refactor back to a switch

consumergroup.go

@@ -725,20 +725,24 @@ func (cg *ConsumerGroup) run() {
 		// joining or syncing the group.
 		var backoff <-chan time.Time
 
-		if err == nil {
+		switch {
+		case err == nil:
 			// no error...the previous generation finished normally.
 			continue
-		} else if errors.Is(err, ErrGroupClosed) {
+
+		case errors.Is(err, ErrGroupClosed):
 			// the CG has been closed...leave the group and exit loop.
 			_ = cg.leaveGroup(memberID)
 			return
-		} else if errors.Is(err, RebalanceInProgress) {
+
+		case errors.Is(err, RebalanceInProgress):
 			// in case of a RebalanceInProgress, don't leave the group or
 			// change the member ID, but report the error.  the next attempt
 			// to join the group will then be subject to the rebalance
 			// timeout, so the broker will be responsible for throttling
 			// this loop.
-		} else {
+
+		default:
 			// leave the group and report the error if we had gotten far
 			// enough so as to have a member ID.  also clear the member id
 			// so we don't attempt to use it again.  in order to avoid