$ git clone -n https://src.fedoraproject.org/rpms/free42.git /var/lib/mock/f41-build-3155059-40677/root/chroot_tmpdir/scmroot/free42
Cloning into '/var/lib/mock/f41-build-3155059-40677/root/chroot_tmpdir/scmroot/free42'...
$ git fetch origin 0fdaed597c51aab40e500b380a5cd486303d3258:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/free42
 * [new ref]         0fdaed597c51aab40e500b380a5cd486303d3258 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 0fdaed5 Update to 3.1.12