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Author: rkannan82

service/history/tasks/utils.go

@@ -82,6 +82,7 @@ func GetTransferTaskEventID(
 		if len(task.ScheduledEventIDs) > 0 {
 			eventID = task.ScheduledEventIDs[0]
 		} else {
+			// Should never happen.
 			eventID = common.FirstEventID
 		}
 	case *FakeTask:

service/history/workflow/task_generator.go

@@ -590,6 +590,7 @@ func (r *TaskGeneratorImpl) GenerateCancelActivityNexusTasks(scheduledEventID in
 	}
 
 	ai, ok := r.mutableState.GetActivityInfo(scheduledEventID)
+	// If control queue is not set, it means the worker that this activity belongs to does not support Nexus tasks.
 	if !ok || ai.WorkerControlTaskQueue == "" {
 		return nil
 	}