$ git clone -n https://src.fedoraproject.org/rpms/rubygem-rails-controller-testing.git /var/lib/mock/f41-build-1093579-19988/root/chroot_tmpdir/scmroot/rubygem-rails-controller-testing
Cloning into '/var/lib/mock/f41-build-1093579-19988/root/chroot_tmpdir/scmroot/rubygem-rails-controller-testing'...
$ git fetch origin 6a8010483fd28ef61eddbaae73dfae5cc6d86a70:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/rubygem-rails-controller-testing
 * [new ref]         6a8010483fd28ef61eddbaae73dfae5cc6d86a70 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 6a80104 Eliminate use of obsolete %patchN syntax (#2283636)