Encode quotes into List[String]

Author: nicolasstucki

compiler/src/dotty/tools/dotc/core/quoted/PickledQuotes.scala

@@ -16,13 +16,17 @@ import scala.runtime.quoted.Unpickler.Pickled
 object PickledQuotes {
   import tpd._
 
-  /** Pickle the quote into a TASTY string */
-  def pickleQuote(tree: Tree)(implicit ctx: Context): Pickled = {
-    if (ctx.reporter.hasErrors) List("<error>")
+  /** Pickle the quote into strings */
+  def pickleQuote(tree: Tree)(implicit ctx: Context): Tree = {
+    if (ctx.reporter.hasErrors) Literal(Constant("<error>"))
     else {
       val encapsulated = encapsulateQuote(tree)
       val pickled = pickle(encapsulated)
-      TastyString.pickle(pickled)
+      TastyString.pickle(pickled).foldRight[Tree](ref(defn.NilModule)) { (x, acc) =>
+        acc.select("::".toTermName)
+          .appliedToType(defn.StringType)
+          .appliedTo(Literal(Constant(x)))
+      }
     }
   }
 

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

@@ -266,11 +266,10 @@ class ReifyQuotes extends MacroTransform {
         makeHole(body1, splices, quote.tpe)
       else {
         val isType = quote.tpe.isRef(defn.QuotedTypeClass)
-        val strings = PickledQuotes.pickleQuote(body1).map(x => Literal(Constant(x)))
         ref(if (isType) defn.Unpickler_unpickleType else defn.Unpickler_unpickleExpr)
           .appliedToType(if (isType) body1.tpe else body1.tpe.widen)
           .appliedTo(
-            SeqLiteral(strings.toList, TypeTree(defn.StringType)),
+            PickledQuotes.pickleQuote(body1),
             SeqLiteral(splices, TypeTree(defn.AnyType)))
       }
     }.withPos(quote.pos)

library/src/scala/runtime/quoted/Unpickler.scala

@@ -5,10 +5,10 @@ import scala.quoted._
 /** Provides methods to unpickle `Expr` and `Type` trees. */
 object Unpickler {
 
-  /** Representation of pickled trees. For now it's String, but it
-   *  should be changed to some kind of TASTY bundle.
+  /** Representation of pickled trees. For now a List[String],
+   *  but it should be changed to some kind of TASTY bundle.
    */
-  type Pickled = Seq[String]
+  type Pickled = List[String]
 
   /** Unpickle `repr` which represents a pickled `Expr` tree,
    *  replacing splice nodes with `args`