The Unit Test framework reports no tests found
Ensure you have called UnitTestSystem.RegisterUnitTestProvider(new XunitContrib.Runner.Silverlight.Toolkit.UnitTestProvider()); in your App.xaml.cs:Application_Startup.
The Silverlight Unit Test framework doesn't do any kind of automatic discovery of test providers. It has the mstest based provider hard-coded. We must add the xunit provider manually.
Third part support
See this page for more details on third party support