Runtime error when calling a java-defined method whose signature contains value classes #9298
Description
It looks like scalac tries to semi-erase value classes in Java-defined symbols, which of course doesn't make sense since these symbols come from a classfile:
Meter.scala:
class Meter(val x: Int) extends AnyValJUse.java:
class JUse {
public static Meter jm() {
return new Meter(2);
}
}Use.scala:
object Use {
def main(args: Array[String]): Unit = {
val x: Meter = JUse.jm
}
}Runtime error:
% scala Use
java.lang.NoSuchMethodError: JUse.jm()I
at Use$.main(Use.scala:5)
at Use.main(Use.scala)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:497)
at scala.reflect.internal.util.ScalaClassLoader$$anonfun$run$1.apply(ScalaClassLoader.scala:70)
at scala.reflect.internal.util.ScalaClassLoader$class.asContext(ScalaClassLoader.scala:31)
at scala.reflect.internal.util.ScalaClassLoader$URLClassLoader.asContext(ScalaClassLoader.scala:101)
at scala.reflect.internal.util.ScalaClassLoader$class.run(ScalaClassLoader.scala:70)
at scala.reflect.internal.util.ScalaClassLoader$URLClassLoader.run(ScalaClassLoader.scala:101)
at scala.tools.nsc.CommonRunner$class.run(ObjectRunner.scala:22)
at scala.tools.nsc.ObjectRunner$.run(ObjectRunner.scala:39)
at scala.tools.nsc.CommonRunner$class.runAndCatch(ObjectRunner.scala:29)
at scala.tools.nsc.ObjectRunner$.runAndCatch(ObjectRunner.scala:39)
at scala.tools.nsc.MainGenericRunner.runTarget$1(MainGenericRunner.scala:65)
at scala.tools.nsc.MainGenericRunner.run$1(MainGenericRunner.scala:87)
at scala.tools.nsc.MainGenericRunner.process(MainGenericRunner.scala:98)
at scala.tools.nsc.MainGenericRunner$.main(MainGenericRunner.scala:103)
at scala.tools.nsc.MainGenericRunner.main(MainGenericRunner.scala)The output of Erasure confirms that the compiler has completely lost its mind as it tries to cast an Integer to a Meter:
object Use extends Object {
def <init>(): Use.type = {
Use.super.<init>();
()
};
def main(args: Array[String]): Unit = {
val x: ErasedValueType(class Meter, Int) = scala.Int.box(JUse.jm()).$asInstanceOf[Meter]().x().$asInstanceOf[ErasedValueType(class Meter, Int)]();
()
}
}