anchor.diff:                    {set, {node, _, memcached_config}, _}],
                    do_upgrade_config_from_2_3_0_to_3_0(Cfg, Default)).
   
  +upgrade_3_0_to_3_0_1_test() ->
  +    Cfg = [[{some_key, some_value},
  +            {{node, node(), memcached},
  +             [{engines, old_value},
  +              {ssl_port, 1},
  +              {verbosity, 2},
  +              {port, 3}]},
  +            {{node, node(), memcached_config}, memcached_config}]],
  +    Default = [{{node, node(), port_servers}, port_servers_cfg},
  +               {{node, node(), memcached}, [{ssl_port, 1}, {verbosity, 3},
  +                                            {engines, [something]}]},
  +               {{node, node(), memcached_config}, memcached_config}],
  +
  +    ?assertMatch([{set, {node, _, memcached}, [{engines, [something]},
  +                                               {ssl_port, 1}, {verbosity, 2},
  +                                               {port, 3}]}],
  +                 do_upgrade_config_from_3_0_to_3_0_1(Cfg, Default)).
  +
  +
   no_upgrade_on_current_version_test() ->
       ?assertEqual([], upgrade_config([[{{node, node(), config_version}, get_current_version()}]])).
   
  
positive.code:              upgrade_config_from_2_2_0_to_2_3_0(Config)];
          {value, {2,3,0}} ->
              [{set, {node, node(), config_version}, {3,0}} |
               upgrade_config_from_2_3_0_to_3_0(Config)]
      end.
  
  upgrade_config_from_1_7_to_1_7_1() ->
  
negative.code: -define(NS_LOG, "ns_log").
  
  get_current_version() ->
      {3,0,1}.
  
  ensure_data_dir() ->
      RawDir = path_config:component_path(data),
  