SearchPluginManager.php

<?php

namespace Drupal\search;

use Drupal\Core\Extension\ModuleHandlerInterface;
use Drupal\Core\Plugin\DefaultPluginManager;
use Drupal\Core\Cache\CacheBackendInterface;

/**
 * SearchExecute plugin manager.
 */
class SearchPluginManager extends DefaultPluginManager {
    
    /**
     * Constructs SearchPluginManager.
     *
     * @param \Traversable $namespaces
     *   An object that implements \Traversable which contains the root paths
     *   keyed by the corresponding namespace to look for plugin implementations.
     * @param \Drupal\Core\Cache\CacheBackendInterface $cache_backend
     *   Cache backend instance to use.
     * @param \Drupal\Core\Extension\ModuleHandlerInterface $module_handler
     *   The module handler to invoke the alter hook with.
     */
    public function __construct(\Traversable $namespaces, CacheBackendInterface $cache_backend, ModuleHandlerInterface $module_handler) {
        parent::__construct('Plugin/Search', $namespaces, $module_handler, 'Drupal\\search\\Plugin\\SearchInterface', 'Drupal\\search\\Annotation\\SearchPlugin');
        $this->setCacheBackend($cache_backend, 'search_plugins');
        $this->alterInfo('search_plugin');
    }

}