Here’s an addition to Akka TestKit that might come in handy. It does what it says: you can give it a couple of messages that you’re expecting within a given duration (defaults to 3s). Unlike expectMsgAllOf from the TestKit it ignores other messages that get sent to the testActor (expectMsgAllOf fails the test in that case).

  import scala.collection.mutable
  def expectMsgAllOfIgnoreOthers[T](max: Duration, expected: T*) {
    val outstanding = mutable.Set(expected: _*)
    fishForMessage(max) {
      case msg: T if outstanding.contains(msg) ⇒
        outstanding.remove(msg)
        outstanding.isEmpty
      case _ ⇒ false
    }
  }

  def expectMsgAllOfIgnoreOthers[T](expected: T*) { 
    expectMsgAllOfIgnoreOthers(3 seconds, expected: _*) 
  }