Add types to unpickle methods

Author: nicolasstucki

compiler/src/dotty/tools/dotc/quoted/QuoteContextImpl.scala

@@ -2628,13 +2628,13 @@ class QuoteContextImpl private (ctx: Context) extends QuoteContext, scala.intern
 
   end reflect
 
-  def unpickleExpr(pickledQuote: PickledQuote): scala.quoted.Expr[Any] =
+  def unpickleExpr[T](pickledQuote: PickledQuote): scala.quoted.Expr[T] =
     val tree = PickledQuotes.unpickleTerm(pickledQuote)(using reflect.rootContext)
-    new scala.internal.quoted.Expr(tree, hash)
+    new scala.internal.quoted.Expr(tree, hash).asInstanceOf[scala.quoted.Expr[T]]
 
-  def unpickleType(pickledQuote: PickledQuote): scala.quoted.Type[?] =
+  def unpickleType[T <: AnyKind](pickledQuote: PickledQuote): scala.quoted.Type[T] =
     val tree = PickledQuotes.unpickleTypeTree(pickledQuote)(using reflect.rootContext)
-    new scala.internal.quoted.Type(tree, hash)
+    new scala.internal.quoted.Type(tree, hash).asInstanceOf[scala.quoted.Type[T]]
 
   def exprMatch(scrutinee: scala.quoted.Expr[Any], pattern: scala.quoted.Expr[Any]): Option[Tuple] =
     treeMatch(scrutinee.unseal(using this), pattern.unseal(using this))

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

@@ -194,9 +194,9 @@ class ReifyQuotes extends MacroTransform {
        *
        *  Generate the code
        *  ```scala
-       *    qctx => qctx.asInstanceOf[QuoteContextInternal].<unpickleExpr|unpickleType>(
+       *    qctx => qctx.asInstanceOf[QuoteContextInternal].<unpickleExpr|unpickleType>[<type>](
        *      <pickledQuote>
-       *    ).asInstanceOf[scala.quoted.<Expr|Type>[<type>]]
+       *    )
        *  ```
        *  this closure is always applied directly to the actual context and the BetaReduce phase removes it.
        */
@@ -211,7 +211,7 @@ class ReifyQuotes extends MacroTransform {
         def callUnpickle(ts: List[Tree]) = {
           val qctx = ts.head.asInstance(defn.QuoteContextInternalClass.typeRef)
           val unpickleMethName = if isType then "unpickleType" else "unpickleExpr"
-          qctx.select(unpickleMethName.toTermName).appliedTo(pickledQuote).asInstance(quotedType)
+          qctx.select(unpickleMethName.toTermName).appliedToType(originalTp).appliedTo(pickledQuote)
         }
         Lambda(lambdaTpe, callUnpickle).withSpan(body.span)
       }

library/src/scala/internal/quoted/QuoteContextInternal.scala

@@ -10,12 +10,12 @@ trait QuoteContextInternal { self: scala.quoted.QuoteContext =>
   /** Unpickle `repr` which represents a pickled `Expr` tree,
    *  replacing splice nodes with `holes`
    */
-  def unpickleExpr(pickledQuote: PickledQuote): scala.quoted.Expr[Any]
+  def unpickleExpr[T](pickledQuote: PickledQuote): scala.quoted.Expr[T]
 
   /** Unpickle `repr` which represents a pickled `Type` tree,
    *  replacing splice nodes with `holes`
    */
-  def unpickleType(pickledQuote: PickledQuote): scala.quoted.Type[?]
+  def unpickleType[T <: AnyKind](pickledQuote: PickledQuote): scala.quoted.Type[T]
 
   /** Pattern matches the scrutinee against the pattern and returns a tuple
    *  with the matched holes if successful.