$ git clone -n https://src.fedoraproject.org/rpms/ocaml-ppxlib.git /var/lib/mock/f40-build-784016-133242/root/chroot_tmpdir/scmroot/ocaml-ppxlib
Cloning into '/var/lib/mock/f40-build-784016-133242/root/chroot_tmpdir/scmroot/ocaml-ppxlib'...
$ git fetch origin d393a406df4a999a343b860f95a9b763abfc06d8:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/ocaml-ppxlib
 * [new ref]         d393a406df4a999a343b860f95a9b763abfc06d8 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at d393a40 Bump and rebuild