I think this proposal needs further refinements.

IMO, a package, must BR: pkgconfig(foo) iff it uses pkg-config to detect/check "foo".

A package, which does not use pkg-config to detect/check "foo", must not BR. pkgconfig(foo).

Whether to BR: foo-devel or not, is independent of this question. It'll be redundant to BR: pkgconfig(foo) in most cases, but should not do much harm otherwise.

At lease, I don't see that BR: pkgconfig(foo) and BR: foo-devel need to be mutually exclusive.

Thanks for the feedback. I'm happy enough saying 'MUST' instead of 'SHOULD'.

I'm not sure it's really relevant to ban the use of unneeded BuildRequires:. If those aren't banned under an existing policy, they probably should be. But it doesn't hurt to add that, so I have done so.

I've also tried to clarify that it's OK to use foo-devel sometimes. You're right that theoretically it's orthogonal — '''BUT''' many people do use foo-devel instead of pkgconfig(foo) so the practical upshot would be that we remove one and replace it with the other, in most cases. So I don't want to remove ''all'' mention of the 'foo-devel' form of the requirement.

Draft updated...

https://fedoraproject.org/w/index.php?title=PackagingDrafts/PkgConfigBuildRequires&diff=346617&oldid=346325

revised draft approved (+1:7, 0:0, -1:0)