Make the name uniqification more selective.

We need not, and should not, rename definitions
beyond the scope of the async transform, e.g.
in nested classes of function bodies.

2 files changed, 12 insertions, 12 deletions

diff --git a/src/main/scala/scala/async/AnfTransform.scala b/src/main/scala/scala/async/AnfTransform.scala
index d216e44..a2d21f6 100644
--- a/src/main/scala/scala/async/AnfTransform.scala
+++ b/src/main/scala/scala/async/AnfTransform.scala
@@ -31,20 +31,20 @@ private[async] final case class AnfTransform[C <: Context](c: C) {
     * This step is needed to allow us to safely merge blocks during the `inline` transform below.
     */
   private final class UniqueNames(tree: Tree) extends Transformer {
-    class DuplicateNameTraverser extends AsyncTraverser {
-      val result = collection.mutable.Buffer[Name]()
-
-      override def traverse(tree: Tree) {
-        tree match {
-          case dt: DefTree => result += dt.symbol.name
-          case _           => super.traverse(tree)
+    val repeatedNames: Set[Symbol] = {
+      class DuplicateNameTraverser extends AsyncTraverser {
+        val result = collection.mutable.Buffer[Symbol]()
+
+        override def traverse(tree: Tree) {
+          tree match {
+            case dt: DefTree => result += dt.symbol
+            case _           => super.traverse(tree)
+          }
         }
       }
-    }
-    val repeatedNames: Set[Name] = {
       val dupNameTraverser = new DuplicateNameTraverser
       dupNameTraverser.traverse(tree)
-      dupNameTraverser.result.groupBy(x => x).filter(_._2.size > 1).keySet
+      dupNameTraverser.result.groupBy(x => x.name).filter(_._2.size > 1).values.flatten.toSet[Symbol]
     }
 
     /** Stepping outside of the public Macro API to call [[scala.reflect.internal.Symbols.Symbol.name_=]] */
@@ -54,7 +54,7 @@ private[async] final case class AnfTransform[C <: Context](c: C) {
 
     override def transform(tree: Tree): Tree = {
       tree match {
-        case defTree: DefTree if repeatedNames(defTree.symbol.name) =>
+        case defTree: DefTree if repeatedNames(defTree.symbol) =>
           val trans = super.transform(defTree)
           val origName = defTree.symbol.name
           val sym = defTree.symbol.asInstanceOf[symtab.Symbol]
diff --git a/src/test/scala/scala/async/run/hygiene/Hygiene.scala b/src/test/scala/scala/async/run/hygiene/Hygiene.scala
index 5306ecc..9d1df21 100644
--- a/src/test/scala/scala/async/run/hygiene/Hygiene.scala
+++ b/src/test/scala/scala/async/run/hygiene/Hygiene.scala
@@ -76,7 +76,7 @@ class HygieneSpec {
       val f1 = async { state + 2 }
       val x  = await(f1)
       val y  = await(async { result })
-      val z  = await(async { resume() })
+      val z  = await(async(await(async { resume() })))
       (x, y, z)
     }
     res._1 mustBe (25)