public async Task A_null_unsubscriber_causes_an_ArgumentNullException()
{
var dispatcher = Substitute.For <IDispatcher>();
var eventAggregator = new MessageAggregator();
Assert.ThrowsAsync <ArgumentNullException>(async() => await eventAggregator.UnsubscribeAsync(null));
}
public async Task A_valid_subscriber_gets_removed_from_the_handler_list()
{
var dispatcher = Substitute.For <IDispatcher>();
var handlerStub = Substitute.For <IHandleAsync <object> >();
var eventAggregator = new MessageAggregator();
await eventAggregator.SubscribeAsync(handlerStub);
Assert.True(eventAggregator.HandlerExistsFor(typeof(object)));
await eventAggregator.UnsubscribeAsync(handlerStub);
Assert.False(eventAggregator.HandlerExistsFor(typeof(object)));
}
