DevelGeneratePluginManager.php

<?php

namespace Drupal\devel_generate;

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

/**
 * Plugin type manager for DevelGenerate plugins.
 */
class DevelGeneratePluginManager extends DefaultPluginManager {
    
    /**
     * Constructs a DevelGeneratePluginManager object.
     *
     * @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/DevelGenerate', $namespaces, $module_handler, NULL, 'Drupal\\devel_generate\\Annotation\\DevelGenerate');
        $this->alterInfo('devel_generate_info');
        $this->setCacheBackend($cache_backend, 'devel_generate_plugins');
    }
    
    /**
     * {@inheritdoc}
     */
    protected function findDefinitions() {
        $definitions = [];
        foreach (parent::findDefinitions() as $plugin_id => $plugin_definition) {
            $plugin_available = TRUE;
            foreach ($plugin_definition['dependencies'] as $module_name) {
                // If a plugin defines module dependencies and at least one module is
                // not installed don't make this plugin available.
                if (!$this->moduleHandler
                    ->moduleExists($module_name)) {
                    $plugin_available = FALSE;
                    break;
                }
            }
            if ($plugin_available) {
                $definitions[$plugin_id] = $plugin_definition;
            }
        }
        return $definitions;
    }

}