When writing Unit tests one can focus on two different aspects of the code under test. We can call these two types of test ‘State-based’ and ‘Interaction-based’. The first of these concentrates on the end result achieved by the code under test – ie, what was the result of the code being run, whereas the second focuses on how that result was achieved.

Our automated deployment of a CRM Solution file started failing with this error recently: 
"importjob With Id = feb7b87f-1ff9-4914-ba14-0116ca959584 Does Not Exist"
It was quite a journey to find out what was causing the error.