public void Observer_OC_TwoSubscribers_SubcribersCalled()
{
Newspaper_OC herald = new Newspaper_OC("Herald");
Subscriber_OC subscriber1 = new Subscriber_OC();
Subscriber_OC subscriber2 = new Subscriber_OC();
herald.RegisterObserver(subscriber1);
herald.RegisterObserver(subscriber2);
herald.NewIssue("issue number 1");
herald.NewIssue("issue number 2");
Assert.AreEqual(2, subscriber1.LatestIssueNumber);
Assert.AreEqual(2, subscriber2.LatestIssueNumber);
}
public void Observer_OC_SubscriberNotCalledAfterBeingRemoved()
{
Newspaper_OC herald = new Newspaper_OC("Herald");
Subscriber_OC subscriber1 = new Subscriber_OC();
herald.RegisterObserver(subscriber1);
// not called before being resistered:
herald.NewIssue("issue number 1");
herald.UnregisterObserver(subscriber1);
herald.NewIssue("issue number 2");
Assert.AreEqual(1, subscriber1.LatestIssueNumber);
}