$ git clone -n https://src.fedoraproject.org/rpms/rs.git /var/lib/mock/f40-build-752655-116816/root/chroot_tmpdir/scmroot/rs
Cloning into '/var/lib/mock/f40-build-752655-116816/root/chroot_tmpdir/scmroot/rs'...
$ git fetch origin a4c497c77a932381d5585dcfeb0d67a806803ffd:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/rs
 * [new ref]         a4c497c77a932381d5585dcfeb0d67a806803ffd -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at a4c497c Initial import