$ git clone -n https://src.fedoraproject.org/rpms/golang-github-yudai-golcs.git /var/lib/mock/f40-build-2263913-54543/root/chroot_tmpdir/scmroot/golang-github-yudai-golcs
Cloning into '/var/lib/mock/f40-build-2263913-54543/root/chroot_tmpdir/scmroot/golang-github-yudai-golcs'...
$ git fetch origin b1a23a1924aa459ccaad98c3d9374910c4a22709:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/golang-github-yudai-golcs
 * [new ref]         b1a23a1924aa459ccaad98c3d9374910c4a22709 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at b1a23a1 Remove deprecated %patchN syntax