$ git clone -n https://github.com/xcp-ng-rpms/sm.git /var/lib/mock/v8.3-incoming-9414-28151/root/chroot_tmpdir/scmroot/sm
Cloning into '/var/lib/mock/v8.3-incoming-9414-28151/root/chroot_tmpdir/scmroot/sm'...
$ git fetch origin 87c99efcacd6e3c3b076e2930dd7c402e1d19494:KOJI_FETCH_HEAD
From https://github.com/xcp-ng-rpms/sm
 * [new ref]         87c99efcacd6e3c3b076e2930dd7c402e1d19494 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 87c99ef Merge pull request #86 from xcp-ng-rpms/dtt-fix-largeblock