Flake8/PEP-8 checks for PRs

[icemac]

See https://pep8speaks.com which provides a GitHub app to automatically check PRs for Flake8 violations.

Pros:

• Improved visibility of Flake8 violations in the PR (better than running a Flake8 job via TravisCI which only makes TravisCI red without telling that only Flake8 is violated)

Cons:

• Each repository needs a special config yaml file.

[dataflake]

IMHO a much better idea than a completely failing a Travis CI job. Travis CI should only fail if there are real issues.

[mgedmin]

pep8speaks looks very interesting! It will look even more appealing if they implement support for GitHub Checks API instead of spamming PRs with comments like coveralls used to do.

Each repository needs a special config yaml file.

https://github.com/OrkoHunter/pep8speaks/#configuration says "A config file is not required for the integration to work."

OTOH I don't know if the defaults are fine for ZF repos (e.g. apparently it uses pycodestyle instead of flake8 by default).

I wonder if we could submit an upstream PR to default to flake8 when it finds a flake8 section in setup.cfg?

[jugmac00]

For my own and my companies projects I use pre-commit, ie the commit fails when there are flake8 issues. So there is no big chance that only CI detects flake8 violations. But certainly, CI also does flake8 checks - via tox. And to complete the loop, one could trigger pre-commit from tox.

=> no external GitHub app dependencies
=> no more "please flake8" commits

[icemac]

We are adding tox environments to lint the code using https://github.com/zopefoundation/meta/blob/master/config/config-package.py.
So this issue will be solved over time as more packages are switched to the new template.