$ git clone -n https://src.fedoraproject.org/rpms/golang-github-robertkrimen-otto.git /var/lib/mock/f40-build-2236539-53513/root/chroot_tmpdir/scmroot/golang-github-robertkrimen-otto
Cloning into '/var/lib/mock/f40-build-2236539-53513/root/chroot_tmpdir/scmroot/golang-github-robertkrimen-otto'...
$ git fetch origin e679eecfbaec38a11f1f5b7ba5fc0cdff72df030:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/golang-github-robertkrimen-otto
 * [new ref]         e679eecfbaec38a11f1f5b7ba5fc0cdff72df030 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at e679eec Remove deprecated %patchN syntax