Set case on quote pattern type variables while desugaring

Author: nicolasstucki

compiler/src/dotty/tools/dotc/ast/Desugar.scala

@@ -384,8 +384,11 @@ object desugar {
           case tdef @ untpd.TypeDef(name, _) => !tdef.isBackquoted && name.isVarPattern
           case _ => false
         }
+        val untpdCaseTypeVariables = untpdTypeVariables.asInstanceOf[List[untpd.TypeDef]].map {
+          tdef => tdef.withMods(tdef.mods | Case)
+        }
         val pattern = if otherStats.isEmpty then expr else untpd.cpy.Block(tree)(otherStats, expr)
-        (untpdTypeVariables.asInstanceOf[List[untpd.TypeDef]], pattern)
+        (untpdCaseTypeVariables, pattern)
       case _ =>
         (Nil, tree)
 

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

@@ -242,7 +242,6 @@ trait QuotesAndSplices {
     val allTypeBindings = List.newBuilder[Bind]
     for tpVar <- typeTypeVariables do
       val sym = tpVar.symbol
-      sym.setFlag(Case)
       allTypeBindings += Bind(sym, untpd.Ident(nme.WILDCARD).withType(sym.info)).withSpan(tpVar.span)
 
     val body1 = inContext(patternCtx) {