1

我有一个 ViewModel，它开始在构造函数中异步加载模型，并在加载模型时触发一个事件。我得到了一个使用 silverlight 单元测试框架的测试，如下所示：

bool done = false;

[TestMethod]
[Asynchronous]
public void Test_NoCustomerSelected()
{
    ProjectListViewModel viewModel = null;
    EnqueueCallback(() => viewModel = new ProjectListViewModel());
    EnqueueCallback(() => viewModel.ModelLoaded += new EventHandler<EventArgs>(viewModel_ModelLoaded));

    EnqueueConditional(() => done);
    EnqueueCallback(() => Assert.IsNotNull(viewModel.FilteredProjectList));
    EnqueueCallback(() => Assert.AreEqual(4, viewModel.FilteredProjectList.Count));

    EnqueueTestComplete();
}

void viewModel_ModelLoaded(object sender, EventArgs e)
{
    done = true;
}

但我开始使用 Rx 框架，并试图让我的测试工作，但到目前为止我还没有运气。这是 2 次尝试：

public void Test_NoCustomerSelected2()
{
    ProjectListViewModel viewModel = null;
    viewModel = new ProjectListViewModel(eventAggregatorMock.Object, moduleManagerMock.Object);

    IObservable<IEvent<EventArgs>> eventAsObservable = Observable.FromEvent<EventArgs>(
        ev => viewModel.ModelLoaded += ev,
        ev => viewModel.ModelLoaded -= ev);

    eventAsObservable.Subscribe(args => viewModel_ModelLoaded(args.Sender, args.EventArgs));
    eventAsObservable.First();

    Assert.IsNotNull(viewModel.Model);
    Assert.AreEqual(4, viewModel.Model.Count);
}

[TestMethod]
public void Test_NoCustomerSelected3()
{
    ProjectListViewModel viewModel = null;

    var o = Observable.Start(() => viewModel = new ProjectListViewModel(eventAggregatorMock.Object, moduleManagerMock.Object));

    IObservable<IEvent<EventArgs>> eventAsObservable = Observable.FromEvent<EventArgs>(
        ev => viewModel.ModelLoaded += ev,
        ev => viewModel.ModelLoaded -= ev);

    o.TakeUntil(eventAsObservable)
          .First();

    Assert.IsNotNull(viewModel.Model);
    Assert.AreEqual(4, viewModel.Model.Count);
}

第一个测试永远等待，第二个测试不起作用，因为 viewModel 在执行 FromEvent 时为空。

任何人都知道如何正确执行此操作？

更新：在 PL 的帮助下，这是一个可行的解决方案：

[TestMethod]
public void Test_NoCustomerSelected4()
{
    var viewModel = new ProjectListViewModel(eventAggregatorMock.Object, moduleManagerMock.Object); 

    Observable 
       .FromEvent<EventArgs>(viewModel, "ModelLoaded")) 
       .Take(1) 
       .Subscribe(e =>  
           { 
               Assert.IsNotNull(viewModel.Model); 
               Assert.AreEqual(4, viewModel.Model.Count); 
           }); 
}
4

1 回答 1

2

我相信您仍然必须使用 Enqueue 调用。例如这样的：

var done = false;
var viewModel = new ProjectListViewModel(eventAggregatorMock.Object, moduleManagerMock.Object);

Observable
   .FromEvent<EventArgs>(viewModel, "ModelLoaded"))
   .Take(1)
   .Subscribe(viewModel => 
       {
           Assert.IsNotNull(viewModel.Model);
           Assert.AreEqual(4, viewModel.Model.Count);
           done = true;
       });

EnqueueConditional(() => done);
EnqueueTestComplete();
于 2010-04-23T17:02:06.820 回答