$ git clone -n https://src.fedoraproject.org/rpms/waf.git /var/lib/mock/f40-build-2720110-73035/root/chroot_tmpdir/scmroot/waf
Cloning into '/var/lib/mock/f40-build-2720110-73035/root/chroot_tmpdir/scmroot/waf'...
$ git fetch origin 2f013fac542a3763047c252697299e00972d594e:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/waf
 * [new ref]         2f013fac542a3763047c252697299e00972d594e -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 2f013fa Update to 2.0.27.