Hackage's rendering of Licenses, or how to get GPL-3.0-or-later?

[juhp]

I think the rendering of package License fields on Hackage has changed?

For example GPL-3 is rendered as GPL-3.0-only on Hackage,
but the GPL-3 field in .cabal files also covers GPL-3-or-later for example.
Or maybe there is already a way to do it correctly?

[juhp]

Ah, I guess this is haskell/cabal#2547 and #385, so it requires Cabal 2.2.
Then presumably it only works with Cabal >= 2.2.

[gbaz]

old style licenses are i think converted to spdx ones when we render them. But the conversion function indeed converts gpl-3 to gpl-3 only: http://hackage.haskell.org/package/Cabal-2.2.0.1/docs/src/Distribution-License.html#licenseToSPDX

[gbaz]

(i.e. it does not cover 3-or-later)

[gbaz]

On second thought, maybe it isn't correct to render gpl3 to gpl-3-only. Rather, for the "only" conversion cases (where we err on the side of conservative in the conversion) we perhaps should be rendering the unconverted thing rather than introducing spurious choices.

[phadej]

Note that GPL-3.0 are registered into ghc-pkg (8.4+) database as GPL-3.0-only, so if authors really care, they should bump to cabal-version: 2.2 and use proper expression.

The SPDX team introduced GPL-3.0-only and GPL-3.0-or-later identifiers specifically to avoid confusion of what's meant by GPL-3.0 (and too subtle difference with GPL-3.0+, which we don't even accept to Hackage. One can write GPL-3.0-only+ though; which we can forbid to enter Hackage though - not sure if we actually do).

[gbaz]

Right, but the problem is we have a ton of packages which do have that confusion already. So my idea here is to not "force" a choice on the author, retroactively, but just allow that confusion to persist in older-style cabal files.

[gbaz]

Actually, starting to change my mind again. After reading through the gpl faq, it seems to me like the "ambiguity" in not specifying only or or-newer really isn't that ambiguous. Without an explicit "or newer" designation the only possible reading is "only". So I'm starting to think that until cabal 2.2 there really just was no way to say "or newer" and the status quo now just recognizes that fact...

[gbaz]

based on my last thinking in this thread and no further discussion, optimistically closing.