Comment by shonigmann for Hi all,I am writing some tests for my ROS2 Python package. I want to specify different levels of tests (unittest, integrationtests, system tests, ...) and run them with colcon test . I have the different tests in subfolders in the test directory:my_pkg ├── launch │   └── example.launch.py ├── my_pkg │   ├── __init__.py │   ├── my_node.py │   ├── publisher.py │   ├── subscriber.py │   └── transformer.py ├── package.xml ├── README.md ├── resource │   └── my_pkg ├── setup.cfg ├── setup.py └── test ├── integrationtest │   └── test_integration.py └── unittest ├── test_pytest.py └── test_unittest.py Colcon detects all tests, what is great. But sometimes I only want run e.g. the tests in the directory unittests. That woult be useful, because some of my integration or system tests needs a long time!Are there any possibilities to run a specific subfolder of the test directory with colcon test? Have colcon some command line arguments for this? Or is there another way to go?

Someone can correct me if I am wrong, but from my understanding of `colcon test`, there isn't a built-in way of selecting to only run tests from a given sub-folder of a package. A workaround that comes to mind would be to create sub-packages (e.g. `my_pkg_integrationtest`, `my_pkg_unittest`) and to list them in `my_pkg`'s `package.xml` as test_dependencies. But I'd be surprised if there wasn't someone more knowledgeable out there with a better solution than that