[vpm] generate proper isDefinedAt for switches

don't consider the matcherror-throwing catch-all case (generated by virtpatmat) a default case

3 files changed, 35 insertions, 3 deletions

diff --git a/src/compiler/scala/tools/nsc/transform/UnCurry.scala b/src/compiler/scala/tools/nsc/transform/UnCurry.scala
index c26b19b04d..94e562b82f 100644
--- a/src/compiler/scala/tools/nsc/transform/UnCurry.scala
+++ b/src/compiler/scala/tools/nsc/transform/UnCurry.scala
@@ -348,11 +348,18 @@ abstract class UnCurry extends InfoTransform
             substTree(idaBlock.duplicate) // duplicate on block as a whole to ensure valdefs are properly cloned and substed            
           }
 
+          def dropMatchErrorCatchAll(cases: List[CaseDef]): List[CaseDef] =
+            if (!opt.virtPatmat) cases
+            else cases filter {
+                   case CaseDef(pat, EmptyTree, Throw(Apply(Select(New(exTpt), nme.CONSTRUCTOR), _))) if (treeInfo.isWildcardArg(pat) && (exTpt.tpe.typeSymbol eq MatchErrorClass)) => false
+                   case CaseDef(pat, guard, body) => true
+                 }
+
           DefDef(m, (fun.body: @unchecked) match {
             case Match(selector, cases) =>
-              dupMatch(selector, cases)
+              dupMatch(selector, dropMatchErrorCatchAll(cases))
             case Block((vd: ValDef) :: Nil, Match(selector, cases)) => // can't factor this out using an extractor due to bugs in the old pattern matcher
-              dupMatch(selector, cases, m => Block(List(vd), m))
+              dupMatch(selector, dropMatchErrorCatchAll(cases), m => Block(List(vd), m))
             // virtpatmat -- TODO: find a better way to keep this in synch with the code generated by patmatvirtualizer
             case Apply(Apply(TypeApply(Select(tgt, nme.runOrElse), targs), args_scrut), args_pm) if opt.virtPatmat =>
               object noOne extends Transformer {
diff --git a/test/files/run/virtpatmat_partial.check b/test/files/run/virtpatmat_partial.check
index 093020ce05..1555eca82b 100644
--- a/test/files/run/virtpatmat_partial.check
+++ b/test/files/run/virtpatmat_partial.check
@@ -1,2 +1,4 @@
 Map(a -> Some(1), b -> None)
-Map(a -> 1)
\ No newline at end of file
+79
+undefined
+Map(a -> 1)
diff --git a/test/files/run/virtpatmat_partial.scala b/test/files/run/virtpatmat_partial.scala
index c408b31983..6597f2f5ae 100644
--- a/test/files/run/virtpatmat_partial.scala
+++ b/test/files/run/virtpatmat_partial.scala
@@ -4,6 +4,29 @@ object Test extends App {
 
   val res = a collect {case (p, Some(a)) => (p, a)}
 
+  final val GT = 79
+  final val GTGT = 93
+  final val GTGTGT = 94
+  final val GTEQ = 81
+  final val GTGTEQ = 113
+  final val GTGTGTEQ = 114
+  final val ASSIGN = 75
+
+  def acceptClosingAngle(in: Int) {
+    val closers: PartialFunction[Int, Int] = {
+      case GTGTGTEQ => GTGTEQ
+      case GTGTGT   => GTGT
+      case GTGTEQ   => GTEQ
+      case GTGT     => GT
+      case GTEQ     => ASSIGN
+    }
+    if (closers isDefinedAt in) println(closers(in))
+    else println("undefined")
+  }
+
+  acceptClosingAngle(GTGT)
+  acceptClosingAngle(ASSIGN)
+
   // should uncurry to:
   // val res: Map[String,Int] = a.collect[(String, Int), Map[String,Int]](
   //   new PartialFunction[(String, Option[Int]),(String, Int)]  {