1 files changed, 41 insertions, 4 deletions
diff --git a/src/dotty/tools/dotc/transform/ElimRepeated.scala b/src/dotty/tools/dotc/transform/ElimRepeated.scala
index a362aee07..c78c012c3 100644
--- a/src/dotty/tools/dotc/transform/ElimRepeated.scala
+++ b/src/dotty/tools/dotc/transform/ElimRepeated.scala
@@ -32,10 +32,8 @@ class ElimRepeated extends TreeTransform with InfoTransformer { thisTransformer
     case tp @ MethodType(paramNames, paramTypes) =>
       val resultType1 = elimRepeated(tp.resultType)
       val paramTypes1 =
-        if (paramTypes.nonEmpty && paramTypes.last.isRepeatedParam) {
-          paramTypes.init :+
-            paramTypes.last.translateParameterized(defn.RepeatedParamClass, defn.SeqClass)
-        }
+        if (paramTypes.nonEmpty && paramTypes.last.isRepeatedParam)
+          paramTypes.init :+ paramTypes.last.underlyingIfRepeated(tp.isJava)
         else paramTypes
       tp.derivedMethodType(paramNames, paramTypes1, resultType1)
     case tp: PolyType =>
@@ -58,4 +56,43 @@ class ElimRepeated extends TreeTransform with InfoTransformer { thisTransformer
 
   override def transformTypeApply(tree: TypeApply)(implicit ctx: Context, info: TransformerInfo): Tree =
     transformTypeOfTree(tree)
+
+  override def transformDefDef(tree: DefDef)(implicit ctx: Context, info: TransformerInfo): Tree = {
+    assert(ctx.phase == thisTransformer)
+    def overridesJava = {
+      val overridden = tree.symbol.allOverriddenSymbols
+      overridden.hasNext && overridden.forall(_ is JavaDefined)
+    }
+    if (tree.symbol.info.isVarArgsMethod && overridesJava)
+      addVarArgsBridge(tree)(ctx.withPhase(thisTransformer.next))
+    else
+      tree
+  }
+
+  /** add varargs bridge method
+   */
+  private def addVarArgsBridge(ddef: DefDef)(implicit ctx: Context): Tree = {
+    val original = ddef.symbol.asTerm
+    val bridge = original.copy(
+      flags = ddef.symbol.flags &~ Private | Artifact,
+      info = toJavaVarArgs(ddef.symbol.info)).enteredAfter(thisTransformer).asTerm
+    val bridgeDef = polyDefDef(bridge, trefs => vrefss => {
+      val (vrefs :+ varArgRef) :: vrefss1 = vrefss
+      val elemtp = varArgRef.tpe.widen.argTypes.head
+      ref(original.termRef)
+        .appliedToTypes(trefs)
+        .appliedToArgs(vrefs :+ TreeGen.wrapArray(varArgRef, elemtp))
+        .appliedToArgss(vrefss1)
+    })
+    Thicket(ddef, bridgeDef)
+  }
+
+  private def toJavaVarArgs(tp: Type)(implicit ctx: Context): Type = tp match {
+    case tp: PolyType =>
+      tp.derivedPolyType(tp.paramNames, tp.paramBounds, toJavaVarArgs(tp.resultType))
+    case tp: MethodType =>
+      val inits :+ last = tp.paramTypes
+      val last1 = last.underlyingIfRepeated(isJava = true)
+      tp.derivedMethodType(tp.paramNames, inits :+ last1, tp.resultType)
+  }
 }