TwigTransTokenParser.php in Drupal 9

Namespace

Drupal\Core\Template

File

core/lib/Drupal/Core/Template/TwigTransTokenParser.php

<?php

namespace Drupal\Core\Template;

use Twig\Error\SyntaxError;
use Twig\Node\Expression\FilterExpression;
use Twig\Node\Expression\GetAttrExpression;
use Twig\Node\Expression\NameExpression;
use Twig\Node\Node;
use Twig\Node\PrintNode;
use Twig\Node\TextNode;
use Twig\Token;
use Twig\TokenParser\AbstractTokenParser;

/**
 * A class that defines the Twig 'trans' token parser for Drupal.
 *
 * The token parser converts a token stream created from template source
 * code into an Abstract Syntax Tree (AST).  The AST will later be compiled
 * into PHP code usable for runtime execution of the template.
 *
 * @see https://twig-extensions.readthedocs.io/en/latest/i18n.html
 * @see https://github.com/fabpot/Twig-extensions
 */
class TwigTransTokenParser extends AbstractTokenParser {

  /**
   * {@inheritdoc}
   */
  public function parse(Token $token) {
    $lineno = $token
      ->getLine();
    $stream = $this->parser
      ->getStream();
    $body = NULL;
    $options = NULL;
    $count = NULL;
    $plural = NULL;
    if (!$stream
      ->test(Token::BLOCK_END_TYPE) && $stream
      ->test(Token::STRING_TYPE)) {
      $body = $this->parser
        ->getExpressionParser()
        ->parseExpression();
    }
    if (!$stream
      ->test(Token::BLOCK_END_TYPE) && $stream
      ->test(Token::NAME_TYPE, 'with')) {
      $stream
        ->next();
      $options = $this->parser
        ->getExpressionParser()
        ->parseExpression();
    }
    if (!$body) {
      $stream
        ->expect(Token::BLOCK_END_TYPE);
      $body = $this->parser
        ->subparse([
        $this,
        'decideForFork',
      ]);
      if ('plural' === $stream
        ->next()
        ->getValue()) {
        $count = $this->parser
          ->getExpressionParser()
          ->parseExpression();
        $stream
          ->expect(Token::BLOCK_END_TYPE);
        $plural = $this->parser
          ->subparse([
          $this,
          'decideForEnd',
        ], TRUE);
      }
    }
    $stream
      ->expect(Token::BLOCK_END_TYPE);
    $this
      ->checkTransString($body, $lineno);
    $node = new TwigNodeTrans($body, $plural, $count, $options, $lineno, $this
      ->getTag());
    return $node;
  }

  /**
   * Detect a 'plural' switch or the end of a 'trans' tag.
   */
  public function decideForFork($token) {
    return $token
      ->test([
      'plural',
      'endtrans',
    ]);
  }

  /**
   * Detect the end of a 'trans' tag.
   */
  public function decideForEnd($token) {
    return $token
      ->test('endtrans');
  }

  /**
   * {@inheritdoc}
   */
  public function getTag() {
    return 'trans';
  }

  /**
   * Ensure that any nodes that are parsed are only of allowed types.
   *
   * @param \Twig\Node\Node $body
   *   The expression to check.
   * @param int $lineno
   *   The source line.
   *
   * @throws \Twig\Error\SyntaxError
   */
  protected function checkTransString(Node $body, $lineno) {
    foreach ($body as $node) {
      if ($node instanceof TextNode || $node instanceof PrintNode && $node
        ->getNode('expr') instanceof NameExpression || $node instanceof PrintNode && $node
        ->getNode('expr') instanceof GetAttrExpression || $node instanceof PrintNode && $node
        ->getNode('expr') instanceof FilterExpression) {
        continue;
      }
      throw new SyntaxError(sprintf('The text to be translated with "trans" can only contain references to simple variables'), $lineno);
    }
  }

}

Classes

Name	Description
TwigTransTokenParser	A class that defines the Twig 'trans' token parser for Drupal.