Fixes to MacroTransform and TreeTransformer

1) Make local context go to module class if the tree symbol is a package val.
   Perviously, this gave the wrong context owner for package definitions.

2) Add a hook to define the phase in which a transform should be run.

2 files changed, 20 insertions, 4 deletions

diff --git a/src/dotty/tools/dotc/transform/MacroTransform.scala b/src/dotty/tools/dotc/transform/MacroTransform.scala
index 1ed9e68c2..0ee92bccd 100644
--- a/src/dotty/tools/dotc/transform/MacroTransform.scala
+++ b/src/dotty/tools/dotc/transform/MacroTransform.scala
@@ -7,6 +7,7 @@ import Phases._
 import ast.Trees._
 import Contexts._
 import Symbols._
+import Flags.PackageVal
 import Decorators._
 
 /** A base class for transforms.
@@ -18,15 +19,24 @@ abstract class MacroTransform extends Phase {
 
   override def run(implicit ctx: Context): Unit = {
     val unit = ctx.compilationUnit
-    unit.tpdTree = newTransformer.transform(unit.tpdTree)
+    unit.tpdTree = newTransformer.transform(unit.tpdTree)(ctx.withPhase(transformPhase))
   }
 
   protected def newTransformer(implicit ctx: Context): Transformer
 
+  /** The phase in which the transformation should be run.
+   *  By default this is the phase given by the this macro transformer,
+   *  but it could be overridden to be the phase following that one.
+   */
+  protected def transformPhase(implicit ctx: Context): Phase = this
+
   class Transformer extends TreeMap {
 
-    protected def localCtx(tree: Tree)(implicit ctx: Context) =
-      ctx.fresh.setTree(tree).setOwner(tree.symbol)
+    protected def localCtx(tree: Tree)(implicit ctx: Context) = {
+      val sym = tree.symbol
+      val owner = if (sym is PackageVal) sym.moduleClass else sym
+      ctx.fresh.setTree(tree).setOwner(owner)
+    }
 
     /** The current enclosing class
      *  @pre  We must be inside a class
diff --git a/src/dotty/tools/dotc/transform/TreeTransform.scala b/src/dotty/tools/dotc/transform/TreeTransform.scala
index 2bc733465..8e7c4f6d0 100644
--- a/src/dotty/tools/dotc/transform/TreeTransform.scala
+++ b/src/dotty/tools/dotc/transform/TreeTransform.scala
@@ -5,6 +5,7 @@ import dotty.tools.dotc.ast.tpd
 import dotty.tools.dotc.core.Contexts.Context
 import dotty.tools.dotc.core.Phases.Phase
 import dotty.tools.dotc.core.Symbols.Symbol
+import dotty.tools.dotc.core.Flags.PackageVal
 import dotty.tools.dotc.ast.Trees._
 import dotty.tools.dotc.core.Decorators._
 import scala.annotation.tailrec
@@ -883,7 +884,12 @@ object TreeTransforms {
         }
       } else tree
 
-    def localContext(owner: Symbol)(implicit ctx: Context) = ctx.fresh.setOwner(owner)
+    // TODO merge with localCtx in MacroTransform
+    // Generally: If we will keep MacroTransform, merge common behavior with TreeTransform
+    def localContext(sym: Symbol)(implicit ctx: Context) = {
+      val owner = if (sym is PackageVal) sym.moduleClass else sym
+      ctx.fresh.setOwner(owner)
+    }
 
     final private[TreeTransforms] def transformNamed(tree: NameTree, info: TransformerInfo, cur: Int)(implicit ctx: Context): Tree =
       tree match {