trait ViewsBulkOperationsActionCompletedTrait in Views Bulk Operations (VBO) 8.3

trait ViewsBulkOperationsActionCompletedTrait {

  /**
   * Set message function wrapper.
   *
   * @see \Drupal\Core\Messenger\MessengerInterface
   */
  public static function message($message = NULL, $type = 'status', $repeat = TRUE) {
    \Drupal::messenger()
      ->addMessage($message, $type, $repeat);
  }

  /**
   * Translation function wrapper.
   *
   * @see \Drupal\Core\StringTranslation\TranslationInterface:translate()
   */
  public static function translate($string, array $args = [], array $options = []) {
    return \Drupal::translation()
      ->translate($string, $args, $options);
  }

  /**
   * Batch finished callback.
   *
   * @param bool $success
   *   Was the process successful?
   * @param array $results
   *   Batch process results array.
   * @param array $operations
   *   Performed operations array.
   */
  public static function finished($success, array $results, array $operations) : ?RedirectResponse {
    if ($success) {
      $operations = array_count_values($results['operations']);
      $details = [];
      foreach ($operations as $op => $count) {
        $details[] = $op . ' (' . $count . ')';
      }
      $message = static::translate('Action processing results: @operations.', [
        '@operations' => implode(', ', $details),
      ]);
      static::message($message);
      if (isset($results['redirect_url'])) {
        @trigger_error('Passing the redirect_url value to results is deprecated in views_bulk_operations:8.x-3.14 and will be removed before views_bulk_operations:4.0. To redirect when processing is finished, override this method in your VBO action plugin class.', E_USER_DEPRECATED);
        return new RedirectResponse($results['redirect_url']
          ->setAbsolute()
          ->toString());
      }
    }
    else {
      $message = static::translate('Finished with an error.');
      static::message($message, 'error');
    }
    return NULL;
  }

}