PEP 639, Round 3: Improving license clarity with better package metadata

[brettcannon]

@henryiii

If license.file is specified and the metadata version is 2.4+, the build backend is supposed to issue a warning and fill License-File with the file path. But what should it do with License? Also fill it with the contents, or leave it off? Unless I’m mistaken, the PEP seems to miss this detail.

I don’t know if I would classify it as “missed” so much as “doesn’t take a position”.

@ksurma

PEP doesn’t forbid performing the “legacy” transformations as they were done so far, so in my opinion you could generate License field as usual and optionally (but encouraged by SHOULD) use the file to populate the License-File field.

The question is whether not defining it in dynamic in any way influences things? Since you can’t fill in both if you specify license in dynamic then I think it’s a gray area. I personally think back-ends can fill it in or leave it out.

But I will say the License field is a bit of a mess due to the lack of clear specification of how to do multi-line strings in METADATA (we really need to start transitioning to JSON).