[Scala 2.11.1] Multiple `isDefinedAt` generated by compiler when using tagged types

[amsayk]

test.scala

-------------

object main {

  type Tagged[T] = { type Tag = T }

  type @@[+T, Tag] = T with Tagged[Tag]

  def d() : PartialFunction[Int @@ Float, Any] = {case _ =>}

  def main(args: Array[String]):Unit = {

    d()

  }

}

scala> :load test.scala

Loading test.scala...

defined object main

scala> main.main(Array())

java.lang.ClassFormatError: Duplicate method name&signature in class file main$$anonfun$d$1

  at java.lang.ClassLoader.defineClass1(Native Method)

  at java.lang.ClassLoader.defineClass(ClassLoader.java:760)

  at scala.reflect.internal.util.AbstractFileClassLoader.findClass(AbstractFileClassLoader.scala:87)

  at java.lang.ClassLoader.loadClass(ClassLoader.java:424)

  at java.lang.ClassLoader.loadClass(ClassLoader.java:357)

  at main$.d(<console>:13)

  at main$.main(<console>:17)

  ... 32 elided

scala> main.main(Array())

java.lang.ClassFormatError: Duplicate method name&signature in class file main$$anonfun$d$1

  at java.lang.ClassLoader.defineClass1(Native Method)

  at java.lang.ClassLoader.defineClass(ClassLoader.java:760)

  at scala.reflect.internal.util.AbstractFileClassLoader.findClass(AbstractFileClassLoader.scala:87)

  at java.lang.ClassLoader.loadClass(ClassLoader.java:424)

  at java.lang.ClassLoader.loadClass(ClassLoader.java:357)

  at main$.d(<console>:13)

  at main$.main(<console>:17)

  ... 32 elided

scala> :javap main$$anonfun$d$1

  Size 1361 bytes

  MD5 checksum c7a82ba8510bdc92cbce7467751a7abb

  Compiled from "test.scala"

public final class main$$anonfun$d$1 extends scala.runtime.AbstractPartialFunction<java.lang.Object, java.lang.Object> implements scala.Serializable

  Signature: #3                           // Lscala/runtime/AbstractPartialFunction<Ljava/lang/Object;Ljava/lang/Object;>;Lscala/Serializable;

  SourceFile: "test.scala"

  EnclosingMethod: #10.#13                // main$.d

  InnerClasses:

       public static final #2; //class main$$anonfun$d$1

Error: unknown attribute

    Scala: length = 0x0

     

  minor version: 0

  major version: 50

  flags: ACC_PUBLIC, ACC_FINAL, ACC_SUPER

Constant pool:

   #1 = Utf8               main$$anonfun$d$1

   #2 = Class              #1             //  main$$anonfun$d$1

   #3 = Utf8               Lscala/runtime/AbstractPartialFunction<Ljava/lang/Object;Ljava/lang/Object;>;Lscala/Serializable;

   #4 = Utf8               scala/runtime/AbstractPartialFunction

   #5 = Class              #4             //  scala/runtime/AbstractPartialFunction

   #6 = Utf8               scala/Serializable

   #7 = Class              #6             //  scala/Serializable

   #8 = Utf8               test.scala

   #9 = Utf8               main$

  #10 = Class              #9             //  main$

  #11 = Utf8               d

  #12 = Utf8               ()Lscala/PartialFunction;

  #13 = NameAndType        #11:#12        //  d:()Lscala/PartialFunction;

  #14 = Utf8               applyOrElse

  #15 = Utf8               (Ljava/lang/Object;Lscala/Function1;)Ljava/lang/Object;

  #16 = Utf8               scala/runtime/BoxesRunTime

  #17 = Class              #16            //  scala/runtime/BoxesRunTime

  #18 = Utf8               unboxToInt

  #19 = Utf8               (Ljava/lang/Object;)I

  #20 = NameAndType        #18:#19        //  unboxToInt:(Ljava/lang/Object;)I

  #21 = Methodref          #17.#20        //  scala/runtime/BoxesRunTime.unboxToInt:(Ljava/lang/Object;)I

  #22 = Utf8               scala/runtime/BoxedUnit

  #23 = Class              #22            //  scala/runtime/BoxedUnit

  #24 = Utf8               UNIT

  #25 = Utf8               Lscala/runtime/BoxedUnit;

  #26 = NameAndType        #24:#25        //  UNIT:Lscala/runtime/BoxedUnit;

  #27 = Fieldref           #23.#26        //  scala/runtime/BoxedUnit.UNIT:Lscala/runtime/BoxedUnit;

  #28 = Utf8               this

  #29 = Utf8               Lmain$$anonfun$d$1;

  #30 = Utf8               x1

  #31 = Utf8               Ljava/lang/Object;

  #32 = Utf8               default

  #33 = Utf8               Lscala/Function1;

  #34 = Utf8               isDefinedAt

  #35 = Utf8               (I)Z

  #36 = Utf8               I

  #37 = Utf8               (Ljava/lang/Object;)Z

  #38 = NameAndType        #34:#35        //  isDefinedAt:(I)Z

  #39 = Methodref          #2.#38         //  main$$anonfun$d$1.isDefinedAt:(I)Z

  #40 = Utf8               x

  #41 = Utf8               (ILscala/Function1;)Ljava/lang/Object;

