Version("1.0.0.dev1").is_prerelease is true, should be false

[JakeSummers]

Bug Report

v = Version("1.0.0.dev1")

assert v.is_devrelease == True
assert v.is_prerelease == True # Fails

Reproducibility

$ poetry run python --version
Python 3.11.5

 poetry show packaging
 name         : packaging
 version      : 23.2
 description  : Core utilities for Python packages

required by
 - black >=22.0
 - pytest *

[JakeSummers]

Looking at this a bit further, it looks like this is the desired behaviour:

See: https://packaging.pypa.io/en/stable/version.html#packaging.version.Version.is_prerelease

I suppose that dev and release candidate may be a subclass of a pre-release..

Question: Where can I find the definition of what a pre-release is?

[notatallshaw]

Question: Where can I find the definition of what a pre-release is?

https://packaging.python.org/en/latest/specifications/version-specifiers/#pre-releases

I think one could read just that part of the spec and say dev-releases are not pre-releases, unless they are dev-releases of pre-releases.

This is problamatic though because other parts of the spec clearly consider dev releases to be part of pre-releases:

Pre-releases of any kind, including developmental releases

IMO the spec should be updated for clarity here. But perhaps a packaging maintainer might want to weigh in.

[brettcannon]

IMO the spec should be updated for clarity here. But perhaps a packaging maintainer might want to weigh in.

I agree that the spec needs to be clarified before we make a breaking change in the meaning of is_prerelease, so someone would need to take this to https://discuss.python.org/c/packaging/ for clarification.

[notatallshaw]

As this question has come up a couple of times now I created such discussion: https://discuss.python.org/t/are-developmental-releases-a-type-of-pre-release/81666

If it's decided that dev-releases are a form of pre-release then one thing missing from packaging's current API is a way to distguish between a dev-release of a final release, and a dev-release of a pre-release, e.g. 1.0dev1 and 1.0a1dev1.