Matchmaker not working when minimum is greater or equal to 4

Local Setup
1

I’m using
Nakama version : 3.1.1

When I add match maker with minimum less or equal to 3 it work but if above 3 it doesn’t work. I check the code of matchmaker.go of nakama, I see the code doesn’t actually modify actual array. Check out below block of code from matchmaker.go and some comments.

entryCombos := make([][]*MatchmakerEntry, 0, 5) // <----- Not array of array pointer

for _, hit := range result.Hits {
...
var foundCombo []*MatchmakerEntry
for _, entryCombo := range entryCombos {     // <----- entryCombo is copied out
   if len(entryCombo)+len(entries)+index.Count <= index.MaxCount {

   		for _, entry := range entryCombo {
   			if _, found := hitIndex.SessionIDs[entry.Presence.SessionId]; found {
   				sessionIdConflict = true
   				break
   			}
   		}
   		if sessionIdConflict {
   			continue
   		}

   		entryCombo = append(entryCombo, entries...) <----- then modify the copied, not the actual array
   		foundCombo = entryCombo
   		break
   
   	}
....
}

I have solved this by modifying the entryCombos variable and let the loop access it as pointer accordingly.

entryCombos := make([][]*MatchmakerEntry, 0, 5)
// to
entryCombos := make([]*[]*MatchmakerEntry, 0, 5)
				  //  ^ Add this
2

@chounry Thanks for the detailed investigation. I see you’ve opened an issue and a pull request which we can use to carry on the discussion about the change. I don’t think your solution is quite right but we can discuss it further there. :+1:

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