Looking for some good references on creating best practice unit tests with MVVM

I'm tasked with creating a unit test suite for a WPF solution that employs the MVVM design pattern. I'm looking for any references to help get me started on the right path, especially any references that focus on some best practices for testing view models.

Some of the 开发者_StackOverflow社区particular testing challenges of these view models is in testing the dialog workflows and mediator messages that are passed between some of the view models.

Thanks for your help.

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Prism comes with a reference implementation Stock Trader, it has extensive tests written for all its modules. Its a very good place to start. Install May 2010 guidance and look for the folder RI.