When someone is developing a package, they need to run the tests! Hence, you need to add the bob packages in test-requirements.txt in develop.cfg as well.

Also, as a norm that we use in bob packages, we list not only the bob packages that are used (in both requirements.txt and test-requirements.txt) but also their dependencies as well. To get the list of these packages, you can use bob_dependecy_graph.py from bob.extension. You need to run this on your package, bob.pad.face here and all ALSO on all packages in test-requirements.txt.