anchor.diff:                                          {ok, Credential};
                                       <<"error">> ->
                                           {error, ErrMsg};
  +                                    <<"other_service">> ->
  +                                        {oidc_login, #{provider => <<"ID1">>,
  +                                                       msg => <<"Requires login">>}};
  +                                    <<"yet_another_service">> ->
  +                                        {oidc_login, #{provider => <<"ID2">>,
  +                                                       msg => <<"Requires login">>}};
                                       _ ->
                                           {error, internal}
                                   end
  
positive.code:     try
          ?assertEqual(true, watts:does_credential_exist(<<"id">>, Session)),
          ?assertEqual(true, watts:does_temp_cred_exist(<<"id">>, Session)),
          {ok, [#{id := <<"id">>}]} = watts:get_openid_provider_list(),
          ?assertEqual({ok, []}, watts:get_service_list_for(Session)),
          ?assertEqual({ok, []}, watts:get_credential_list_for(Session)),
          ?assertEqual({ok, <<"accesstoken">>}, watts:get_access_token_for(Session)),
  
negative.code:     {ok, {Session, _} = Meck} = start_meck(),
      try
          {ok, _} = watts:request_credential_for(<<"service">>, Session, []),
          {error, _} = watts:request_credential_for(<<"other_service">>, Session, []),
          {ok, #{result := oidc_login}} = watts:request_credential_for(
                                            <<"yet_another_service">>, Session, []),
          {error, _} = watts:request_credential_for(<<"error">>, Session, []),
          {error, _} = watts:request_credential_for(<<"bad">>, Session, [])
      after
  