$ git clone -n https://src.fedoraproject.org/rpms/python-pynest2d.git /var/lib/mock/f42-build-side-1-3500259-45970/root/chroot_tmpdir/scmroot/python-pynest2d
Cloning into '/var/lib/mock/f42-build-side-1-3500259-45970/root/chroot_tmpdir/scmroot/python-pynest2d'...
$ git fetch origin d9aecb99780ad651089ffb31d0468d9b6d4e9545:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/python-pynest2d
 * [new ref]         d9aecb99780ad651089ffb31d0468d9b6d4e9545 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at d9aecb9 Rebuild (NLopt)