Compiler option -Vtype-diffs leads to error type information lost in some case. #12561
Description
Reproduction steps
Scala version: 2.13.8
The build.sbt
ThisBuild / version := "0.1.0"
ThisBuild / scalaVersion := "2.13.8"
lazy val root = (project in file("."))
.settings(
name := "demo"
)
.aggregate(
project1
)
lazy val project1 =
(project in file("project1"))
.settings(
commonSettings("project1"),
libraryDependencies += "com.typesafe.akka" %% "akka-actor" % "2.5.32"
)
def commonSettings(module: String, languageVersion: String = "2.13.8") = {
Seq[Setting[_]](
name := s"demo-$module",
scalaVersion := languageVersion,
scalacOptions ++= Seq(
"-Vtype-diffs",
),
fork := true
)
}The 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"))
}
}Problem
When compile above code, the type information is lost in error.
BugExample.scala:11:56: type mismatch;
[error] () => scala.Unit
[error] system.scheduler.schedule(1.second, 10.seconds, () => println("why cant convert this to Runnable"))
[error] ^
[error] one error found
[error] (project1 / Compile / compileIncremental) Compilation failed
It should be
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"))
see also #12560