$ git clone -n https://src.fedoraproject.org/rpms/golang-github-r3labs-diff-3.git /var/lib/mock/f38-build-side-42-init-devel-1407641-31344/root/chroot_tmpdir/scmroot/golang-github-r3labs-diff-3
Cloning into '/var/lib/mock/f38-build-side-42-init-devel-1407641-31344/root/chroot_tmpdir/scmroot/golang-github-r3labs-diff-3'...
$ git fetch origin c836b22f07f2478ec1e49d6499a7ee554bc4c74e:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/golang-github-r3labs-diff-3
 * [new ref]         c836b22f07f2478ec1e49d6499a7ee554bc4c74e -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at c836b22 Disable some tests