Python packaging scenarios by the creators of ruff

Hi!

I wrote this library / tool. Basically we needed a way to test arbitrary packaging situations and, instead of manually constructing packages or finding representative situations on PyPI, we wrote a tool that could construct them automatically and host the required dependency trees.

We use these scenarios in uv's test suite[1] (our package manager).

There was an initial attempt to use these scenarios for testing in pip itself, but we'd need to invest a bit more into the tool for it to be feasible since resolver behavior can be different but still "correct" based on implementation details.

[1]: https://github.com/astral-sh/uv/blob/main/crates/uv/tests/pi...

I think competition is good but I fail to see the problem with pip that these alternatives are trying to address! Since pyproject.toml became fully supported in pip it just strikes me as better than all the other alternatives including poetry etc

This is interesting. But still pretty early, right? (As in, no real docs, not ready for publication...)?

It looks like a start of a packages.lock.json kind of tool for dependency resolution eventually?

Or am I missing something?