This plugin produces coverage reports. Compared to just using coverage run this plugin does some extras: * Subprocess support: you can fork or run stuff in a subprocess and will get covered without any fuss. * Xdist support: you can use all of pytest-xdist's features and still get coverage. * Consistent pytest behavior. If you run coverage run -m pytest you will have slightly different sys.path (CWD will be in it, unlike when running pytest). All features offered by the coverage package should work, either through pytest-cov's command line options or through coverage's config file.