$ git clone -n https://src.fedoraproject.org/rpms/tslib.git /var/lib/mock/f42-build-3282353-41398/root/chroot_tmpdir/scmroot/tslib
Cloning into '/var/lib/mock/f42-build-3282353-41398/root/chroot_tmpdir/scmroot/tslib'...
$ git fetch origin ad4ade70b4f79eff228ffec2abe7a5288eb1d17b:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/tslib
 * [new ref]         ad4ade70b4f79eff228ffec2abe7a5288eb1d17b -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at ad4ade7 1.23