  #42 = NameAndType        #14:#41        //  applyOrElse:(ILscala/Function1;)Ljava/lang/Object;

  #43 = Methodref          #2.#42         //  main$$anonfun$d$1.applyOrElse:(ILscala/Function1;)Ljava/lang/Object;

  #44 = Utf8               <init>

  #45 = Utf8               ()V

  #46 = NameAndType        #44:#45        //  "<init>":()V

  #47 = Methodref          #5.#46         //  scala/runtime/AbstractPartialFunction."<init>":()V

  #48 = Utf8               Code

  #49 = Utf8               LocalVariableTable

  #50 = Utf8               LineNumberTable

  #51 = Utf8               Signature

  #52 = Utf8               <A1:Ljava/lang/Object;B1:Ljava/lang/Object;>(TA1;Lscala/Function1<TA1;TB1;>;)TB1;

  #53 = Utf8               SourceFile

  #54 = Utf8               EnclosingMethod

  #55 = Utf8               InnerClasses

  #56 = Utf8               Scala

{

  public final <A1 extends java.lang.Object, B1 extends java.lang.Object> B1 applyOrElse(A1, scala.Function1<A1, B1>);

    descriptor: (Ljava/lang/Object;Lscala/Function1;)Ljava/lang/Object;

    flags: ACC_PUBLIC, ACC_FINAL

    Code:

      stack=1, locals=5, args_size=3

         0: aload_1       

         1: invokestatic  #21                 // Method scala/runtime/BoxesRunTime.unboxToInt:(Ljava/lang/Object;)I

         4: istore_3      

         5: getstatic     #27                 // Field scala/runtime/BoxedUnit.UNIT:Lscala/runtime/BoxedUnit;

         8: astore        4

        10: aload         4

        12: areturn       

      LocalVariableTable:

        Start  Length  Slot  Name   Signature

            0      13     0  this   Lmain$$anonfun$d$1;

            0      13     1    x1   Ljava/lang/Object;

            0      13     2 default   Lscala/Function1;

      LineNumberTable:

        line 8: 0

    Signature: #52                          // <A1:Ljava/lang/Object;B1:Ljava/lang/Object;>(TA1;Lscala/Function1<TA1;TB1;>;)TB1;

  public final boolean isDefinedAt(int);

    descriptor: (I)Z

    flags: ACC_PUBLIC, ACC_FINAL

    Code:

      stack=1, locals=4, args_size=2

         0: iload_1       

         1: istore_2      

         2: iconst_1      

         3: istore_3      

         4: iload_3       

         5: ireturn       

      LocalVariableTable:

        Start  Length  Slot  Name   Signature

            0       6     0  this   Lmain$$anonfun$d$1;

            0       6     1    x1   I

      LineNumberTable:

        line 8: 0

  public final boolean isDefinedAt(java.lang.Object);

    descriptor: (Ljava/lang/Object;)Z

    flags: ACC_PUBLIC, ACC_FINAL, ACC_BRIDGE, ACC_SYNTHETIC

    Code:

      stack=2, locals=2, args_size=2

         0: aload_0       

         1: aload_1       

         2: invokestatic  #21                 // Method scala/runtime/BoxesRunTime.unboxToInt:(Ljava/lang/Object;)I

         5: invokevirtual #39                 // Method isDefinedAt:(I)Z

         8: ireturn       

      LocalVariableTable:

        Start  Length  Slot  Name   Signature

            0       9     0  this   Lmain$$anonfun$d$1;

            0       9     1     x   Ljava/lang/Object;

      LineNumberTable:

        line 8: 0

  public final java.lang.Object applyOrElse(java.lang.Object, scala.Function1);

    descriptor: (Ljava/lang/Object;Lscala/Function1;)Ljava/lang/Object;

    flags: ACC_PUBLIC, ACC_FINAL, ACC_BRIDGE, ACC_SYNTHETIC

    Code:

      stack=3, locals=3, args_size=3

         0: aload_0       

         1: aload_1       

         2: invokestatic  #21                 // Method scala/runtime/BoxesRunTime.unboxToInt:(Ljava/lang/Object;)I

         5: aload_2       

         6: invokevirtual #43                 // Method applyOrElse:(ILscala/Function1;)Ljava/lang/Object;

         9: areturn       

      LocalVariableTable:

        Start  Length  Slot  Name   Signature

            0      10     0  this   Lmain$$anonfun$d$1;

            0      10     1     x   Ljava/lang/Object;

            0      10     2 default   Lscala/Function1;

      LineNumberTable:

        line 8: 0

  public main$$anonfun$d$1();

    descriptor: ()V

    flags: ACC_PUBLIC

    Code:

      stack=1, locals=1, args_size=1

         0: aload_0       

         1: invokespecial #47                 // Method scala/runtime/AbstractPartialFunction."<init>":()V

         4: return        

      LocalVariableTable:

        Start  Length  Slot  Name   Signature

            0       5     0  this   Lmain$$anonfun$d$1;

      LineNumberTable:

        line 8: 0

}

Is this expected behavior; Any workarounds

[Simon Ochsenreither]

It seems like applyOrElse is causing the issue, not isDefinedAt, but this surely isn't supposed to happen.