refactor GPA: typed messages

[dessaya]

No description provided.

[chriscandless]

How do you feel about these inline msgs.AddAll(doSometing), slices.Concat(msgs, stateMgr.Input(...)) etc?
Would you agree, that this style is very common in this code and that it decreases readbility? How about changing it to something like this:

res := cmi.suspendCommittee(cmi.latestActiveCommittee)
outmsgs = slices.Concat(msgs, resOutMsgs)

Because I personally loose focus when reading code like: msgs.AddAll(stateMgr.Input(NewInputThingyDone(inputArg))) :D

[dessaya]

Personally I don't find it so distracting, but I'm also not against splitting those lines if it improves readability! Let's do it.

[chriscandless]

I would split that into 3-4 lines :D

[chriscandless]

Would you like MessageInT more?

[dessaya]

I don't like either 😝

[chriscandless]

While I do see benefit of what you did here, I also see, that TypedMessageIn[SomePayload] is not automatically convertiable to MessageIn. When it was interface it was convertible.
Didn't this aspect create you any problem while refacroting? Because if not - maybe not is not a real drawback.

[dessaya]

Yes, this is why I added the AsTypedMessageIn function, e.g.:

func (cmi *ChainMgr) Message(msg *gpa.MessageIn) []*gpa.MessageOut {
	switch msg.Payload.(type) {
	case *msgCommitteeLog:
		return cmi.handleMsgCommitteeLog(gpa.AsTypedMessageIn[*msgCommitteeLog](msg))
	case *msgBlockProduced:
		return cmi.handleMsgBlockProduced(gpa.AsTypedMessageIn[*msgBlockProduced](msg))
	}
	panic(fmt.Errorf("unexpected message %T: %+v", msg, msg))
}

I'm not too happy with the ergonomics. If only Go had better type inference :(