private static ClusterHeartbeatSenderState EmptyState(UniqueAddress selfUniqueAddress) { return new ClusterHeartbeatSenderState(new HeartbeatNodeRing(selfUniqueAddress, new[] { selfUniqueAddress }, 3), ImmutableHashSet.Create<UniqueAddress>(), new DefaultFailureDetectorRegistry<Address>(() => new FailureDetectorStub())); }