Deprecating [pyproject] optional-dependency

[LecrisUT]

Since pyproject is effectively an empty optional-dependency, should it be deprecated and removed eventually? I'm not sure how to query the dependencies on PyPI, but for Fedora there are a couple that would nee patching:

$ fedrq wr python3-scikit-build-core+pyproject
python-cascadio-0.0.13-1.fc41.src
python-llama-cpp-python-0.2.75-6.fc41.src

[henryiii]

It's there for a while since it pip will produce a warning if users request it and it's not there. But I think we can remove it soon or maybe even next release.

[LecrisUT]

Unfortunately users probably ignore warnings until the last second. 72 hits that I was able to find: https://sourcegraph.com/search?q=context:global+scikit-build-core%5B&patternType=keyword&sm=0

[henryiii]

What's the "last second"? Unless pip makes this an error, it's always been a warning to request an extra that doesn't exist. And we can't add a warning any other way.

[LecrisUT]

Well since this is only observed at the build time, they would only see it in the CI, which they would generally be ignoring, until the optional dependency is actually removed causing errors. I will probably add -Werror to my various CI builds as well after thinking about this.

[henryiii]

optional dependency is actually removed causing errors

That's the point, removing the optional dependency causes warnings, not errors.

. I will probably add -Werror to my various CI builds as well after thinking about this.

This is a pip warning, not a Python warning. (Though, that's a really good idea in general, and recommended at https://learn.scientific-python.org/development/guides/pytest/#configuring-pytest).

[henryiii]

See scikit-build-core[color], for example.