Use desugarIdent

Author: nicolasstucki

compiler/src/dotty/tools/dotc/tastyreflect/ReflectionCompilerInterface.scala

@@ -309,6 +309,9 @@ class ReflectionCompilerInterface(val rootContext: core.Contexts.Context) extend
   def Ref_term(tp: TermRef)(using ctx: Context): Ref =
     withDefaultPos(tpd.ref(tp).asInstanceOf[tpd.RefTree])
 
+  def Ref_desugarIdent(tree: Ident)(using ctx: Context): Ref =
+    tpd.desugarIdent(tree).asInstanceOf[tpd.RefTree]
+
   def Ref_apply(sym: Symbol)(using ctx: Context): Ref = {
     assert(sym.isTerm)
     withDefaultPos(tpd.ref(sym).asInstanceOf[tpd.RefTree])

library/src/scala/internal/quoted/Matcher.scala

@@ -272,13 +272,12 @@ private[quoted] object Matcher {
             scrutinee =?= expr2
 
           /* Match selection */
-          case (ref: Ref, Select(qual2, _)) if scrutinee.symbol == pattern.symbol =>
-            ref match
-              case ref: Select => ref.qualifier =?= qual2
-              case _ =>
-                ref.tpe match
-                  case TermRef(qual: TermRef, _) => Ref.term(qual) =?= qual2
-                  case _ => matched
+          case (Select(qual1, _), Select(qual2, _)) if scrutinee.symbol == pattern.symbol =>
+            qual1 =?= qual2
+          case (ref: Ident, Select(qual2, _)) if scrutinee.symbol == pattern.symbol =>
+            Ref.desugarIdent(ref) match
+              case Select(qual1, _) => qual1 =?= qual2
+              case _ => matched
 
           /* Match reference */
           case (_: Ref, _: Ident) if scrutinee.symbol == pattern.symbol || summon[Env].get(scrutinee.symbol).contains(pattern.symbol) =>

library/src/scala/tasty/Reflection.scala

@@ -677,6 +677,10 @@ class Reflection(private[scala] val internal: CompilerInterface) { self =>
     def term(tp: TermRef)(using ctx: Context): Ref =
       internal.Ref_term(tp)
 
+    /** Desugar identifier into a select node. Return the tree itself if not possible */
+    def desugarIdent(tree: Ident)(using ctx: Context): Ref =
+      internal.Ref_desugarIdent(tree)
+
     /** Create a reference tree from a symbol
      *
      *  If `sym` refers to a class member `foo` in class `C`,

library/src/scala/tasty/reflect/CompilerInterface.scala

@@ -322,6 +322,9 @@ trait CompilerInterface {
   /** A tree representing the same reference as the given type */
   def Ref_term(tp: TermRef)(using ctx: Context): Ref
 
+  /** Desugar identifier into a select node. Return the tree itself if not possible */
+  def Ref_desugarIdent(tree: Ident)(using ctx: Context): Ref
+
   def Ref_apply(sym: Symbol)(using ctx: Context): Ref
 
   /** Tree representing a reference to definition with a given name */