NoType.php

<?php

namespace Drupal\action_test\Plugin\Action;

use Drupal\Core\Access\AccessResult;
use Drupal\Core\Action\ActionBase;
use Drupal\Core\Session\AccountInterface;

/**
 * Provides an operation with no type specified.
 *
 * @Action(
 *   id = "action_test_no_type",
 *   label = @Translation("An operation with no type specified")
 * )
 */
class NoType extends ActionBase {
  
  /**
   * {@inheritdoc}
   */
  public function execute($entity = NULL) {
  }
  
  /**
   * {@inheritdoc}
   */
  public function access($object, AccountInterface $account = NULL, $return_as_object = FALSE) {
    $result = AccessResult::allowed();
    return $return_as_object ? $result : $result->isAllowed();
  }

}