Tweak: Print Ranges like regular types

Author: odersky

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

@@ -6045,14 +6045,10 @@ object Types {
   /** A range of possible types between lower bound `lo` and upper bound `hi`.
    *  Only used internally in `ApproximatingTypeMap`.
    */
-  case class Range(lo: Type, hi: Type) extends UncachedGroundType {
+  case class Range(lo: Type, hi: Type) extends UncachedGroundType:
     assert(!lo.isInstanceOf[Range])
     assert(!hi.isInstanceOf[Range])
 
-    override def toText(printer: Printer): Text =
-      lo.toText(printer) ~ ".." ~ hi.toText(printer)
-  }
-
   /** Approximate wildcards by their bounds */
   class AvoidWildcardsMap(using Context) extends ApproximatingTypeMap:
     protected def mapWild(t: WildcardType) =

compiler/src/dotty/tools/dotc/printing/PlainPrinter.scala

@@ -278,6 +278,8 @@ class PlainPrinter(_ctx: Context) extends Printer {
             case ex: Throwable => Str("...")
           }
         "LazyRef(" ~ refTxt ~ ")"
+      case Range(lo, hi) =>
+        toText(lo) ~ ".." ~ toText(hi)
       case _ =>
         tp.fallbackToText(this)
     }