I posted a fix for this yesterday. The break was caused by a change in
behaviour of parse_commit that the --merge-order stuff was dependent
on. Now that parse_commit is sane, the --merge-order stuff needs to be
made sane too.
The fix was in this patch.
[PATCH 1/1] Fix --merge-order unit test breaks introduced by
6c88be169881c9223532796bd225e79afaa115e1
jon.