$ git clone -n https://src.fedoraproject.org/rpms/R-rgeos.git /var/lib/mock/f38-build-side-42-init-devel-911759-28695/root/chroot_tmpdir/scmroot/R-rgeos
Cloning into '/var/lib/mock/f38-build-side-42-init-devel-911759-28695/root/chroot_tmpdir/scmroot/R-rgeos'...
$ git fetch origin a41071aa72d9077bf51b72a40e446adf6bbc1557:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/R-rgeos
 * [new ref]         a41071aa72d9077bf51b72a40e446adf6bbc1557 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at a41071a update to 0.6-2