Including companion dependency only for specific versions of another dependency

[gerbenoostra]

• I have searched the issues of this repo and believe that this is not a duplicate.
• I have searched the FAQ and general documentation and believe that my question is not already covered.

Feature Request

I have an optional dev dependency (a companion package containing stubs), which I only want to include for certain versions of a main dependency.

For example, when using pyspark~=3.0, I want to use the pyspark-stubs~=3.0. However, when using pyspark~=3.3., I don't want to (as that package already includes the stubs).

My attempt:

[tool.poetry.dependencies]
pyspark = [
  {version = "~3.0", optional = true, python = "<=3.8"},
  {version = "~3.3", optional = true, python = ">3.8"}
]

[tool.poetry.group.test.dependencies]
pyspark-stubs = {version = "~3.0", python = "<=3.8", optional=true}

Which fails to resolve, as pyspark-stubs depends on pyspark ~3.0, and the project depends on both pyspark ~3.0 and pyspark ~3.3.

The problem in this case is of course that for pyspark 3.3, there's no compatible pyspark-stubs specified. But in this case, I want the resolution to not use any pyspark-stubs. I tried to enforce this by using the same restriction on python, but that didn't work.

How can I specify such a companion dependency (like stubs) only for specific versions of my main dependency? Or is there a way to group them together in another way?

[dimbleby]

duplicate #8499, both seem unlikely ever to happen

[gerbenoostra]

It does work with transitive dependencies though, I assume.

If I depend on library A version 1 or 2, where version 1 has different dependencies than 2, depending on the version (perhaps based on python version), either the set of 1 or the set of 2 would get installed.

Maybe I can create a workaround where I release 2 versions of a private (empty) package: one with pyspark 3.0 & pyspark-stubs as dependencies, and release another new version that depends only on pyspark 3.3.

[radoering]

Which fails to resolve, as pyspark-stubs depends on pyspark ~3.0, and the project depends on both pyspark ~3.0 and pyspark ~3.3.

If I understand correctly this example should resolve because the intersection of the markers of pystark-stubs and pyspark ~ 3.3 is empty. However, this example might be a duplicate of #5506.

Maybe I can create a workaround where I release 2 versions of a private (empty) package: one with pyspark 3.0 & pyspark-stubs as dependencies, and release another new version that depends only on pyspark 3.3.

You may run into the same solver issue or it may work. I'd like to hear whether this changes anything. 🙂