Uli,
it seems that Mark has gone to his trip already, hence stepping in: the unit test framework is
modelled after junit (cf. the numerous materials there). The tests just have the purpose to assess
that they succeed or fail and should only report, if the expectations of a test would not be met,
ie. that the program (suddenly?) does not behave as at the time when the tests got created.
The framework is not meant to give by default "deep information" like call stacks, source code and
the like. If you wanted, you could add such a functionality. However, usually it is more than
sufficient to see whether the tests pass in the intended way. If some do not pass the report givng
test and the file is usually more than sufficient to locate the test and study it.
HTH,
---rony