Bartosz Ratajczyk builds a few SQL Server Integration Services unit tests with ssisUnit:
The result shows 1 test run, 1 test passed, 2 asserts run, 2 asserts passed.
Wait, what? We have prepared only one assert, why does it show two?
The second assert is: “Task Completed: Actual result (Success) was equal to the expected result (Success).“. Great. Where does it come from? Let’s find out.
This is a nice introduction to the topic; if you fuss about with SSIS packages, you should check this out.