This isn't a port - it's a re-implementation without any use of the original source.

That's also not all that's happening. It's also making improvements like better internalization support, better error messages, and a small handful of other extensions.

I have had to tell them repeatedly to stop copying tests verbatim, including the original comments from GNU coreutils. So I doubt this is true, which is frustrating.

What's wrong with them using the coreutils tests?

If they followed the license nothing. My uninformed knowledge is that the rust based rewrite is MIT, the originals are GPL, and you can't include GPL code in a MIT licensed project without making it GPL.

> and you can't include GPL code in a MIT licensed project without making it GPL.

Why is that? The tests are not linked to the distributed binaries. You can also distribute project sources with mixed licenses.

But you should be able to use a GPL test suite on an MIT-licensed program (or even a proprietary one, without the program needing to be under the GPL.

Ehh... Technically yes but when you don't own the copyright on the tests you need to be very careful against creating derivative works, and you need to preserve both licenses in the distributed source.