I use pytest-cov, and I needed a reporting option to report simply the overall coverage percentage to the terminal at the end of a test run. The normal terminal reports are too long on my project, since they list every covered module on its own line, and this means I have to scroll up to see details on test failures, which is irritating. But I do want immediate feedback on the terminal on the overall coverage percentage, so that I know immediately if it's dropped below 100% (and then I can go check the HTML report for details).
Fortunately this is quite easy to implement, as coverage.report already returns the overall percentage as a float; it just requires adding a new option for cov_report. In this PR I've named this option "overall" but I am not attached to the name and will happily change it to whatever you like.
If this PR is accepted I will supply a matching PR for pytest-cov to add this as one of the choices for the --cov-report option.