Requires-python conflicts inside a workspace

[bluss]

Workspaces seem to require that all members use the same requires-python. Maybe this can be relaxed, or a dedicated error can explain it.

Steps to reproduce

uv init --virtual root
cd root
uv init -p 3.11 a
uv init -p 3.12 b
uv sync

It should have set up two projects a, b in the same workspace with conflicting requires-python of >= 3.11 and >= 3.12.

Actual Behaviour

  × No solution found when resolving dependencies:
  ╰─▶ Because the requested Python version (>=3.11) does not satisfy Python>=3.12 and
      b==0.1.0 depends on Python>=3.12, we can conclude that b==0.1.0 cannot be used.
      And because only b==0.1.0 is available and you require b, we can conclude that the
      requirements are unsatisfiable.

      hint: The `requires-python` value (>=3.11) includes Python versions that are not
      supported by your dependencies (e.g., b==0.1.0 only supports >=3.12). Consider using
      a more restrictive `requires-python` value (like >=3.12).

Expected Behaviour

Logically, the combination of a and b is fine to use with any python >= 3.12. There would be a reason to emit error is if a depends directly on b.

This situation seems to happen quite easily. Not sure what's the best way to improve.

uv 0.2.31
platform: linux (x86_64)

[charliermarsh]

Right now we take the union of the versions. I think what you're suggesting is we could take the intersection...

[charliermarsh]

Thinking on this more, I think intersection is probably right here (as long as we reject trying to install at a lower version).