$ git clone -n https://src.fedoraproject.org/rpms/diffuse.git /var/lib/mock/f40-build-2276646-55174/root/chroot_tmpdir/scmroot/diffuse
Cloning into '/var/lib/mock/f40-build-2276646-55174/root/chroot_tmpdir/scmroot/diffuse'...
$ git fetch origin b826940949b9a4fe4e7b97e30b0f5575070f3536:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/diffuse
 * [new ref]         b826940949b9a4fe4e7b97e30b0f5575070f3536 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at b826940 Release 0.9.0