PEP 735: Dependency Groups in pyproject.toml

[matterhorn103]

@charliermarsh

is there a clear write-up anywhere on why dependency groups are necessary in lieu of a single section for development dependencies?

@baggiponte

Why creating a new table [dependency-groups] when it could just be [project.dev-dependencies]?

@AgentK9

I think that dev-dependency-groups would be much clearer

@sirosen

If this section isn’t prominent enough in the PEP, please say so. Maybe it can be called out earlier (e.g. in the abstract with minimal fuss)

I thought personally that reading the motivation section and first part of rationale makes it pretty clear that there are two key things you (@sirosen) are seeking to address:

1. dev dependencies
2. non-package/wheel dependencies

and as someone interested in the second case, and as someone who followed the previous thread closely, I thought it was fairly obvious that “non-package projects” might be things that aren’t developed per se, and therefore don’t have the concept of dev dependencies.

But maybe it’s only obvious to me/people who care about that second case, so given the comments asking otherwise, maybe it would indeed make sense to link to the use cases appendix earlier on.

Maybe it’s even worth stressing somewhere early on that “development” is not really even a relevant concept for many non-wheel projects, and that all that use cases like the data science one are crying out for is some sanctioned way to specify runtime dependencies or environment/project requirements or any other arbitrary dependency list in pyproject.toml.

Maybe there should even be a “Why not just add a dev-dependencies table?” entry in rejected ideas.