Reflection: cannot invoke a method that takes a value class parameter

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scala> class X[T](val i: T) extends AnyVal
defined class X

scala> object a { def y[T](x: X[T]) = x.i }
defined module a

scala> val cm = reflect.runtime.currentMirror
cm: reflect.runtime.universe.Mirror = JavaMirror with scala.tools.nsc.interpreter.IMain$TranslatingClassLoader@4bcc946b of type class scala.tools.nsc.interpreter.IMain$TranslatingClassLoader with classpath [(memory)] and parent being scala.tools.nsc.util.ScalaClassLoader$URLClassLoader@642423ad of type class scala.tools.nsc.util.ScalaClassLoader$URLClassLoader with classpath [file:/Library/Java/JavaVirtualMachines/1.6.0_27-b07-395.jdk/Contents/Classes/classes.jar,file:/Library/Java/JavaVirtualMachines/1.6.0_27-b07-395.jdk/Contents/Classes/ui.jar,file:/Library/Java/JavaVirtualMachines/1.6.0_27-b07-395.jdk/Contents/Classes/jsse.jar,file:/Library/Java/JavaVirtualMachines/1.6.0_27-b07-395.jdk/Contents/Classes/jce.jar,file:/Library/Java/JavaVirtualMachines/1.6.0_27-b07-395.jdk/Contents/Class...
scala> val moduleA = cm.reflect(a)
moduleA: reflect.runtime.universe.InstanceMirror = instance mirror for a$@6ff64801

scala> val methodY = moduleA.symbol.typeSignature.declarations.last.asMethod
methodY: reflect.runtime.universe.MethodSymbol = method y

scala> moduleA.reflectMethod(methodY)
res10: reflect.runtime.universe.MethodMirror = method mirror for a.y[T](x: X[T]): T (bound to a$@6ff64801)

scala> res10(new X(0))
java.lang.NoClassDefFoundError: no Java class corresponding to ErasedValueType(X[T]) found
	at scala.reflect.runtime.JavaMirrors$JavaMirror.typeToJavaClass(JavaMirrors.scala:1160)

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Imported From: https://issues.scala-lang.org/browse/SI-6411?orig=1
Reporter: @retronym
Affected Versions: 2.10.0
See #6336

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@retronym said:
Residuals from #6336

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@paulp said:
Here it is in a more test-casey form.

class X[T](val i: T) extends AnyVal

object a {
  def y[T](x: X[T]) = x.i
}

object Test {
  def main(args: Array[String]) {
    val cm      = scala.reflect.runtime.currentMirror
    val moduleA = cm.reflect(a)
    val methodY = moduleA.symbol.typeSignature.declarations.last.asMethod
    val m       = moduleA.reflectMethod(methodY)

    m(new X(0))
    // java.lang.NoClassDefFoundError: no Java class corresponding to ErasedValueType(X[T]) found
    //   at scala.reflect.runtime.JavaMirrors$JavaMirror.typeToJavaClass(JavaMirrors.scala:1225)
    //   at scala.reflect.runtime.JavaMirrors$JavaMirror$$anonfun$methodToJava$1$$anonfun$27.apply(JavaMirrors.scala:1192)
    //   at scala.reflect.runtime.JavaMirrors$JavaMirror$$anonfun$methodToJava$1$$anonfun$27.apply(JavaMirrors.scala:1192)
  }
}

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@xeno-by said:
That's not related to value classes as a language feature, but rather to the reflection runtime.

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@adriaanm said:
(Pushing reflection bugs to 2.11 to aid scheduling -- as it's experimental in 2.10.x, it shouldn't influence 2.10's schedule. They may be fixed earlier, of course.)

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@xeno-by said:
scala/scala#2041

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@xeno-by said:
(That's just a random bug that I fixed to bring my number of open pull requests to 10. Feel free to demote it back to 2.11.0 if necessary)

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@xeno-by said (edited on Feb 4, 2013 10:26:52 PM UTC):
Don't have time for this in 2.10.1. The pull request has almost got through the review, though.

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@xeno-by said:
scala/scala#3409