Reord of superIds

1) We now keep an association between ClassSymbol and SuperId (instead of TypeRef and SuperId). That's better
   because superId's are deleted anyway after each run, so we gain nothing by keeping a stable ref.
2) hasChildren got dropped. It was too unreliable. The mere fact that someone take's the superId of a class
   does not means that that class has children.

1 files changed, 12 insertions, 11 deletions

diff --git a/src/dotty/tools/dotc/core/SymDenotations.scala b/src/dotty/tools/dotc/core/SymDenotations.scala
index 4ff6e629e..9ae5efb89 100644
--- a/src/dotty/tools/dotc/core/SymDenotations.scala
+++ b/src/dotty/tools/dotc/core/SymDenotations.scala
@@ -856,7 +856,7 @@ object SymDenotations {
       }
 
     private def computeBases(implicit ctx: Context): Unit = {
-      if (myBaseClasses == Nil) throw new CyclicReference(this)
+      if (myBaseClasses eq Nil) throw new CyclicReference(this)
       myBaseClasses = Nil
       val seen = new mutable.BitSet
       val locked = new mutable.BitSet
@@ -1012,24 +1012,25 @@ object SymDenotations {
     /** All non-private members of this class that have the given name.
      *  The elements of the returned pre-denotation all
      *  have existing symbols.
+     *  @param inherited  The method is called on a parent class from computeNPMembersNamed
      */
-    final def nonPrivateMembersNamed(name: Name)(implicit ctx: Context): PreDenotation = {
+    final def nonPrivateMembersNamed(name: Name, inherited: Boolean = false)(implicit ctx: Context): PreDenotation = {
       Stats.record("nonPrivateMembersNamed")
       if (Config.cacheMembersNamed) {
         var denots: PreDenotation = memberCache lookup name
         if (denots == null) {
-          denots = computeNPMembersNamed(name)
+          denots = computeNPMembersNamed(name, inherited)
           if (isFullyCompleted) memberCache.enter(name, denots)
         } else if (Config.checkCacheMembersNamed) {
-          val denots1 = computeNPMembersNamed(name)
+          val denots1 = computeNPMembersNamed(name, inherited)
           assert(denots.exists == denots1.exists, s"cache inconsistency: cached: $denots, computed $denots1, name = $name, owner = $this")
         }
         denots
-      } else computeNPMembersNamed(name)
+      } else computeNPMembersNamed(name, inherited)
     }
 
-    private[core] def computeNPMembersNamed(name: Name)(implicit ctx: Context): PreDenotation = /*>|>*/ Stats.track("computeNPMembersNamed") /*<|<*/ {
-      if (!classSymbol.hasChildren ||
+    private[core] def computeNPMembersNamed(name: Name, inherited: Boolean)(implicit ctx: Context): PreDenotation = /*>|>*/ Stats.track("computeNPMembersNamed") /*<|<*/ {
+      if (!inherited ||
           !Config.useFingerPrints ||
           (memberFingerPrint contains name)) {
         Stats.record("computeNPMembersNamed after fingerprint")
@@ -1043,7 +1044,7 @@ object SymDenotations {
             p.symbol.denot match {
               case parentd: ClassDenotation =>
                 denots1 union
-                  parentd.nonPrivateMembersNamed(name)
+                  parentd.nonPrivateMembersNamed(name, inherited = true)
                     .mapInherited(ownDenots, denots1, thisType)
               case _ =>
                 denots1
@@ -1197,11 +1198,11 @@ object SymDenotations {
     }
 
     /** Look first for members in package; if none are found look in package object */
-    override def computeNPMembersNamed(name: Name)(implicit ctx: Context): PreDenotation = {
-      val denots = super.computeNPMembersNamed(name)
+    override def computeNPMembersNamed(name: Name, inherited: Boolean)(implicit ctx: Context): PreDenotation = {
+      val denots = super.computeNPMembersNamed(name, inherited)
       if (denots.exists) denots
       else packageObj.moduleClass.denot match {
-        case pcls: ClassDenotation => pcls.computeNPMembersNamed(name)
+        case pcls: ClassDenotation => pcls.computeNPMembersNamed(name, inherited)
         case _ => denots
       }
     }