anchor.diff:      ?assertMatch(ok, W:call(Res, update, [Id1, D3, M3])),
   
       %% 出席
  -    W:reg_server(Yifan, [{ss_account, [#{db=>Db}]}]),
  +    W:reg_server(Yifan, ss_account, [#{db=>Db}]),
       W:call(Yifan, connect, self()),
       ?assertMatch(not_login, W:call(Yifan, contacts)),
       ?assertMatch(ok, W:call(Yifan, login, ["yifan", "123456"])),
  
positive.code:     Xiaojie = {account, "xiaojie"},
      D8 = #{account => "xiaojie", password => "123456"},
      ?assertMatch({ok, _}, W:call(Res, create, [D8, M1])),
      W:reg_server(Xiaojie, [{ss_account, [#{db=>Db}]}]),
      W:call(Xiaojie, connect, [self()]),
      ?assertMatch(ok, W:call(Xiaojie, login, ["xiaojie", "123456"])),
      clear_msg(),
  
negative.code:     D2 = #{account => "adi", password => "123456", contacts => [{"yifan", #{rel=>double}}]},
      {ok, Id2} = W:call(Res, create, [D2, M2]),
      W:call(Res, find, [Id2]),
      W:reg_server(Adi, ss_account, [#{db=>Db}]),
      W:call(Adi, connect, self()),
      ?assertMatch(not_login, W:call(Adi, status, [])),
      ?assertMatch(ok, W:call(Adi, login, ["adi", "123456"])),
  