SAM convert not work in overloaded method parameter. #12560
Description
Reproduction steps
Scala Version: 2.13.8
I cant reproduce it by raw scala, it's only reproduce in akka function.
I'm not sure if the bug is also related to akka.
Add akka library in sbt
libraryDependencies += "com.typesafe.akka" %% "akka-actor" % "2.5.32"And then compile following code
import akka.actor.ActorSystem
import scala.concurrent.duration._
object BugExample {
def main(args: Array[String]): Unit = {
val system = ActorSystem("test")
implicit val ec = system.dispatcher
system.scheduler.schedule(1.second, 10.seconds, () => println("why cant convert this to Runnable"))
}
}
And here is the schedule method
def schedule(initialDelay: FiniteDuration, interval: FiniteDuration, runnable: Runnable)(
implicit executor: ExecutionContext): CancellableCompile failed with error
BugExample.scala:11:56: type mismatch;
[error] found : () => Unit
[error] required: Runnable
[error] system.scheduler.schedule(1.second, 10.seconds, () => println("why cant convert this to Runnable"))
Problem
Following code works well
import akka.actor.ActorSystem
import scala.concurrent.ExecutionContext
import scala.concurrent.duration._
object BugExample {
// self defined function works well
def test1() = {
def schedule(initialDelay: FiniteDuration, interval: FiniteDuration, runnable: Runnable)(
implicit executor: ExecutionContext): Unit = {
println(s"$initialDelay $interval")
runnable.run()
}
val system = ActorSystem("test")
implicit val ec = system.dispatcher
schedule(1.second, 10.seconds, () => println("works well 1"))
}
// declare type explicitly works well
def test2() = {
val system = ActorSystem("test")
implicit val ec = system.dispatcher
val f: Runnable = () => println("works well 2")
system.scheduler.schedule(1.second, 10.seconds, f)
}
def main(args: Array[String]): Unit = {
test1()
test2()
}
}IMO, the compiler should convert () => scala.Unit to Runnable .
What's the problem here ?
Environment:
sbt: 1.6.2
jdk: corretto 17, openjdk 11