hello Brain,

first of all, thank you for your fast response. As I mentioned, the
test-files in our system are directly embedded in a hierarchical launch-file
structure. This hierarchical structure has the advantage that a launch file
which groups other components already includes all test-files of its
dependencies. You can run all the tests for that high-level launch file as
easy as a test for a single one. The further advantage is that modifications
in low-level launch and test files would affect the high-level test-files as
well, so that no tests gets lost or outdated.
Therefore I'm looking for a way to run multiple tests at once without
restarting the whole system again and again while keeping the hierarchical
structure.

-Jannik