Merge pull request #587 from retronym/ticket/5125

Fix @varargs forwarder generation in the presence of nested templates.

1 files changed, 18 insertions, 10 deletions

diff --git a/src/compiler/scala/tools/nsc/transform/UnCurry.scala b/src/compiler/scala/tools/nsc/transform/UnCurry.scala
index f01cbade18..8af12f3f10 100644
--- a/src/compiler/scala/tools/nsc/transform/UnCurry.scala
+++ b/src/compiler/scala/tools/nsc/transform/UnCurry.scala
@@ -77,9 +77,17 @@ abstract class UnCurry extends InfoTransform
     private var inConstructorFlag = 0L
     private val byNameArgs        = mutable.HashSet[Tree]()
     private val noApply           = mutable.HashSet[Tree]()
-    private val newMembers        = mutable.ArrayBuffer[Tree]()
+    private val newMembers        = mutable.Map[Symbol, mutable.Buffer[Tree]]()
     private val repeatedParams    = mutable.Map[Symbol, List[ValDef]]()
 
+    /** Add a new synthetic member for `currentOwner` */
+    private def addNewMember(t: Tree): Unit =
+      newMembers.getOrElseUpdate(currentOwner, mutable.Buffer()) += t
+
+    /** Process synthetic members for `owner`. They are removed form the `newMembers` as a side-effect. */
+    @inline private def useNewMembers[T](owner: Symbol)(f: List[Tree] => T): T =
+      f(newMembers.remove(owner).getOrElse(Nil).toList)
+
     @inline private def withInPattern[T](value: Boolean)(body: => T): T = {
       inPattern = value
       try body
@@ -573,7 +581,7 @@ abstract class UnCurry extends InfoTransform
             val vparamssNoRhs = dd.vparamss mapConserve (_ mapConserve {p =>
               treeCopy.ValDef(p, p.mods, p.name, p.tpt, EmptyTree)
             })
-            
+
             if (dd.symbol hasAnnotation VarargsClass) saveRepeatedParams(dd)
 
             withNeedLift(false) {
@@ -680,9 +688,8 @@ abstract class UnCurry extends InfoTransform
 
       tree match {
         /* Some uncurry post transformations add members to templates.
-         * When inside a template, the following sequence is available:
-         * - newMembers
-         * Any entry in this sequence will be added into the template
+         * 
+         * Members registered by `addMembers` for the current template are added
          * once the template transformation has finished.
          *
          * In particular, this case will add:
@@ -690,8 +697,10 @@ abstract class UnCurry extends InfoTransform
          */
         case Template(_, _, _) =>
           localTyper = typer.atOwner(tree, currentClass)
-          try deriveTemplate(tree)(transformTrees(newMembers.toList) ::: _)
-          finally newMembers.clear()
+          useNewMembers(currentClass) {
+            newMembers =>
+              deriveTemplate(tree)(transformTrees(newMembers) ::: _)
+          }
 
         case dd @ DefDef(_, _, _, vparamss0, _, rhs0) =>
           val flatdd = copyDefDef(dd)(
@@ -763,7 +772,7 @@ abstract class UnCurry extends InfoTransform
 
     /* Called during post transform, after the method argument lists have been flattened.
      * It looks for the method in the `repeatedParams` map, and generates a Java-style
-     * varargs forwarder. It then adds the forwarder to the `newMembers` sequence.
+     * varargs forwarder.
      */
     private def addJavaVarargsForwarders(dd: DefDef, flatdd: DefDef): DefDef = {
       if (!dd.symbol.hasAnnotation(VarargsClass) || !repeatedParams.contains(dd.symbol))
@@ -840,8 +849,7 @@ abstract class UnCurry extends InfoTransform
         case None =>
           // enter symbol into scope
           currentClass.info.decls enter forwsym
-          // add the method to `newMembers`
-          newMembers += forwtree
+          addNewMember(forwtree)
       }
 
       flatdd