Merge pull request #611 from dotty-staging/supercalls-traits-test

Add a test for supercalls in traits.

4 files changed, 14 insertions, 8 deletions

diff --git a/src/dotty/tools/dotc/core/TypeErasure.scala b/src/dotty/tools/dotc/core/TypeErasure.scala
index 65bc5e57f..fac795ef8 100644
--- a/src/dotty/tools/dotc/core/TypeErasure.scala
+++ b/src/dotty/tools/dotc/core/TypeErasure.scala
@@ -164,7 +164,7 @@ object TypeErasure {
     else if (sym.isConstructor) outer.addParam(sym.owner.asClass, erase(tp)(erasureCtx))
     else erase.eraseInfo(tp, sym)(erasureCtx) match {
       case einfo: MethodType if sym.isGetter && einfo.resultType.isRef(defn.UnitClass) =>
-        defn.BoxedUnitClass.typeRef
+        MethodType(Nil, Nil, defn.BoxedUnitClass.typeRef)
       case einfo =>
         einfo
     }
diff --git a/src/dotty/tools/dotc/transform/Memoize.scala b/src/dotty/tools/dotc/transform/Memoize.scala
index d96a52868..cbde1ef8a 100644
--- a/src/dotty/tools/dotc/transform/Memoize.scala
+++ b/src/dotty/tools/dotc/transform/Memoize.scala
@@ -50,15 +50,15 @@ import Decorators._
 
   override def transformDefDef(tree: DefDef)(implicit ctx: Context, info: TransformerInfo): Tree = {
     val sym = tree.symbol
-    
+
     def newField = ctx.newSymbol(
       owner = ctx.owner,
       name = sym.name.asTermName.fieldName,
       flags = Private | (if (sym is Stable) EmptyFlags else Mutable),
       info = sym.info.resultType,
       coord = tree.pos).enteredAfter(thisTransform)
-      
-    lazy val field = sym.field.orElse(newField).asTerm    
+
+    lazy val field = sym.field.orElse(newField).asTerm
     if (sym.is(Accessor, butNot = NoFieldNeeded))
       if (sym.isGetter) {
         tree.rhs.changeOwnerAfter(sym, field, thisTransform)
diff --git a/src/dotty/tools/dotc/transform/Mixin.scala b/src/dotty/tools/dotc/transform/Mixin.scala
index 8470be2ef..d2e7943f8 100644
--- a/src/dotty/tools/dotc/transform/Mixin.scala
+++ b/src/dotty/tools/dotc/transform/Mixin.scala
@@ -152,8 +152,14 @@ class Mixin extends MiniPhaseTransform with SymTransformer { thisTransform =>
     def traitInits(mixin: ClassSymbol): List[Tree] =
       for (getter <- mixin.info.decls.filter(getr => getr.isGetter && !wasDeferred(getr)).toList)
         yield {
-          // transformFollowing call is needed to make memoize & lazy vals run
-        transformFollowing(DefDef(implementation(getter.asTerm), superRef(initializer(getter)).appliedToNone))
+        // transformFollowing call is needed to make memoize & lazy vals run
+        val rhs = transformFollowing(superRef(initializer(getter)).appliedToNone)
+        // isCurrent: getter is a member of implementing class
+        val isCurrent = getter.is(ExpandedName) || ctx.atPhase(thisTransform) { implicit ctx =>
+          cls.info.member(getter.name).suchThat(_.isGetter).symbol == getter
+        }
+        if (isCurrent) transformFollowing(DefDef(implementation(getter.asTerm), rhs))
+        else rhs
       }
 
     def setters(mixin: ClassSymbol): List[Tree] =
diff --git a/src/dotty/tools/dotc/transform/ResolveSuper.scala b/src/dotty/tools/dotc/transform/ResolveSuper.scala
index 9c0e34256..0f1c448d9 100644
--- a/src/dotty/tools/dotc/transform/ResolveSuper.scala
+++ b/src/dotty/tools/dotc/transform/ResolveSuper.scala
@@ -83,7 +83,7 @@ class ResolveSuper extends MiniPhaseTransform with IdentityDenotTransformer { th
     def methodOverrides(mixin: ClassSymbol): List[Tree] = {
       def isOverridden(meth: Symbol) = meth.overridingSymbol(cls).is(Method, butNot = Deferred)
       def needsDisambiguation(meth: Symbol): Boolean =
-        meth.is(Method, butNot = PrivateOrDeferred) &&
+        meth.is(Method, butNot = PrivateOrAccessorOrDeferred) &&
           !isOverridden(meth) &&
           !meth.allOverriddenSymbols.forall(_ is Deferred)
       for (meth <- mixin.info.decls.toList if needsDisambiguation(meth))
@@ -107,5 +107,5 @@ class ResolveSuper extends MiniPhaseTransform with IdentityDenotTransformer { th
     else ddef
   }
 
-  private val PrivateOrDeferred = Private | Deferred
+  private val PrivateOrAccessorOrDeferred = Private | Accessor | Deferred
 }