We see this as one of the most important areas in which we can innovate and leapfrog native OS environments by offering testing that is just as cross platform as Codename One is. We aren't just announcing our own unit testing API, we are announcing a fully integrated test recorder to auto-generate GUI tests for your applications and run them on the simulator.
We will also integrate this exact same testing framework into our build server to seamlessly test device support for you in the future.
In the video above you can see me going through the process of recording a test for the kitchen sink and then running it in the simulator.
I'm sure I'm going to get this question so I'll hit it right now before it comes up. No the tests are not JUnit compatible and we haven't used another well known testing framework. The main logic behind this is that tools such as JUnit rely on reflection to work since they use annotations or method invocation without an interface. This doesn't mesh well with Codename One's device targets so we chose to implement something of our own.
You would have to write most of the test cases for Codename One anyway since the API/functionality would be pretty different.