$ git clone -n https://src.fedoraproject.org/rpms/OpenSceneGraph.git /var/lib/mock/f41-build-775535-13521/root/chroot_tmpdir/scmroot/OpenSceneGraph
Cloning into '/var/lib/mock/f41-build-775535-13521/root/chroot_tmpdir/scmroot/OpenSceneGraph'...
$ git fetch origin f667f3b54163a98fa23a7aeb25b6d53287659cb3:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/OpenSceneGraph
 * [new ref]         f667f3b54163a98fa23a7aeb25b6d53287659cb3 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at f667f3b Rebuild (gdal)