final-notification-subscriber.php

<?php

declare(strict_types=1);

namespace App\User\Notification;

use App\Notification\EmailNotificationInterface;
use App\Notification\NotificationManagerInterface;
use App\Events\PostRegistrationEvent;
use App\User\Notification\WelcomeGreetingEmailNotificationFactory;
use Symfony\Component\EventDispatcher\EventSubscriberInterface;

final class EmailNotification implements EventSubscriberInterface
{
    private NotificationManagerInterface $notificationManager;
    private WelcomeGreetingEmailNotificationFactory $notificationFactory;
    
    public function __construct(
        NotificationManagerInterface $notificationManager,
        WelcomeGreetingEmailNotificationFactory $notificationFactory
    ) {
        $this->notificationManager = $notificationManager;
        $this->notificationFactory = $notificationFactory;
    }

    /** {@inheritDoc} */
    public static function getSubscribedEvents(): array
    {
        return [PostRegistrationEvent::NAME => 'sendNotification'];
    }
    
    public function sendNotification(PostRegistrationEvent $event): void
    {
        $notification = ($this->notificationFactory($event->getUser());
        
        $this->notificationManager->send([$notification]);
    }
}

Fix:

public function sendNotification(PostRegistrationEvent $event): void
    {
        $notification = ($this->notificationFactory)($event->getUser());
        $this->notificationManager->send(new \ArrayObject($notification));
    }

Thx, I'll go for an array though. Should have created two methods though, sendOne and sendMany ;)

I think you should just choose send One) One notification is sent more often. And a few can be done through foreach)