Failing persistence test when one probe is used.

Failing_Test.scala

package akka.persistence

import com.typesafe.config._

import scala.concurrent.duration._

import akka.actor._
import akka.persistence._

import akka.testkit._

case class SetNumber(number: Int)
case class Add(number: Int)
case class Subtract(number: Int)
case object DecrementAndGet
case object GetNumber

class NumberProcessor(name: String) extends NamedProcessor(name) {
  override def processorId = name

  var num = 0

  def receive = {
    case Persistent(SetNumber(number), _) ⇒ num = number
    case Persistent(Add(number), _)       ⇒ num = num + number
    case Persistent(Subtract(number), _)  ⇒ num = num - number
    case GetNumber                        ⇒ sender ! num
    case p @ Persistent(DecrementAndGet, _) ⇒
      num = num - 1
      sender ! num
    case DecrementAndGet ⇒
      num = num - 1
      sender ! num
  }
}

abstract class NumberProcessorSpec(config: Config) extends AkkaSpec(config)
  with PersistenceSpec {

  "A processor" must {
    "this works" in {
      val probe = TestProbe()
      val processor = namedProcessor[NumberProcessor]
      processor.tell(GetNumber, probe.testActor)
      probe.expectMsg(0)
      processor.tell(Persistent(DecrementAndGet), probe.testActor)
      probe.expectMsg(-1)

      watch(processor)
      system.stop(processor)
      expectMsgType[Terminated]

      val processorResurrected = namedProcessor[NumberProcessor]

      val anotherProbe = TestProbe()
      processorResurrected.tell(Persistent(DecrementAndGet), anotherProbe.testActor)

      anotherProbe.expectMsg(-2)
    }

    "this doesn't, why?" in {
      val probe = TestProbe()
      val processor = namedProcessor[NumberProcessor]
      processor.tell(GetNumber, probe.testActor)
      probe.expectMsg(0)
      processor.tell(Persistent(DecrementAndGet), probe.testActor)
      probe.expectMsg(-1)

      watch(processor)
      system.stop(processor)
      expectMsgType[Terminated]

      val processorResurrected = namedProcessor[NumberProcessor]
      processorResurrected.tell(Persistent(DecrementAndGet), probe.testActor)

      probe.expectMsg(-2)
    }
  }
}

class NumberSpec extends NumberProcessorSpec(PersistenceSpec.config("leveldb", "NumberSpec"))