pre-commit: move prospector inside pre-commit

[humitos]

• removes prospector check from tox
• run prospector check inside pre-commit

This allows developers to auto-run prospector before pushing changes to GitHub and be able to fix these problems locally in a quicker way.

Requires: readthedocs/common#166

[benjaoming]

Yes please ❤️

The workflow of waiting for CI to lint things that aren't automatically linted locally is slow. So this will be a relative improvement and most welcome 👍

After doing this, I think we should seriously consider getting a much faster linting process, though. Having https://raw.githubusercontent.com/readthedocs/readthedocs.org/main/requirements/pip.txt inside pre-commit requirements also seems a bit dramatic.

[humitos]

Having https://raw.githubusercontent.com/readthedocs/readthedocs.org/main/requirements/pip.txt inside pre-commit requirements also seems a bit dramatic.

This is only executed once when the environment is created. Unfortunately, on CircleCI we have to install these requirements each time :/ --but I didn't find a better way of doing this for now. We can explore other alternatives in the future.

[benjaoming]

This is only executed once when the environment is created. Unfortunately, on CircleCI we have to install these requirements each time :/ --but I didn't find a better way of doing this for now. We can explore other alternatives in the future.

If it makes sense from build times, we could open an issue explore putting .pre-commit into a Circle CI cache. AFAIK, pre-commit manages its virtualenvs in a very sophisticated manner so it's quite likely that it could bootstrap from a cache and save to a cache afterwards.

[humitos]

It seems all of us are more or less on board with this change and the one in common/. We can tune it a little more as we go while finding things that are not working as we expect. Also, we can revert if we find it does not work at all.

I'm merging this PR and the one in common as well to start trying this out.

[benjaoming]

I think this sounds like a great call, and nothing that cannot be reverted if for some reason it doesn't perform well enough. It shouldn't have any impacts, otherwise since it's the same linter.

Because pre-commit is also a local tool, it's much easier to tweak and optimize, and all changes will automatically work in CI 👍