I think this is not going to work when the scripts get packaged in the RPM. Take into accoun that in that case, the file is in the following directory (along with the test engine script itself):

```
[fermin@centollo x86_64]$ rpm -qlp contextBroker-tests-0.13.0-1.x86_64.rpm  | grep 'testDiff.py'
/usr/share/contextBroker/tests/testDiff.py
```