public static void MixedIndividualOrCompleteAdditionRemoval()
{
var subscriber = new TestEventHandler();
var collection = new EventSubscriberCollection();
// add individually
Assert.True(collection.Add <NamedEvent>(subscriber));
Assert.True(collection.Add <TestEvent>(subscriber));
// remove all
Assert.True(collection.RemoveAll(subscriber));
// check individually
Assert.False(collection.Remove <NamedEvent>(subscriber));
Assert.False(collection.Remove <TestEvent>(subscriber));
// add all
Assert.True(collection.AddAll(subscriber));
// remove individually
Assert.True(collection.Remove <NamedEvent>(subscriber));
Assert.True(collection.Remove <TestEvent>(subscriber));
// check all
Assert.False(collection.RemoveAll(subscriber));
// add all
Assert.True(collection.AddAll(subscriber));
// remove some
Assert.True(collection.Remove <NamedEvent>(subscriber));
// remove rest
Assert.True(collection.RemoveAll(subscriber));
// check
Assert.False(collection.RemoveAll(subscriber));
}
public static void EventHandlingSuspension()
{
var queue = new TaskEventQueue();
Assert.False(queue.EventHandling.IsSuspended);
var subscriber = new TestEventHandler();
queue.Subscribers.AddAll(subscriber);
var evnt = new TestEvent();
queue.EventHandling.Suspend();
queue.Enqueue(evnt);
Thread.Sleep(SleepTime);
Assert.Null(subscriber.LastEventHandled);
queue.EventHandling.Resume();
Thread.Sleep(SleepTime);
Assert.AreSame(evnt, subscriber.LastEventHandled);
queue.BeginShutdown();
}
public static void AddRemoveAllEventHandlers()
{
var subscriber = new TestEventHandler();
var collection = new EventSubscriberCollection();
// invalid argument tests
Assert.Throws <ArgumentNullException>(() => collection.AddAll(null, weakRef: true));
Assert.Throws <ArgumentNullException>(() => collection.AddAll(null, weakRef: false));
Assert.Throws <ArgumentNullException>(() => collection.RemoveAll(null));
// can not remove, what's not there
Assert.False(collection.RemoveAll(subscriber));
// add
Assert.True(collection.AddAll(subscriber, weakRef: false));
Assert.False(collection.AddAll(subscriber, weakRef: false)); // subscribers only added once
Assert.False(collection.AddAll(subscriber, weakRef: true)); // the type of reference used does not change this
// remove
Assert.True(collection.RemoveAll(subscriber));
Assert.False(collection.RemoveAll(subscriber));
}
public static void StrongSubscriberReference()
{
var collection = new EventSubscriberCollection();
WeakReference <TestEventHandler> weakRef;
// register subscriber using strong references
// then release our strong reference
{
var subscriber = new TestEventHandler();
weakRef = new WeakReference <TestEventHandler>(subscriber);
collection.AddAll(subscriber, weakRef: false);
subscriber = null;
}
// garbage collection
GC.Collect();
GC.WaitForPendingFinalizers();
// we have proof that the collection did use strong references
Assert.True(weakRef.TryGetTarget(out _));
GC.KeepAlive(collection);
}
