@Override
            public void onPartitionsAssigned(Collection<TopicPartition> partitions) {
                boolean raiseWakeup = this.assignedCount == 0;
                super.onPartitionsAssigned(partitions);

                if (raiseWakeup)
                    throw new WakeupException();
            }
Verifies that subscription change updates SubscriptionState correctly even after JoinGroup failures
that don't re-invoke onJoinPrepare.
clients/src/test/java/org/apache/kafka/clients/consumer/internals/ConsumerCoordinatorTest.java