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: 
  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_vbucket_map_history(Config) ->
      maybe_add_vbucket_map_history(Config, ?VBMAP_HISTORY_SIZE).
  
negative.code:             [{set, vbucket_map_history, FinalHistory}]
      end.
  
  maybe_add_buckets_uuids(Config) ->
      case ns_config:search(Config, buckets) of
          {value, Buckets} ->
              Configs = proplists:get_value(configs, Buckets, []),
              NewConfigs = lists:map(fun maybe_add_bucket_uuid/1, Configs),
  
              case NewConfigs =:= Configs of
                  true ->
                      [];
                  false ->
                      NewBuckets = misc:update_proplist(Buckets,
                                                        [{configs, NewConfigs}]),
                      [{set, buckets, NewBuckets}]
              end;
          false ->
              []
      end.
  
  maybe_add_bucket_uuid({BucketName, BucketConfig} = Bucket) ->
      case proplists:get_value(uuid, BucketConfig) of
          undefined ->
              {BucketName, [{uuid, couch_uuids:random()} | BucketConfig]};
          _UUID ->
              Bucket
      end.
  
  -ifdef(EUNIT).
  
  add_vbucket_map_history_test() ->
  