Address reviewers comments

Author: odersky

compiler/src/dotty/tools/dotc/transform/ByNameClosures.scala

@@ -29,7 +29,7 @@ class ByNameClosures extends TransformByNameApply with IdentityDenotTransformer
 
   override def phaseName: String = "byNameClosures"
 
-  override def mkClosure(arg: Tree, argType: Type)(implicit ctx: Context): Tree = {
+  override def mkByNameClosure(arg: Tree, argType: Type)(implicit ctx: Context): Tree = {
     val meth = ctx.newSymbol(
       ctx.owner, nme.ANON_FUN, Synthetic | Method, MethodType(Nil, Nil, argType))
     Closure(meth, _ => arg.changeOwnerAfter(ctx.owner, meth, thisTransformer))

compiler/src/dotty/tools/dotc/transform/HoistSuperArgs.scala

@@ -123,11 +123,12 @@ class HoistSuperArgs extends MiniPhaseTransform with IdentityDenotTransformer {
             val paramSyms = trefs.map(_.typeSymbol) ::: vrefss.flatten.map(_.symbol)
             val tmap = new TreeTypeMap(
               typeMap = new TypeMap {
+                lazy val origToParam = origParams.zip(paramSyms).toMap
                 def apply(tp: Type) = tp match {
                   case tp: NamedType
                   if (tp.symbol.owner == cls || tp.symbol.owner == constr) &&
                      tp.symbol.is(ParamOrAccessor) =>
-                    val mappedSym = origParams.zip(paramSyms).toMap.apply(tp.symbol)
+                    val mappedSym = origToParam(tp.symbol)
                     if (tp.symbol.isType) mappedSym.typeRef else mappedSym.termRef
                   case _ =>
                     mapOver(tp)

compiler/src/dotty/tools/dotc/transform/TransformByNameApply.scala

@@ -19,7 +19,7 @@ import ast.Trees._
 abstract class TransformByNameApply extends MiniPhaseTransform { thisTransformer: DenotTransformer =>
   import ast.tpd._
 
-  /** The info of the tree's symbol at phase Nullarify (i.e. before transformation) */
+  /** The info of the tree's symbol before it is potentially transformed in this phase */
   private def originalDenotation(tree: Tree)(implicit ctx: Context) =
     tree.symbol.denot(ctx.withPhase(thisTransformer))
 
@@ -32,7 +32,7 @@ abstract class TransformByNameApply extends MiniPhaseTransform { thisTransformer
     origDenot.info.isInstanceOf[ExprType] && exprBecomesFunction(origDenot)
   }
 
-  def mkClosure(arg: Tree, argType: Type)(implicit ctx: Context): Tree = unsupported(i"mkClosure($arg)")
+  def mkByNameClosure(arg: Tree, argType: Type)(implicit ctx: Context): Tree = unsupported(i"mkClosure($arg)")
 
   override def transformApply(tree: Apply)(implicit ctx: Context, info: TransformerInfo): Tree =
     ctx.traceIndented(s"transforming ${tree.show} at phase ${ctx.phase}", show = true) {
@@ -48,7 +48,7 @@ abstract class TransformByNameApply extends MiniPhaseTransform { thisTransformer
             wrap(qual)
           case _ =>
             if (isByNameRef(arg) || arg.symbol == defn.cbnArg) arg
-            else wrap(mkClosure(arg, argType))
+            else wrap(mkByNameClosure(arg, argType))
         }
       case _ =>
         arg