+ // Now send the LeaderTransitioning to follower2 after it has received AppendEntries from the new leader.
+ follower2Actor.tell(leaderTransitioning, ActorRef.noSender());
+
+ verifyLeaderStateChangedMessages(leaderNotifierActor, null, follower1Id);
+ verifyLeaderStateChangedMessages(follower1NotifierActor, null, follower1Id);
+ // follower2 should only get 1 LeaderStateChanged with the new leaderId - the LeaderTransitioning message
+ // should not generate a LeaderStateChanged with null leaderId since it arrived after the new leaderId was set.
+ verifyLeaderStateChangedMessages(follower2NotifierActor, follower1Id);
+ verifyLeaderStateChangedMessages(follower3NotifierActor, null, follower1Id);
+