Example Event Sourced Process Manager & corresponding Unit Test

RegistrationProcessManager.php

<?php
declare(strict_types=1);
namespace Wwwision\UserRegistration\Domain;

use Neos\EventSourcing\ProcessManager\AbstractEventSourcedProcessManager;
use Wwwision\UserRegistration\Domain\Events\UserHasConfirmedRegistration;
use Wwwision\UserRegistration\Domain\Events\UserHasStartedRegistration;
use Wwwision\UserRegistration\Domain\Events\UserRegistrationWasFinalized;
use Wwwision\UserRegistration\Domain\Events\UserWasPromoted;

final class RegistrationProcessManager extends AbstractEventSourcedProcessManager
{
    /**
     * promotion period (in seconds). A user confirmation within this period leads to the user being promoted
     */
    const PROMOTION_PERIOD = 10;
    
    /**
     * @var string
     */
    private $userId;

    public function whenUserHasStartedRegistration(UserHasStartedRegistration $event): void
    {
        $this->registrationTimestamp = $event->getTimestamp();
    }

    public function whenUserHasConfirmedRegistration(UserHasConfirmedRegistration $event): void
    {
        if ($event->getTimestamp()->diff($this->registrationTimestamp)->s < self::PROMOTION_PERIOD) {
            $this->recordThat(new UserWasPromoted($event->getUserId()));
        }
        $this->recordThat(new UserRegistrationWasFinalized($event->getUserId()));
    }

    public function whenUserRegistrationWasFinalized(UserRegistrationWasFinalized $_): void
    {
        $this->registrationTimestamp = null;
    }

}

RegistrationProcessManagerTest.php

<?php
declare(strict_types=1);
namespace Wwwision\UserRegistration\Domain\Tests\Unit;

use Neos\Flow\Tests\UnitTestCase;
use Wwwision\UserRegistration\Domain\Events\UserHasConfirmedRegistration;
use Wwwision\UserRegistration\Domain\Events\UserHasStartedRegistration;
use Wwwision\UserRegistration\Domain\Events\UserRegistrationWasFinalized;
use Wwwision\UserRegistration\Domain\Events\UserWasPromoted;
use Wwwision\UserRegistration\Domain\RegistrationProcessManager;

class RegistrationProcessManagerTest extends UnitTestCase
{
    /**
     * @var RegistrationProcessManager
     */
    private $processManager;

    public function setUp()
    {
        $this->processManager = new RegistrationProcessManager();
    }

    /**
     * @test
     */
    public function registrationIsFinalizedAfterUserConfirmation()
    {
        // arrange
        $this->processManager->whenUserHasStartedRegistration(new UserHasStartedRegistration('userId', 'foo@bar.com', new \DateTimeImmutable('2018-01-01 15:30:30')));
        $this->processManager->pullUncommittedEvents();

        // act
        $this->processManager->whenUserHasConfirmedRegistration(new UserHasConfirmedRegistration('userId', new \DateTimeImmutable('2018-01-01 15:30:40')));

        // assert
        $events = $this->processManager->pullUncommittedEvents();
        $this->assertThat($events, $this->countOf(1));
        $this->assertThat($events[0], $this->isInstanceOf(UserRegistrationWasFinalized::class));
    }

    /**
     * @test
     */
    public function userIsPromotedIfUserConfirmsWithinPromotionPeriod()
    {
        // arrange
        $this->processManager->whenUserHasStartedRegistration(new UserHasStartedRegistration('userId', 'foo@bar.com', new \DateTimeImmutable('2018-01-01 15:30:30')));
        $this->processManager->pullUncommittedEvents();

        // act
        $this->processManager->whenUserHasConfirmedRegistration(new UserHasConfirmedRegistration('userId', new \DateTimeImmutable('2018-01-01 15:30:39')));


        // assert
        $events = $this->processManager->pullUncommittedEvents();
        $this->assertThat($events, $this->countOf(2));
        $this->assertThat($events[0], $this->isInstanceOf(UserWasPromoted::class));
        $this->assertThat($events[1], $this->isInstanceOf(UserRegistrationWasFinalized::class));
    }
}