License for packaging

[LecrisUT]

I am trying to package this project for Fedora ¹ and we've encountered ambiguous license issue. The suggestion was that it should be licensed under (MIT OR Apache-2.0) AND Unicode-DFS-2016 due to scripts/unicode.py

There could be another possibility to simply exclude scripts/* from crate, but I am not sure if the generated code is under the same license Unicode license or not.

Footnotes

1. https://bugzilla.redhat.com/show_bug.cgi?id=2279853 ↩

[LecrisUT]

I was also pointed to this discussion which seems to suggest that the generated files would have to have the Unicode-DFS-2016 license attached iiuc.

[musicinmybrain]

It is tables.rs that I believe may actually be (additionally) subject to the license of the Unicode Character Database from which it is derived. The Python script – it could be excluded from the crate simply because it’s not used by cargo, but I don’t see a reason why it needs to be.

[decathorpe]

As far as I can tell, the situation here is very similar to the unicode-ident crate: https://crates.io/crates/unicode-ident

See also dtolnay/unicode-ident#9 where AND Unicode-DFS-2016 was added to package.license in Cargo.toml.

See also https://github.com/unicode-rs/unicode-xid/pull/32/files for a similar request for a different unicode-rs crate.

[musicinmybrain]

It was pointed out downstream that the license text here is Unicode-3.0, not Unicode-DFS-2016, and that Unicode-3.0 should indeed be the correct license for Unicode version 17 data.

[LecrisUT]

Thanks, what a (un?)fortunate chain of events. @Manishearth, would you consider this PR?