packaging 22+ break PackagingSpecifierSet with extended version

[gsemet]

Was working with packaging 21.3:

SpecifierSet(f"<0.0.1.dev1+g3cdcc", prereleases=True)

In all versions since 22.0, we get:

packaging.specifiers.InvalidSpecifier: Invalid specifier: '<0.0.1.dev1+g3cdcc'

For me, 0.0.1.dev1+g3cdcc and 0.0.1.dev1 and equivalent so i do not understand why 0.0.1.dev1+g3cdcc is refused by SpecifierSet

[pradyunsg]

Please see #530

[pradyunsg]

Wait, I should elaborate.

In #530, there's discussion about why invalid inputs are now rejected by packaging. As for why this is invalid input, from the version specificiation for the operator being used:

Local version identifiers are NOT permitted in this version specifier.

So, the new behaviour here is correct. Further, packaging 21.3 returned a LegacySpecifier...

>>> list(SpecifierSet("<0.0.1.dev1+g3cdcc"))
[<LegacySpecifier('<0.0.1.dev1+g3cdcc')>]

... and packaging 21.3 also raises a warning when run in development mode.

❯ python -X dev -c "from packaging.specifiers import SpecifierSet; SpecifierSet('<0.0.1.dev1+g3cdcc')"
/Users/pradyunsg/Developer/github/pip/.venv/lib/python3.11/site-packages/packaging/specifiers.py:255: DeprecationWarning: Creating a LegacyVersion has been deprecated and will be removed in the next major release
  warnings.warn(

Closing this out since the question asked has been answered, and I don't expect that we'd be changing behaviour here unless someone reckons this is worth doing a standard specification update for + drives that effort.