public function testCanDetachObservers()
{
$event_store = new EventStore(new EventStoreConfig());
$observer = new TestEventListener();
$detached_observer = new TestEventListener();
$identifier = new Identifier('Unit-Test-ID');
$event = new UnitTestEvent($identifier, 'Unit-Test');
$event_store->attachEventListener($observer);
$event_store->attachEventListener($detached_observer);
$collection = new EventEnvelopeCollection();
$collection[] = new EventEnvelope($event, []);
/** @var EventEnvelopeCollection $collection */
$event_store->commitEvents($collection);
$event_store->detachEventListener($detached_observer);
/** @var EventEnvelopeCollection $collection */
$event_store->commitEvents($collection);
$this->expectOutputString(UnitTestEvent::class . " with ID Unit-Test-ID was committed.\n" . UnitTestEvent::class . " with ID Unit-Test-ID was committed.\n" . UnitTestEvent::class . " with ID Unit-Test-ID was committed.\n");
}
