derivedNamedType -> derivedSelect

Performing refined/typeref reduction everywhere

3 files changed, 17 insertions, 12 deletions

diff --git a/src/dotty/tools/dotc/core/Substituters.scala b/src/dotty/tools/dotc/core/Substituters.scala
index 26095450e..27a2722f2 100644
--- a/src/dotty/tools/dotc/core/Substituters.scala
+++ b/src/dotty/tools/dotc/core/Substituters.scala
@@ -13,7 +13,7 @@ trait Substituters { this: Context =>
         if (tp.binder eq from) tp.copy(to.asInstanceOf[tp.BT]) else tp
       case tp: NamedType =>
         if (tp.symbol.isStatic) tp
-        else tp.derivedNamedType(subst(tp.prefix, from, to, map))
+        else tp.derivedSelect(subst(tp.prefix, from, to, map))
       case _: ThisType | NoPrefix =>
         tp
       case tp: RefinedType =>
@@ -29,7 +29,7 @@ trait Substituters { this: Context =>
         val sym = tp.symbol
         if (sym eq from) return to
         if (sym.isStatic && !from.isStatic) tp
-        else tp.derivedNamedType(subst1(tp.prefix, from, to, map))
+        else tp.derivedSelect(subst1(tp.prefix, from, to, map))
       case _: ThisType | _: BoundType | NoPrefix =>
         tp
       case tp: RefinedType =>
@@ -47,7 +47,7 @@ trait Substituters { this: Context =>
         if (sym eq from1) return to1
         if (sym eq from2) return to2
         if (sym.isStatic && !from1.isStatic && !from2.isStatic) tp
-        else tp.derivedNamedType(subst2(tp.prefix, from1, to1, from2, to2, map))
+        else tp.derivedSelect(subst2(tp.prefix, from1, to1, from2, to2, map))
       case _: ThisType | _: BoundType | NoPrefix =>
         tp
       case tp: RefinedType =>
@@ -70,7 +70,7 @@ trait Substituters { this: Context =>
           ts = ts.tail
         }
         if (sym.isStatic && !existsStatic(from)) tp
-        else tp.derivedNamedType(subst(tp.prefix, from, to, map))
+        else tp.derivedSelect(subst(tp.prefix, from, to, map))
       case _: ThisType | _: BoundType | NoPrefix =>
         tp
       case tp: RefinedType =>
@@ -93,7 +93,7 @@ trait Substituters { this: Context =>
           ts = ts.tail
         }
         if (sym.isStatic && !existsStatic(from)) tp
-        else tp.derivedNamedType(substSym(tp.prefix, from, to, map))
+        else tp.derivedSelect(substSym(tp.prefix, from, to, map))
       case _: ThisType | _: BoundType | NoPrefix =>
         tp
       case tp: RefinedType =>
@@ -109,7 +109,7 @@ trait Substituters { this: Context =>
         if (clazz eq from) to else tp
       case tp: NamedType =>
         if (tp.symbol.isStaticOwner) tp
-        else tp.derivedNamedType(substThis(tp.prefix, from, to, map))
+        else tp.derivedSelect(substThis(tp.prefix, from, to, map))
       case _: BoundType | NoPrefix =>
         tp
       case tp: RefinedType =>
@@ -125,7 +125,7 @@ trait Substituters { this: Context =>
         if (rt eq from) to else tp
       case tp: NamedType =>
         if (tp.symbol.isStatic) tp
-        else tp.derivedNamedType(substThis(tp.prefix, from, to, map))
+        else tp.derivedSelect(substThis(tp.prefix, from, to, map))
       case _: ThisType | _: BoundType | NoPrefix =>
         tp
       case tp: RefinedType =>
@@ -141,7 +141,7 @@ trait Substituters { this: Context =>
         if (tp == from) to else tp
       case tp: NamedType =>
         if (tp.symbol.isStatic) tp
-        else tp.derivedNamedType(substParam(tp.prefix, from, to, map))
+        else tp.derivedSelect(substParam(tp.prefix, from, to, map))
       case _: ThisType | NoPrefix =>
         tp
       case tp: RefinedType =>
@@ -157,7 +157,7 @@ trait Substituters { this: Context =>
         if (tp.binder == from) to(tp.paramNum) else tp
       case tp: NamedType =>
         if (tp.symbol.isStatic) tp
-        else tp.derivedNamedType(substParams(tp.prefix, from, to, map))
+        else tp.derivedSelect(substParams(tp.prefix, from, to, map))
       case _: ThisType | NoPrefix | _: RefinedThis =>
         tp
       case tp: RefinedType =>
diff --git a/src/dotty/tools/dotc/core/Types.scala b/src/dotty/tools/dotc/core/Types.scala
index 03b55736c..a230e9bbd 100644
--- a/src/dotty/tools/dotc/core/Types.scala
+++ b/src/dotty/tools/dotc/core/Types.scala
@@ -690,7 +690,7 @@ object Types {
       if (res.exists) res else NamedType.withSym(this, sym)
     }
 
-    private def lookupRefined(pre: Type, name: Name)(implicit ctx: Context): Type = pre.stripTypeVar match {
+    protected def lookupRefined(pre: Type, name: Name)(implicit ctx: Context): Type = pre.stripTypeVar match {
       case pre: RefinedType =>
         if (pre.refinedName ne name) lookupRefined(pre.parent, name)
         else pre.refinedInfo match {
@@ -1452,13 +1452,18 @@ object Types {
       ctx.underlyingRecursions -= 1
     }
 
+/* not needed
     def derivedNamedType(prefix: Type)(implicit ctx: Context): NamedType =
       if (prefix eq this.prefix) this
       else newLikeThis(prefix)
+*/
 
     def derivedSelect(prefix: Type)(implicit ctx: Context): Type =
       if (prefix eq this.prefix) this
-      else prefix select this.name
+      else {
+        val res = lookupRefined(this, name)
+        if (res.exists) res else newLikeThis(prefix)
+      }
 
     /** Create a NamedType of the same kind as this type, if possible,
      *  but with a new prefix. For HasFixedSym instances another such
diff --git a/src/dotty/tools/dotc/core/transform/Erasure.scala b/src/dotty/tools/dotc/core/transform/Erasure.scala
index 201dd107f..a0438fc4f 100644
--- a/src/dotty/tools/dotc/core/transform/Erasure.scala
+++ b/src/dotty/tools/dotc/core/transform/Erasure.scala
@@ -38,7 +38,7 @@ object Erasure {
       if (sym.isClass)
         /*if (sym.isDerivedValueClass) eraseDerivedValueClassRef(tref)
         else */if (sym.owner is Package) normalizeClass(sym.asClass).typeConstructor
-        else tp.derivedNamedType(erasure(tp.prefix))
+        else tp.derivedSelect(erasure(tp.prefix))
       else erasure(tp.info)
     case tp: RefinedType =>
       val parent = tp.parent