AbstractPartialFunction.

Contributed by Todd Vierling with minor mods by extempore. This is an
obvious extension of AbstractFunctionN which I had some issue making
work at the time. Sounds kind of pitiful given that the compiler patch
is about two lines, but let's all agree to believe it was a different
world then.

This example program is impacted as follows:

    class A {
      def f: PartialFunction[Any, Int] = { case x: String => 1 }
      def g: PartialFunction[Any, Int] = f orElse { case x: List[_] => 2 }
      def h: PartialFunction[Any, Int] = g orElse { case x: Set[_] => 3 }
    }

Before: 34943 bytes of bytecode
 After:  4217 bytes of bytecode

A mere 88% reduction in size. "'Tis but a trifle!" Closes SI-5096,
SI-5097.

4 files changed, 4 insertions, 3 deletions

diff --git a/src/compiler/scala/tools/cmd/FromString.scala b/src/compiler/scala/tools/cmd/FromString.scala
index 3792c26c34..992530c767 100644
--- a/src/compiler/scala/tools/cmd/FromString.scala
+++ b/src/compiler/scala/tools/cmd/FromString.scala
@@ -14,7 +14,7 @@ import scala.reflect.OptManifest
  *  example instances are in the companion object, but in general
  *  either IntFromString will suffice or you'll want custom transformers.
  */
-abstract class FromString[+T](implicit m: OptManifest[T]) extends PartialFunction[String, T] {
+abstract class FromString[+T](implicit m: OptManifest[T]) extends scala.runtime.AbstractPartialFunction[String, T] {
   def apply(s: String): T
   def isDefinedAt(s: String): Boolean = true
   def zero: T = apply("")
diff --git a/src/compiler/scala/tools/nsc/interpreter/AbstractOrMissingHandler.scala b/src/compiler/scala/tools/nsc/interpreter/AbstractOrMissingHandler.scala
index 2f47685757..d21d67db6e 100644
--- a/src/compiler/scala/tools/nsc/interpreter/AbstractOrMissingHandler.scala
+++ b/src/compiler/scala/tools/nsc/interpreter/AbstractOrMissingHandler.scala
@@ -6,7 +6,7 @@
 package scala.tools.nsc
 package interpreter
 
-class AbstractOrMissingHandler[T](onError: String => Unit, value: T) extends PartialFunction[Throwable, T] {
+class AbstractOrMissingHandler[T](onError: String => Unit, value: T) extends scala.runtime.AbstractPartialFunction[Throwable, T] {
   def isDefinedAt(t: Throwable) = t match {
     case _: AbstractMethodError     => true
     case _: NoSuchMethodError       => true
diff --git a/src/compiler/scala/tools/nsc/matching/ParallelMatching.scala b/src/compiler/scala/tools/nsc/matching/ParallelMatching.scala
index 197839c7e0..b073bb3c96 100644
--- a/src/compiler/scala/tools/nsc/matching/ParallelMatching.scala
+++ b/src/compiler/scala/tools/nsc/matching/ParallelMatching.scala
@@ -422,7 +422,7 @@ trait ParallelMatching extends ast.TreeDSL
       // Should the given pattern join the expanded pivot in the success matrix? If so,
       // this partial function will be defined for the pattern, and the result of the apply
       // is the expanded sequence of new patterns.
-      lazy val successMatrixFn = new PartialFunction[Pattern, List[Pattern]] {
+      lazy val successMatrixFn = new scala.runtime.AbstractPartialFunction[Pattern, List[Pattern]] {
         private def seqIsDefinedAt(x: SequenceLikePattern) = (hasStar, x.hasStar) match {
           case (true, true)   => true
           case (true, false)  => pivotLen <= x.nonStarLength
diff --git a/src/compiler/scala/tools/nsc/transform/UnCurry.scala b/src/compiler/scala/tools/nsc/transform/UnCurry.scala
index 864939ebfd..b15f73887a 100644
--- a/src/compiler/scala/tools/nsc/transform/UnCurry.scala
+++ b/src/compiler/scala/tools/nsc/transform/UnCurry.scala
@@ -247,6 +247,7 @@ abstract class UnCurry extends InfoTransform
         val anonClass = owner newAnonymousFunctionClass fun.pos setFlag (FINAL | SYNTHETIC | inConstructorFlag)
         def parents =
           if (isFunctionType(fun.tpe)) List(abstractFunctionForFunctionType(fun.tpe), SerializableClass.tpe)
+          else if (isPartial) List(appliedType(AbstractPartialFunctionClass.typeConstructor, targs), SerializableClass.tpe)
           else List(ObjectClass.tpe, fun.tpe, SerializableClass.tpe)
 
         anonClass setInfo ClassInfoType(parents, new Scope, anonClass)