Normalize parents to be class refs

Previously, alias type refs were also accepted. But this is the wrong assumption for computeMembersNames. So, e.g. instead of leaving an AnyRef we now expand to Object.

Also making ==, != take an Any instead of Object

4 files changed, 9 insertions, 8 deletions

diff --git a/src/dotty/tools/dotc/core/Definitions.scala b/src/dotty/tools/dotc/core/Definitions.scala
index 96e4f0138..a2527c9f2 100644
--- a/src/dotty/tools/dotc/core/Definitions.scala
+++ b/src/dotty/tools/dotc/core/Definitions.scala
@@ -45,7 +45,7 @@ class Definitions(implicit ctx: Context) {
           if (tpe.typeParams.nonEmpty) tpe.appliedTo(typeParam.typeRef)
           else tpe
         val parents = parentConstrs.toList map instantiate
-        val parentRefs: List[TypeRef] = ctx.normalizeToRefs(parents, cls, paramDecls)
+        val parentRefs: List[TypeRef] = ctx.normalizeToClassRefs(parents, cls, paramDecls)
         denot.info = ClassInfo(ScalaPackageClass.thisType, cls, parentRefs, paramDecls)
       }
     }
@@ -98,8 +98,8 @@ class Definitions(implicit ctx: Context) {
   lazy val AnyRefAlias: TypeSymbol = newAliasType(tpnme.AnyRef, ObjectType)
 
     lazy val Object_## = newMethod(ObjectClass, nme.HASHHASH, ExprType(IntType), Final)
-    lazy val Object_== = newMethod(ObjectClass, nme.EQ, methOfAnyRef(BooleanType), Final)
-    lazy val Object_!= = newMethod(ObjectClass, nme.NE, methOfAnyRef(BooleanType), Final)
+    lazy val Object_== = newMethod(ObjectClass, nme.EQ, methOfAny(BooleanType), Final)
+    lazy val Object_!= = newMethod(ObjectClass, nme.NE, methOfAny(BooleanType), Final)
     lazy val Object_eq = newMethod(ObjectClass, nme.eq, methOfAnyRef(BooleanType), Final)
     lazy val Object_ne = newMethod(ObjectClass, nme.ne, methOfAnyRef(BooleanType), Final)
     lazy val Object_isInstanceOf = newT1EmptyParamsMethod(ObjectClass, nme.isInstanceOf_Ob, _ => BooleanType, Final | Synthetic)
diff --git a/src/dotty/tools/dotc/core/TypeOps.scala b/src/dotty/tools/dotc/core/TypeOps.scala
index cce6cc350..c42f0bb36 100644
--- a/src/dotty/tools/dotc/core/TypeOps.scala
+++ b/src/dotty/tools/dotc/core/TypeOps.scala
@@ -86,10 +86,10 @@ trait TypeOps { this: Context =>
   }
 
   /** Normalize a list of parent types of class `cls` that may contain refinements
-   *  to a list of typerefs, by converting all refinements to member
+   *  to a list of typerefs referring to classes, by converting all refinements to member
    *  definitions in scope `decls`. Can add members to `decls` as a side-effect.
    */
-  def normalizeToRefs(parents: List[Type], cls: ClassSymbol, decls: Scope): List[TypeRef] = {
+  def normalizeToClassRefs(parents: List[Type], cls: ClassSymbol, decls: Scope): List[TypeRef] = {
 
     def enterArgBinding(formal: Symbol, info: Type) = {
       val typeArgFlag = if (formal is Local) TypeArgument else EmptyFlags
@@ -144,7 +144,8 @@ trait TypeOps { this: Context =>
         formals = formals.updated(name, tp1.typeParamNamed(name))
         normalizeToRef(tp1)
       case tp: TypeRef =>
-        tp
+        if (tp.symbol.isAliasType) normalizeToRef(tp.info.bounds.hi)
+        else tp
       case ErrorType =>
         defn.AnyClass.typeRef
       case _ =>
diff --git a/src/dotty/tools/dotc/core/pickling/UnPickler.scala b/src/dotty/tools/dotc/core/pickling/UnPickler.scala
index 177a8f21d..0351c948d 100644
--- a/src/dotty/tools/dotc/core/pickling/UnPickler.scala
+++ b/src/dotty/tools/dotc/core/pickling/UnPickler.scala
@@ -95,7 +95,7 @@ object UnPickler {
       case TempPolyType(tps, cinfo) => (tps, cinfo)
       case cinfo => (Nil, cinfo)
     }
-    val parentRefs = ctx.normalizeToRefs(parents, cls, decls)
+    val parentRefs = ctx.normalizeToClassRefs(parents, cls, decls)
     for (tparam <- tparams) {
       val tsym = decls.lookup(tparam.name)
       if (tsym.exists) tsym.setFlag(TypeParam)
diff --git a/src/dotty/tools/dotc/typer/Namer.scala b/src/dotty/tools/dotc/typer/Namer.scala
index 1908cbafd..56bd95257 100644
--- a/src/dotty/tools/dotc/typer/Namer.scala
+++ b/src/dotty/tools/dotc/typer/Namer.scala
@@ -365,7 +365,7 @@ class Namer { typer: Typer =>
         // pre-set info, so that parent types can refer to type params
         cls.info = adjustIfModule(ClassInfo(cls.owner.thisType, cls, Nil, decls, selfInfo))
         val parentTypes = parents map parentType
-        val parentRefs = ctx.normalizeToRefs(parentTypes, cls, decls)
+        val parentRefs = ctx.normalizeToClassRefs(parentTypes, cls, decls)
         val parentClsRefs =
           for ((parentRef, constr) <- parentRefs zip parents)
           yield checkClassTypeWithStablePrefix(parentRef, constr.pos)