Hi, What is the best approach in unit testing a stateful DoFn? I've looked over the userstate_test.py in Beam repo, but those examples do not really apply to our case. In those tests, the DoFn used for testing are returning values from timer callbacks which does not really happen in reality. I am more interested in testing if a timer was triggered after the watermark advanced, or what is the state bag content at a specific time.
Actually it would really be nice to have some kind of documentation regarding testing and best practices in writing unit/integration tests for Beam pipelines. Thanks, Tudor