Comments on: TDD: Helper for checking PropertyChanged event gets raised

By: Drew Freyling

Drew Freyling — Fri, 25 Sep 2009 05:53:58 +0000

Yeah but you are only making your assertion in the dispose of your event listener. So your test while it will pass, won’t make the assertion unless you dispose of it in your test.

By: Richard

Richard — Wed, 09 Sep 2009 00:59:09 +0000

Drew: our app used the WPF MVVM toolkit; view models inherit ViewModelBase which isn’t IDisposable..?

By: Drew Freyling

Drew Freyling — Tue, 08 Sep 2009 08:39:30 +0000

Ah. The viewmodel must also implement idisposable which would then in turn dispose of the event listener and make the assertion. For example:

using (var viewModel = new ViewModel()) {
viewModel.AssertRaisesPropertyChangedFor(“PackPath”);
viewModel.OnFileSelected(@”C:\foo.zip”);
}

By: Richard

Richard — Wed, 26 Aug 2009 02:06:31 +0000

Drew,

It worked on my machine, I promise!! Perhaps the dispose/finalizer needs to be tweaked for your environment/test runner?

By: Drew Freyling

Drew Freyling — Wed, 19 Aug 2009 23:29:32 +0000

Are you sure this works? when i run the test it keeps hitting the finalize and never the dispose, therefore never making the assertion.

By: Richard

Richard — Thu, 21 May 2009 10:58:08 +0000

@Beau: I got sick of typing that over and over again :)

By: Beau Crawford

Beau Crawford — Mon, 11 May 2009 14:19:15 +0000

I use the following for testing events:

bool wasCalled = false;
viewModel.PropertyChanged += (s, e) => { wasCalled = true; }

// Invoke action that raises event

Assert.IsTrue(wasCalled);