anchor.diff:  
       ok.
   
  +add_buckets_uuids_test() ->
  +    OldCfg1 = [[{buckets,
  +                 [{configs, []}]}]],
  +    ?assertEqual([],
  +                 maybe_add_buckets_uuids(OldCfg1)),
  +
  +    OldCfg2 = [[{buckets,
  +                 [{configs, [{"default", []}]}]}]],
  +    ?assertMatch([{set, buckets, [{configs, [{"default", [{uuid, _}]}]}]}],
  +                 maybe_add_buckets_uuids(OldCfg2)),
  +
  +    OldCfg3 = [[{buckets,
  +                 [{configs, [{"default", [{uuid, some_uuid}]}]}]}]],
  +    ?assertEqual([],
  +                 maybe_add_buckets_uuids(OldCfg3)),
  +
  +    OldCfg4 = [[{buckets,
  +                 [{configs, [{"default", []}]},
  +                  {other, other}]}]],
  +    ?assertMatch([{set, buckets, [{configs, [{"default", [{uuid, _}]}]},
  +                                  {other, other}]}],
  +                 maybe_add_buckets_uuids(OldCfg4)),
  +
  +    OldCfg5 = [[{buckets,
  +                 [{configs, [{"default", [{bucket_prop, bucket_prop}]},
  +                             {"bucket", [{uuid, some_uuid}]}]},
  +                  {other, other}]}]],
  +    ?assertMatch([{set, buckets,
  +                   [{configs, [{"default", [{uuid, _},
  +                                            {bucket_prop, bucket_prop}]},
  +                               {"bucket", [{uuid, some_uuid}]}]},
  +                    {other, other}]}],
  +                 maybe_add_buckets_uuids(OldCfg5)),
  +
  +    OldCfg6 = [[]],
  +    ?assertEqual([],
  +                 maybe_add_buckets_uuids(OldCfg6)),
  +
  +    ok.
  +
   -endif.
  
positive.code:             [{set, vbucket_map_history, FinalHistory}]
      end.
  
  -ifdef(EUNIT).
  
  add_vbucket_map_history_test() ->
  
negative.code: 
  upgrade_config_from_pre_2_0_to_2_0(Config) ->
      ?log_info("Performing online config upgrade to 2.0 version"),
      maybe_add_vbucket_map_history(Config) ++
          maybe_add_buckets_uuids(Config).
  
  maybe_add_vbucket_map_history(Config) ->
      maybe_add_vbucket_map_history(Config, ?VBMAP_HISTORY_SIZE).
  