Add a pyproject.toml and setup.cfg

[swt2c]

This enables building/installing without using deprecated setup.py (but setup.py is still available).

[flub]

I know there have been lots of changes on the packaging side in python. But I haven't been keeping up. Is currently one of the recommended approaches? How do you build sdist and wheel without invoking setup.py? And finally, if setup.py is not needed, is there any point in keeping it around?

In general I like the look of this and would be happy to get rid of an executable setup.py.

[swt2c]

Yes, this is one of the recommended approaches - although perhaps only if you're interested in keeping a setup.py around for now. That's what I did since it was consistent with pytest itself. It's also possible to get rid of setup.py, setup.cfg, and do everything in pyproject.toml.

To build sdist and wheel without using setup.py, the recommended approach is to use build. For example python -m build.

[flub]

Sounds good, I'd probably be fine with getting rid of setup.py entirely but this is also fine.