More fixes

Author: odersky

compiler/src/dotty/tools/dotc/core/TypeOps.scala

@@ -71,11 +71,14 @@ trait TypeOps { this: Context => // TODO: Make standalone object.
               idx += 1
             }
             throw new AssertionError(ex"$pre contains no matching argument for ${tparam.showLocated} ")
-          case OrType(tp1, tp2) => argForParam(tp1, cls) | argForParam(tp2, cls)
-          case AndType(tp1, tp2) => argForParam(tp1, cls) & argForParam(tp2, cls)
-          case _ =>
+          case OrType(tp1, tp2) => argForParam(tp1, tparam) | argForParam(tp2, tparam)
+          case AndType(tp1, tp2) => argForParam(tp1, tparam) & argForParam(tp2, tparam)
+          case base =>
             if (pre.termSymbol is Package) argForParam(pre.select(nme.PACKAGE), tparam)
-            else throw new AssertionError(ex"$pre contains no matching argument for ${tparam.showLocated} ")
+            else {
+              // throw new AssertionError(ex"$pre contains no matching argument for ${tparam.showLocated}, base = $base") // DEBUG
+              tp
+            }
         }
       }
 

compiler/src/dotty/tools/dotc/core/Types.scala

@@ -2182,6 +2182,8 @@ object Types {
    */
   abstract case class SuperType(thistpe: Type, supertpe: Type) extends CachedProxyType with SingletonType {
     override def underlying(implicit ctx: Context) = supertpe
+    override def superType(implicit ctx: Context) =
+      thistpe.baseType(supertpe.typeSymbol)
     def derivedSuperType(thistpe: Type, supertpe: Type)(implicit ctx: Context) =
       if ((thistpe eq this.thistpe) && (supertpe eq this.supertpe)) this
       else SuperType(thistpe, supertpe)

compiler/src/dotty/tools/dotc/typer/RefChecks.scala

@@ -13,6 +13,7 @@ import scala.collection.{ mutable, immutable }
 import ast._
 import Trees._
 import TreeTransforms._
+import config.Printers.{checks, noPrinter}
 import util.DotClass
 import scala.util.{Try, Success, Failure}
 import config.{ScalaVersion, NoScalaVersion}
@@ -652,7 +653,13 @@ object RefChecks {
     // 4. Check that every defined member with an `override` modifier overrides some other member.
     for (member <- clazz.info.decls)
       if (member.isAnyOverride && !(clazz.thisType.baseClasses exists (hasMatchingSym(_, member)))) {
-        // for (bc <- clazz.info.baseClasses.tail) Console.println("" + bc + " has " + bc.info.decl(member.name) + ":" + bc.info.decl(member.name).tpe);//DEBUG
+        if (checks != noPrinter) {
+          for (bc <- clazz.info.baseClasses.tail) {
+            val sym = bc.info.decl(member.name).symbol
+            if (sym.exists)
+              checks.println(i"$bc has $sym: ${clazz.thisType.memberInfo(sym)}")
+          }
+        }
 
         val nonMatching = clazz.info.member(member.name).altsWith(alt => alt.owner != clazz)
         nonMatching match {

tests/pos/points.scala renamed to tests/neg/points.scala

@@ -3,6 +3,6 @@ class Point extends Comparable[Point] {
 }
 
 class ColoredPoint extends Point with Comparable[ColoredPoint] {
-  override def compareTo(other: ColoredPoint): Int = ???
+  override def compareTo(other: ColoredPoint): Int = ??? // error: overridden method has different signature
 }