When "python -m unittest discover" is run in a folder that is an implicit namespace package with the structure as below, no tests are discovered.
The condition that the tests must be importable from the top level directory is fulfilled and has been tested by importing the tests from the top level.

I did some investigating and have a PR underway that seems to fix it

Example project structure is:
.
├── requirements.txt
├── main.py
├── tests
    ├── unit
    │   └── test_thing1.py
    └── integration.py
        └── test_integration_thing1.py

Issue originally from SO: https://stackoverflow.com/questions/46976256/recursive-unittest-discovery-with-python3-and-without-init-py-files

Is this related to Issue 23882? That one is about making discovery work when “__init__.py” files are removed.

Martin: Yeah, they same to be same! Can't believe I didn't find it

Hi!

IMO its a good propose. You will have to modify some tests.

If this is truly a duplicate, this should be closed and the issue number in the pr title changed to 23882.  Any reviewer should look at both proposed fixes, as they are not the same.  The other patch has what looks like the beginning of a test.