code: public function actionReport($sourcePath, $translationPath, $title = 'Translation report')
      {
          $sourcePath = trim($sourcePath, '/\\');
          $translationPath = trim($translationPath, '/\\');
  
          $results = [];
  
          $dir = new DirectoryIterator($sourcePath);
          foreach ($dir as $fileinfo) {
              /* @var $fileinfo DirectoryIterator */
              if (!$fileinfo->isDot() && !$fileinfo->isDir()) {
                  $translatedFilePath = $translationPath . '/' . $fileinfo->getFilename();
                  $sourceFilePath = $sourcePath . '/' . $fileinfo->getFilename();
  
                  $errors = $this->checkFiles($translatedFilePath);
                  $diff = empty($errors) ? $this->getDiff($translatedFilePath, $sourceFilePath) : '';
                  if (!empty($diff)) {
                      $errors[] = 'Translation outdated.';
                  }
  
                  $result = [
                      'errors' => $errors,
                      'diff' => $diff,
                  ];
  
                  $results[$fileinfo->getFilename()] = $result;
              }
          }
  
          // checking if there are obsolete translation files
          $dir = new DirectoryIterator($translationPath);
          foreach ($dir as $fileinfo) {
              /* @var $fileinfo \DirectoryIterator */
              if (!$fileinfo->isDot() && !$fileinfo->isDir()) {
                  $translatedFilePath = $translationPath . '/' . $fileinfo->getFilename();
  
                  $errors = $this->checkFiles(null, $translatedFilePath);
                  if (!empty($errors)) {
                      $results[$fileinfo->getFilename()]['errors'] = $errors;
                  }
              }
          }
  
          echo $this->renderFile(__DIR__ . '/views/translation/report_html.php', [
              'results' => $results,
              'sourcePath' => $sourcePath,
              'translationPath' => $translationPath,
              'title' => $title,
          ]);
      }
docs: Creates a report about documentation updates since last update of same named translations.
  
  @param string $sourcePath the directory where the original documentation files are
  @param string $translationPath the directory where the translated documentation files are
  @param string $title custom title to use for report
  @return string