public async Task A_null_subscriber_causes_an_ArgumentNullException()
{
var dispatcher = Substitute.For <IDispatcher>();
var eventAggregator = new MessageAggregator();
Assert.ThrowsAsync <ArgumentNullException>(async() => await eventAggregator.SubscribeAsync(null));
}
public async Task A_valid_message_is_published_to_all_handlers()
{
var dispatcher = new XamlDispatcher();
var eventAggregator = new MessageAggregator();
var handler1 = Substitute.For <IHandleAsync <object> >();
var handler2 = Substitute.For <IHandleAsync <object> >();
var handler3 = Substitute.For <IHandle <object> >();
handler1.HandleAsync(Arg.Any <object>()).Returns(async(c) =>
{
Console.WriteLine(
$"{DateTime.Now} - Starting handler 1...");
await Task.Delay(3000);
Console.WriteLine(
$"{DateTime.Now} - Finished handler 1...");
});
handler3.When(c => c.Handle(Arg.Any <object>()))
.Do((c) =>
{
Thread.Sleep(500);
Console.WriteLine($"{DateTime.Now} - executing handler 3...");
});
handler2.HandleAsync(Arg.Any <object>()).Returns(async(c) =>
{
Console.WriteLine(
$"{DateTime.Now} - Starting handler 2...");
await Task.Delay(3000);
Console.WriteLine(
$"{DateTime.Now} - Finished handler 2...");
});
await eventAggregator.SubscribeAsync(handler1);
await eventAggregator.SubscribeAsync(handler2);
await eventAggregator.SubscribeAsync(handler3);
var message = new object();
await eventAggregator.PublishAsync(message);
#pragma warning disable 4014
handler1.Received().HandleAsync(message);
handler2.Received().HandleAsync(message);
handler3.Received().Handle(message);
#pragma warning restore 4014
}
public async Task True_returned_when_a_handler_exists_for_a_given_message()
{
var dispatcher = Substitute.For <IDispatcher>();
var handlerStub = Substitute.For <IHandle <object> >();
var eventAggregator = new MessageAggregator();
await eventAggregator.SubscribeAsync(handlerStub);
Assert.True(eventAggregator.HandlerExistsFor(typeof(object)));
}
public async Task A_valid_subscriber_is_assigned_as_a_handler_for_its_message_type()
{
var dispatcher = Substitute.For <IDispatcher>();
var handlerStub = Substitute.For <IHandleAsync <object> >();
var eventAggregator = new MessageAggregator();
Assert.False(eventAggregator.HandlerExistsFor(typeof(object)));
await eventAggregator.SubscribeAsync(handlerStub);
Assert.True(eventAggregator.HandlerExistsFor(typeof(object)));
}
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)));
}
