$ git clone -n https://gitee.com/src-opencloudos-rpms/trousers.git /var/lib/mock/dist-oc9-build-131477-78571/root/chroot_tmpdir/scmroot/trousers
Cloning into '/var/lib/mock/dist-oc9-build-131477-78571/root/chroot_tmpdir/scmroot/trousers'...
$ git fetch origin oc9:KOJI_FETCH_HEAD
From https://gitee.com/src-opencloudos-rpms/trousers
 * [new branch]      oc9        -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at ce0ef62 import trousers-0.3.15-6.tl4