('identifier or "*"', $next);
  }

  /**
   * Skips next whitespace if any.
   */
  public function skipWhitespace() {
    $peek = $this
      ->getPeek();
    if ($peek
      ->isWhitespace()) {
      $this
        ->getNext();
    }
  }

}

Classes

Name	Description
TokenStream	CSS selector token stream.