WIP move staging before pickling

Author: nicolasstucki

compiler/src/dotty/tools/dotc/Compiler.scala

@@ -45,8 +45,8 @@ class Compiler {
 
   /** Phases dealing with TASTY tree pickling and unpickling */
   protected def picklerPhases: List[List[Phase]] =
-    List(new Pickler) ::            // Generate TASTY info
     List(new Staging) ::            // Check quotation levels (while healing types) and expand macros
+    List(new Pickler) ::            // Generate TASTY info
     List(new ReifyQuotes) ::        // Turn quoted trees into explicit run-time data structures
     Nil
 

compiler/src/dotty/tools/dotc/transform/Staging.scala

@@ -83,7 +83,7 @@ class Staging extends MacroTransformWithImplicits {
       * These will be turned into splices using `addTags` and represent types spliced
       * explicitly.
       */
-    val explicitTags = new mutable.LinkedHashSet[TypeRef]()
+    val explicitTags = new mutable.LinkedHashSet[(TypeRef, Position)]()
 
     /** A stack of entered symbols, to be unwound after scope exit */
     var enteredSyms: List[Symbol] = Nil
@@ -111,7 +111,8 @@ class Staging extends MacroTransformWithImplicits {
           name = UniqueName.fresh("T".toTermName).toTypeName,
           flags = Synthetic,
           info = TypeAlias(tag.tpe.select(tpnme.UNARY_~)),
-          coord = typeRef.prefix.termSymbol.coord).asType
+          coord = alias.pos
+        ).asType
 
         ctx.typeAssigner.assignType(untpd.TypeDef(local.name, alias), local)
       }
@@ -126,11 +127,11 @@ class Staging extends MacroTransformWithImplicits {
         importedTags.clear()
 
         // The tree of the tag for each tag comes from a type ref e.g., ~t
-        val explicitTypeDefs = for (tref <- explicitTags) yield {
-          val tag = ref(tref.prefix.termSymbol)
+        val explicitTypeDefs = for ((tref, pos) <- explicitTags) yield {
+          val tag = ref(tref.prefix.termSymbol).withPos(pos)
           mkTagSymbolAndAssignType(tref, tag)
         }
-        val tagsExplicitTypeDefsPairs = explicitTags.zip(explicitTypeDefs)
+        val tagsExplicitTypeDefsPairs = explicitTags.map(_._1).zip(explicitTypeDefs)
         explicitTags.clear()
 
         // Maps type splices to type references of tags e.g., ~t -> some type T$1
@@ -243,7 +244,7 @@ class Staging extends MacroTransformWithImplicits {
         tp match {
           case tp: TypeRef if tp.symbol.isSplice =>
             if (inQuote) {
-              explicitTags += tp
+              explicitTags += Tuple2(tp, pos)
               outer.checkType(pos).foldOver(acc, tp)
             }
             else {
@@ -396,7 +397,8 @@ class Staging extends MacroTransformWithImplicits {
             tree.rhs match {
               case InlineSplice(_) =>
                 mapOverTree(enteredSyms) // Ignore output, only check PCP
-                cpy.DefDef(tree)(rhs = defaultValue(tree.rhs.tpe))
+//                cpy.DefDef(tree)(rhs = defaultValue(tree.rhs.tpe))
+                tree
               case _ =>
                 ctx.error(
                   """Malformed macro.