$ git clone -n https://src.fedoraproject.org/rpms/waf.git /var/lib/mock/f40-build-2084847-50034/root/chroot_tmpdir/scmroot/waf
Cloning into '/var/lib/mock/f40-build-2084847-50034/root/chroot_tmpdir/scmroot/waf'...
$ git fetch origin cbefe1ec49ab6f9e51ea4db888c4664519d1a584:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/waf
 * [new ref]         cbefe1ec49ab6f9e51ea4db888c4664519d1a584 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at cbefe1e Update to 2.0.26.