$ git clone -n https://src.fedoraproject.org/rpms/golang-github-google-28.git /var/lib/mock/f40-build-2674820-67756/root/chroot_tmpdir/scmroot/golang-github-google-28
Cloning into '/var/lib/mock/f40-build-2674820-67756/root/chroot_tmpdir/scmroot/golang-github-google-28'...
$ git fetch origin d2e565e5e7f39edd4784dd52cf504cf9e38b59de:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/golang-github-google-28
 * [new ref]         d2e565e5e7f39edd4784dd52cf504cf9e38b59de -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at d2e565e Added the README