Yosymfony\Spress\Core\Plugin\PluginManager::callInitialize PHP Method

    public function callInitialize()
    {
        foreach ($this->pluginCollection as $plugin) {
            $subscriber = new EventSubscriber();
            $plugin->initialize($subscriber);
            $this->eventSubscriberPlugins[] = [$plugin, $subscriber];
            $this->addListeners($plugin, $subscriber);
        }
    }

 public function testCallInitialize()
 {
     $pm = new PluginManager(new EventDispatcher());
     $plugin1 = $this->getMockBuilder('\\Yosymfony\\Spress\\Core\\Plugin\\PluginInterface')->getMock();
     $plugin2 = $this->getMockBuilder('\\Yosymfony\\Spress\\Core\\Plugin\\PluginInterface')->getMock();
     $plugin1->expects($this->once())->method('initialize');
     $plugin2->expects($this->once())->method('initialize');
     $pluginCollection = $pm->getPluginCollection();
     $pluginCollection->add('plugin1', $plugin1);
     $pluginCollection->add('plugin2', $plugin2);
     $pm->callInitialize();
 }