Unit tests with a WPF window

I recently encountered a problem when I ran unit tests for my WPF windows. I got this error:

One of the background threads threw exception:
System.Runtime.InteropServices.InvalidComObjectException: COM object that has been separated from its underlying RCW cannot be used.
  at System.Windows.Input.TextServicesContext.StopTransitoryExtension()
  at System.Windows.Input.TextServicesContext.Uninitialize(Boolean appDomainShutdown)
  at System.Windows.Input.TextServicesContext.TextServicesContextShutDownListener.OnShutDown(Object target, Object sender, EventArgs e)
  at MS.Internal.ShutDownListener.HandleShutDown(Object sender, EventArgs e)

To fix this error, add the following method to the class containing your tests:

[TestCleanup]
public void CleanUp()
{
    Dispatcher.CurrentDispatcher.InvokeShutdown();
}

With this fix, the error no longer occurs. Here is the link to the original solution: http://connect.microsoft.com/VisualStudio/feedback/details/318333/unit-tests-which-show-windows-cause-vstesthost-mstest-shutdown-crashes-in-vs-2008-rtm

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