How to use the pytest_xdist_make_scheduler hook

[ghost]

I have tried to implement a custom test distribution logic for my test suite based on this suggestion: #18 (comment).

from xdist.scheduler import LoadScopeScheduling


class FixtureScheduling(LoadScopeScheduling):
    """Split by [] value. This is very hackish and might blow up any time!
    """
    def _split_scope(self, nodeid):
        if '[' in nodeid:
            return nodeid.rsplit('[')[-1].replace(']', '')
        return None


def pytest_xdist_make_scheduler(log, config):
    return FixtureScheduling(config, log)

I could make the logic a bit more robust, but for now I do not seem to be able to get this to work. I have both tried to adding this to the specific test file where this is needed and tried adding this to the conftest.py file, but neither seems to have any effect and it seems that the default scheduler is used regardless. I may have misunderstood how to use these pytests hooks, so any help is highly appreciated.