In Memory Service Examples you don't require Mocks

InMemoryDomainEventDispatcher.php

<?php

declare(strict_types=1);

namespace App\Tests\Unit;

use Sulu\Bundle\ActivityBundle\Application\Collector\DomainEventCollectorInterface;
use Sulu\Bundle\ActivityBundle\Domain\Event\DomainEvent;

class InMemoryDomainEventDispatcher implements DomainEventCollectorInterface
{
    /**
     * @var DomainEvent[]
     */
    private array $domainEvents = [];

    public function collect(DomainEvent $domainEvent): void
    {
        $this->domainEvents[] = $domainEvent;
    }

    public function clear(): void
    {
        throw new \RuntimeException('Not implemented');
    }

    public function dispatch(): void
    {
        throw new \RuntimeException('Not implemented');
    }

    /**
     * @return DomainEvent[]
     */
    public function getDomainEvents(): array
    {
        return $this->domainEvents;
    }
}

InMemoryEventDispatcher.php

<?php

declare(strict_types=1);

namespace App\Tests\Unit;

use Psr\EventDispatcher\EventDispatcherInterface;

class InMemoryEventDispatcher implements EventDispatcherInterface
{
    /**
     * @var object[]
     */
    private array $events = [];

    public function dispatch(object $event): void
    {
        $this->events[] = $event;
    }

    public function clear(): void
    {
        $this->events = [];
    }

    /**
     * @return object[]
     */
    public function getEvents(): array
    {
        return $this->events;
    }
}

InMemoryMessageBus.php

<?php

declare(strict_types=1);

namespace App\Tests\Unit;

use Symfony\Component\Messenger\Envelope;
use Symfony\Component\Messenger\MessageBusInterface;
use Symfony\Component\Messenger\Stamp\HandledStamp;

/**
 * Used inside tests of process manager or unit tests of controller to check if a certain message was dispatched.
 */
class InMemoryMessageBus implements MessageBusInterface
{
    /** @var object[] */
    private array $messages = [];

    public function dispatch(object $message, array $stamps = []): Envelope
    {
        if ($message instanceof Envelope) {
            $envelope = $message;
            $message = $message->getMessage();
        } else {
            $envelope = new Envelope($message, $stamps);
        }

        $this->messages[] = $message;

        $envelope = $envelope->with(new HandledStamp(new \stdClass(), \stdClass::class));

        return $envelope;
    }

    /** @return object[] */
    public function getMessages(): array
    {
        return $this->messages;
    }
}

InMemoryTranslator.php

<?php

declare(strict_types=1);

namespace App\Tests\Unit;

use Symfony\Contracts\Translation\TranslatorInterface;

class InMemoryTranslator implements TranslatorInterface
{
    /**
     * @param array<string, string> $messages
     */
    public function __construct(
        private array $messages,
    ) {
    }

    public function trans(string $id, array $parameters = [], ?string $domain = null, ?string $locale = null): string
    {
        return $this->messages[$id] ?? $id;
    }

    public function getLocale(): string
    {
        return 'en';
    }
}

z-others.php

// Flysystem Memory Adapter: https://github.com/thephpleague/flysystem-memory
// Seal Memory Adapter: https://github.com/schranz-search/seal-memory-adapter
// Mock Http Client: https://symfony.com/doc/current/http_client.html#testing
//    The MockHttpClient: can be used to replace PSR clients inside third party e.g. Brevo SDK, ...
//    So the SDK itself is tested and only the Http Request mocked
//    If possible you should still test external APIs inside the CI and not mock them away
// Payment / Stripe:
//    Create your own PaymentInterface and have tested Functional and InMemory implementation for testing
// Log
//    PSR NullLogger if you don't care about the logs
//    Symfony BufferingLogger if you want get logged messages

// Things I still mock:
///
// Repositories
//    See https://danielrotter.at/2023/09/22/avoid-mocking-repositories-by-using-in-memory-implementations.html if you want avoid also that
// Symfony FormFactory and FormBuilders:
//    Edge case should normally be part of your functional controller tests
//    In my case I have own Custom FormFactory services which are Unit tested to test Object normalization

// Things you should never mock or fake
//    Domain Objects / Entities
//    Value Objects
//    Symfony or PSR Request or Response
//    Events objects