private void receiveFencedInstanceIdException() {
        subscriptions.assignFromUser(singleton(t1p));

        client.prepareResponse(groupCoordinatorResponse(node, Errors.NONE));
        coordinator.ensureCoordinatorReady(time.timer(Long.MAX_VALUE));

        prepareOffsetCommitRequest(singletonMap(t1p, 100L), Errors.FENCED_INSTANCE_ID);

        coordinator.commitOffsetsAsync(singletonMap(t1p, new OffsetAndMetadata(100L)), new MockCommitCallback());
        assertEquals(coordinator.inFlightAsyncCommits.get(), 0);
        coordinator.invokeCompletedOffsetCommitCallbacks();
    }
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