Request message with 2 parameters doesn't compile with ctx.ask (Scala 2.13)

[patriknw]

The following doesn't compile with Scala 2.13.0-M5 (works with 2.12.8) in ClusterShardingSpec:

      Behaviors.setup[TheReply] { ctx =>
	        ctx.ask(aliceRef)(WhoAreYou2(17, _)) {
	          case Success(name) => TheReply(name)
	          case Failure(ex)   => TheReply(ex.getMessage)
	        }
	
	        Behaviors.empty
	      }

[error] /home/travis/build/akka/akka/akka-cluster-sharding-typed/src/test/scala/akka/cluster/sharding/typed/scaladsl/ClusterShardingSpec.scala:358:42: missing parameter type for expanded function ((x$6: <error>) => WhoAreYou2(17, x$6))
[error]         ctx.ask(aliceRef)(WhoAreYou2(17, _)) {
[error]                                          ^
[error] /home/travis/build/akka/akka/akka-cluster-sharding-typed/src/test/scala/akka/cluster/sharding/typed/scaladsl/ClusterShardingSpec.scala:359:42: type mismatch;
[error]  found   : Any
[error]  required: String
[error]           case Success(name) => TheReply(name)
[error]     

[patriknw]

@johanandren similar to the other ask issue you investigated?

[johanandren]

Yes, similar indeed. That is strange if it does not compile on 2.13 because we have one that is very similar test coverage in https://github.com/akka/akka/blob/master/akka-actor-typed-tests/src/test/scala/akka/actor/typed/scaladsl/ActorContextAskSpec.scala#L88 that seems to compile fine.

[patriknw]

but that one doesn't have two parameters?

[patriknw]

The signature is here: https://github.com/akka/akka/blob/76492649987baa9838674bc91b1b4bb48d9779db/akka-actor-typed/src/main/scala/akka/actor/typed/scaladsl/ActorContext.scala#L290-L291

[patriknw]

Note that it works with single parameter:

        ctx.ask(aliceRef)(WhoAreYou) {
          case Success(name) => TheReply(name)
          case Failure(ex)   => TheReply(ex.getMessage)
        }

  final case class WhoAreYou(replyTo: ActorRef[String]) extends TestProtocol
  final case class WhoAreYou2(x: Int, replyTo: ActorRef[String]) extends TestProtocol

[adriaanm]

Ah hehe, this is also fixed in RC1. scala/scala#7340 backported the relevant fixes to 2.12.8 between M5 and RC1.

[patriknw]

Great, thanks for looking into it.

[patriknw]

Leaving this ticket open until we have switched to RC1 and then we should include that example in ClusterShardingSpec