ClusterSharding.Get(ActorSystem system) fails with TestKit ActorSystem

[newmancodes]

.net framework v4.6.1
Akka.Net v1.3.0
Akka.Cluster.Sharding v1.3.0-beta50
Akka.TestKit v1.3.0

Executing on Windows

TestKit is being created with this HOCON - via constructor on TestKit that accepts a Config object.

akka {
loglevel = INFO
actor {
serialize-creators = off
serialize-messages = on
serializers {
hyperion = "Akka.Serialization.HyperionSerializer, Akka.Serialization.Hyperion"
}
serialization-bindings {
"System.Object" = hyperion
}
serialization-settings {
hyperion {
version-tolerance = true
}
}
}
persistence {
snapshot-store {
plugin = "akka.persistence.no-snapshot-store"
}
}
}

When the call to ClusterSharding.Get(ActorSystem system) is performed a NullReferenceException is thrown with the following call stack.

System.NullReferenceException : Object reference not set to an instance of an object.
at Akka.Cluster.ClusterSettings..ctor(Config config, String systemName)
at Akka.Cluster.Cluster..ctor(ActorSystemImpl system)
at Akka.Cluster.ClusterExtension.CreateExtension(ExtendedActorSystem system)
at Akka.Actor.ExtensionIdProvider1.Akka.Actor.IExtensionId.CreateExtension(ExtendedActorSystem system) at Akka.Actor.Internal.ActorSystemImpl.<>c__DisplayClass56_0.<RegisterExtension>b__1() at System.Lazy1.CreateValue()
at System.Lazy1.LazyInitValue() at System.Lazy1.get_Value()
at Akka.Actor.Internal.ActorSystemImpl.TryGetExtension(Type extensionType, Object& extension)
at Akka.Actor.Internal.ActorSystemImpl.GetExtension(IExtensionId extensionId)
at Akka.Actor.ExtensionIdProvider1.Get(ActorSystem system) at Akka.Actor.ExtensionIdProvider1.Akka.Actor.IExtensionId.Get(ActorSystem system)
at Akka.Actor.Internal.ActorSystemImpl.RegisterExtension(IExtensionId extension)
at Akka.Actor.ActorSystemWithExtensions.WithExtension[T,TI](ActorSystem system)
at Akka.Cluster.Sharding.ClusterSharding..ctor(ExtendedActorSystem system)
at Akka.Cluster.Sharding.ClusterShardingExtensionProvider.CreateExtension(ExtendedActorSystem system)
at Akka.Actor.ExtensionIdProvider1.Akka.Actor.IExtensionId.CreateExtension(ExtendedActorSystem system) at Akka.Actor.Internal.ActorSystemImpl.<>c__DisplayClass56_0.<RegisterExtension>b__1() at System.Lazy1.CreateValue()
at System.Lazy1.LazyInitValue() at System.Lazy1.get_Value()
at Akka.Actor.Internal.ActorSystemImpl.TryGetExtension(Type extensionType, Object& extension)
at Akka.Actor.Internal.ActorSystemImpl.GetExtension(IExtensionId extensionId)
at Akka.Actor.ExtensionIdProvider1.Get(ActorSystem system) at Akka.Actor.ExtensionIdProvider1.Akka.Actor.IExtensionId.Get(ActorSystem system)
at Akka.Actor.Internal.ActorSystemImpl.RegisterExtension(IExtensionId extension)
at Akka.Actor.ActorSystemWithExtensions.WithExtension[T,TI](ActorSystem system)
at Akka.Cluster.Sharding.ClusterSharding.Get(ActorSystem system)

[Horusiath]

Have you used ClusterSharding.DefaultConfig() as a configuration fallback?

[newmancodes]

I just tried it, and receive the same issue, but thanks for the suggestion.

[newmancodes]

I've removed the fallback and updated my config to use the cluster actor ref provider and this seems to have cleaned up a lot of the issues.

provider = "Akka.Cluster.ClusterActorRefProvider, Akka.Cluster"

A nicer error message might be handy but it's a step forward.