code: private function findParenthesisEnd(Tokens $tokens, $structureTokenIndex)
      {
          $nextIndex = $tokens->getNextMeaningfulToken($structureTokenIndex);
          $nextToken = $tokens[$nextIndex];
  
          // return if next token is not opening parenthesis
          if (!$nextToken->equals('(')) {
              return $structureTokenIndex;
          }
  
          return $tokens->findBlockEnd(Tokens::BLOCK_TYPE_PARENTHESIS_BRACE, $nextIndex);
      }
docs: @param Tokens $tokens
  @param int    $structureTokenIndex
  
  @return int