Running pytest with coverage for tests against multiprocessing.Pool generates several data files, but not all of them are cleaned after. It looks similar to #100.
Pool.join() doesn't seem to change anything.
Example filename .coverage.myhost.local.7582.948066

Here's the repository to reproduce: https://github.com/manycoding/pytest_cov_pool_datafiles_250

Your operating system name and version:
Mac OS Mojave 10.14 (18A391)

Any details about your local setup that might be helpful in troubleshooting:

pipenv shell; pipenv install

Pipfile

pytest = "*"
pytest-cov = "*"
pytest-mock = "*"
tox-pipenv = "*"
pytest-pythonpath = "*"

Detailed steps to reproduce the bug:

pytest --cov=src --cov-report=term-missing  tests/test_cov_pool.py