All files deselected when running pytest -m pylint --pylint

[jpsamper2009]

Between 0.15.0 and 0.16.0 there was a change in the way that an empty ignore_patterns= is parsed from the .pylintrc. Starting with 0.16.0, ignore patterns gets loaded as an empty string'', which matches all files, deselecting all from analysis:

platform darwin -- Python 3.7.5, pytest-5.4.1, py-1.8.1, pluggy-0.13.1
...
plugins: pylint-0.17.0, cov-2.8.1
collected 26 items / 26 deselected 

The solution is to comment out the empty ignore_patterns= entry in the .pylintrc:

platform darwin -- Python 3.7.5, pytest-5.4.1, py-1.8.1, pluggy-0.13.1
...
plugins: pylint-0.17.0, cov-2.8.1
collected 38 items / 26 deselected / 12 selected

Side note: I'm not sure if this is a bug or just an API change, but I had trouble finding any information about it. The closest was #89, but I think it was a different root cause.

[pederser]

A possible solution could be: plugin.py around line 144

        try:
            ignore_patterns_string = self.pylint_config.get('MASTER', 'ignore-patterns')
            if ignore_patterns_string:
                self.ignore_patterns = ignore_patterns_string.split(',')
        except (NoSectionError, NoOptionError):
            pass

        # try:
        #     self.pylint_ignore_patterns = self.pylint_config.get(
        #         'MASTER', 'ignore-patterns'
        #     ).split(',')
        # except (NoSectionError, NoOptionError):
        #     pass