PEP 739: specify how to handle conflicting installs

[FFY00]

• Change is either:
  • To a Draft PEP
  • To an Accepted or Final PEP, with Steering Council approval
  • To fix an editorial issue (markup, typo, link, header, etc)
• PR title prefixed with PEP number (e.g. PEP 123: Summary of changes)

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[hugovk]

(I've added the checklist to the PR description.)

This is an accepted PEP, so needs SC approval:

If changes based on implementation experience and user feedback are made to Standards track PEPs while in the Provisional or (with SC approval) Accepted state, they should be noted in the PEP, such that the PEP accurately describes the implementation at the point where it is marked Final.

https://peps.python.org/pep-0001/#pep-maintenance

Please can you ask the SC about this change?

[FFY00]

@pfmoore, per python/steering-council#341 and python/steering-council#343, could you make a decision on this? Since the 3.15 feature freeze is just around the corner, I really don't want to have to wait for the Packaging Council to be up to speed.

[pfmoore]

There's one edge case that I'd like to clarify before accepting.

Suppose that a distribution has two Python builds that both get installed into the same prefix, but only one is actually installed by the user. From a strict reading, that one installation would need to be named build-details.json, and only if/when a second build got installed, would the new text apply. This would be problematic, because it would require renaming of the original build-details.json.

It's arguable that the "UNLESS unfeasible due to technical limitations" exclusion applies here, and the potential to install two builds is considered enough of a technical limitation. But if it's too easy to justify using a different name, that dilutes the benefit of having an easily discoverable standard name for common cases, so allowing that could be a bad idea.

Could you update the wording to clarify the intent in this case, please?