anchor.diff:    ?ESCALATE_EC(JoinRsp#kpro_JoinGroupResponse.errorCode),
     #kpro_JoinGroupResponse
       { generationId          = GenerationId
  -    , protocolName          = PaStrategy
  +    , protocolName          = _PaStrategyBinStr
       , leaderId              = LeaderId
       , memberId              = MemberId
       , groupMemberMetadata_L = Members
  
positive.code:       },
    ConsumerGroupProtocol =
      #kpro_GroupProtocol
        { protocolName     = PaStrategy
        , protocolMetadata = ConsumerGroupProtocolMeta
        },
    SessionTimeout = timer:seconds(SessionTimeoutSec),
  
negative.code: -spec do_assign_partitions(partition_assignment_strategy(),
                             [kpro_GroupMemberMetadata()],
                             [{topic(), partition()}]) -> [member_assignment()].
  do_assign_partitions(roundrobin, Members, AllPartitions) ->
    %% round robin, we only care about the member id
    F = fun(#kpro_GroupMemberMetadata{memberId = MemberId}) -> MemberId end,
    MemberIds = lists:map(F, Members),
  