code: protected function applyFix(\SplFileInfo $file, Tokens $tokens)
      {
          $end = $tokens->count() - 1;
          $functionsAnalyzer = new FunctionsAnalyzer();
  
          foreach (self::$functions as $map) {
              // the sequence is the function name, followed by "(" and a quoted string
              $seq = [[T_STRING, $map[0]], '(', [T_CONSTANT_ENCAPSED_STRING]];
  
              $currIndex = 0;
              while (null !== $currIndex) {
                  $match = $tokens->findSequence($seq, $currIndex, $end, false);
  
                  // did we find a match?
                  if (null === $match) {
                      break;
                  }
  
                  // findSequence also returns the tokens, but we're only interested in the indexes, i.e.:
                  // 0 => function name,
                  // 1 => bracket "("
                  // 2 => quoted string passed as 1st parameter
                  $match = array_keys($match);
  
                  // advance tokenizer cursor
                  $currIndex = $match[2];
  
                  if (!$functionsAnalyzer->isGlobalFunctionCall($tokens, $match[0])) {
                      continue;
                  }
  
                  // ensure the first parameter is just a string (e.g. has nothing appended)
                  $next = $tokens->getNextMeaningfulToken($match[2]);
                  if (null === $next || !$tokens[$next]->equalsAny([',', ')'])) {
                      continue;
                  }
  
                  // convert to PCRE
                  $regexTokenContent = $tokens[$match[2]]->getContent();
                  $string = substr($regexTokenContent, 1, -1);
                  $quote = $regexTokenContent[0];
                  $delim = $this->getBestDelimiter($string);
                  $preg = $delim.addcslashes($string, $delim).$delim.'D'.$map[2];
  
                  // check if the preg is valid
                  if (!$this->checkPreg($preg)) {
                      continue;
                  }
  
                  // modify function and argument
                  $tokens[$match[0]] = new Token([T_STRING, $map[1]]);
                  $tokens[$match[2]] = new Token([T_CONSTANT_ENCAPSED_STRING, $quote.$preg.$quote]);
              }
          }
      }
docs: {@inheritdoc}