Change license identifier in project metadata to text

[mschoettle]

I'd like to propose changing the license metadata to text with the license identifier "Python-2.0" reflecting the content of the LICENSE file.

License scanning tools such as the one GitLab uses rely on the license field returned by the PyPI API which returns license: null for this package (JSON).

Related to #62

[cpython-cla-bot]

All commit authors signed the Contributor License Agreement.

[srittau]

Thanks, it makes sense to me to use a classifier here. The documentation for pyproject.toml says to use of the license classifiers from the classifiers list (minus the prefix). But I can't find "Python-2.0" on that list?

[mschoettle]

Unfortunately, the classifiers are ambiguous (or not complete) for some licenses (BSD, Python, Apache). See also here: pypa/trove-classifiers#17. It seems that the classifiers are not taken into account for the license field that the PyPI API returns. With the license being specified as proposed by this PR the API returns the license field.

There is also now PEP 639 (provisional) which aims to improve this.

[srittau]

I don't think we should use classifiers that contradict the official documentation. It's great to see that there's some progress to improve the license situation, but I'd prefer to wait until there's an officially accepted solution. But I'll defer the decision to @JelleZijlstra and @AlexWaygood here, as core developers and most active regarding typing_extensions.

[JelleZijlstra]

I am not very familiar with packaging arcana, but I'd prefer to avoid relying on any unspecified behavior, and instead use PEP 639 now that it's been provisionally accepted.

[srittau]

I am not very familiar with packaging arcana, but I'd prefer to avoid relying on any unspecified behavior, and instead use PEP 639 now that it's been provisionally accepted.

That's the most sensible approach, but I don't think flit supports PEP 639 yet.

[mschoettle]

Waiting for PEP 639 makes sense to me.

There is now a feature request for flit: pypa/flit#692

[AlexWaygood]

Has this been superseded by #507?

[mschoettle]

Looks like it. Although it uses the old syntax, not the new one introduced by PEP 639 I think.

[cdce8p]

Looks like it. Although it uses the old syntax, not the new one introduced by PEP 639 I think.

flit_core doesn't yet support the new syntax and would raise a ConfigError.