[JacobCoffee]

PEP440 does not contain a limit. Can we please add one?

things like https://pypi.org/project/uselesscapitalquiz/ happen without it, and other issues arise not least of which is user a11y related to trying to fit/show all of the wild versioning

stats from pypi:
we have 9.9mm releases, median version is 5 characters, 99th percentil is 20, and maximal is 217(!!)

I propose a 128 char cap, 100 would affect ~9 current releases some releases in the last months with ~110-115 char versioning which I honestly don't understand but... whatever! 128 is fine.

If you'd like to be restrictive, 32 or 64 would be nicer to handle from a designer/UI perspective.

 ┌──────────────┬───────────────────────────────┬─────────────────────────────────────────────────┐
 │ Proposed cap │ Stored versions exceeding cap │ PEP 440-valid normalized versions exceeding cap │
 ├──────────────┼───────────────────────────────┼─────────────────────────────────────────────────┤
 │ 32           │ 323                           │ 128                                             │
 ├──────────────┼───────────────────────────────┼─────────────────────────────────────────────────┤
 │ 64           │ 119                           │ 12                                              │
 ├──────────────┼───────────────────────────────┼─────────────────────────────────────────────────┤
 │ 100          │ 9                             │ 9                                               │
 ├──────────────┼───────────────────────────────┼─────────────────────────────────────────────────┤
 │ 128          │ 2                             │ 2                                               │
 └──────────────┴───────────────────────────────┴─────────────────────────────────────────────────┘

I am not certain on an edit being required to the PEP itself, I think adding a practical limit on PyPI regardless is possible but I would prefer to have it codified.

refs:

• No Constraint on Version Names Can Cause Issues pypi/warehouse#12483
• Version metadata field size limits pypi/warehouse#14965
• https://discuss.python.org/t/amend-pep440-to-limit-version-identifiers/109629

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📚 Documentation preview 📚: https://python-packaging-user-guide--2163.org.readthedocs.build/en/2163/

[notatallshaw]

Changes and clarifications to the spec are discussed first at https://discuss.python.org/c/packaging/14

After agreement, either clarifications are opened here or a PEP process is followed.

[JacobCoffee]

@notatallshaw Sure, i'll do that. i was directed here when asking how a change like this should be brought up

[JacobCoffee]

closing per DPO discussion - indexes can enact this via policy so I think its okay to no set a restriction for tools.

if we want this in the future, maybe we re-open but soften the language from MUST to SHOULD NOT?

[ncoghlan]

Per the discussion thread, I think a SHOULD NOT that emphasises that publishing tools and index servers MAY enforce the limit (in addition to the MUST NOT telling locking tools and installers to skip enforcing it) would be a reasonable addition.

The "ensure numeric segments fit within 64 bits" guidance would also be good to include.