Description
It is sometimes useful to "reset" all the --cov=X options passed in "so far", eg.
pytest --cov=app --cov-reset --cov=app/module
would only check for coverage on app/module instead of checking the coverage on all modules in app.
My particular use case is to allow getting coverage from both local pytest and tox runs (tox is slower :)), yet keep tox using the installed package:
pytest.ini:
[pytest]
addopts = . --cov=package --cov-report=term-missing
tox.ini:
[tox]
envlist = py37,py38,py39
[testenv]
commands =
pytest . --cov-reset --cov={envsitepackagesdir}/package
Without the reset option, tox runs will include coverage on both the installed package and local copy (which is always zero).
As a bonus, such a simple implementation of --cov-reset could even be used to replace --no-cov altogether (the only requirement being that --cov-reset has to go after all the --cov options), so it's more flexible and a much simpler implementation. However, one would have to think carefully about all the use cases for no-cov (debuggers are mentioned)
Here's a pull request if you think this is worthwhile: #459