Fix #4456: Pickle quote before compiling

Author: nicolasstucki

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

@@ -22,7 +22,13 @@ import scala.reflect.ClassTag
 object PickledQuotes {
   import tpd._
 
-  /** Pickle the quote into strings */
+  /** Pickle the tree of the a quoted.Expr */
+  def pickleExpr(tree: Tree)(implicit ctx: Context): scala.quoted.Expr[Any] = {
+    val pickled = pickleQuote(tree)
+    scala.runtime.quoted.Unpickler.unpickleExpr(pickled, Nil)
+  }
+
+  /** Pickle the tree of the quote into strings */
   def pickleQuote(tree: Tree)(implicit ctx: Context): scala.runtime.quoted.Unpickler.Pickled = {
     if (ctx.reporter.hasErrors) Nil
     else {

compiler/src/dotty/tools/dotc/core/tasty/TreeUnpickler.scala

@@ -19,7 +19,7 @@ import scala.collection.{ mutable, immutable }
 import config.Printers.pickling
 import typer.Checking
 import config.Config
-import dotty.tools.dotc.core.quoted.PickledQuotes
+import core.quoted.PickledQuotes
 import scala.quoted
 import scala.quoted.Types.TreeType
 import scala.quoted.Exprs.TreeExpr
@@ -1142,7 +1142,7 @@ class TreeUnpickler(reader: TastyReader,
       val idx = readNat()
       val args = until(end)(readTerm())
       val splice = splices(idx)
-      val reifiedArgs = args.map(arg => if (arg.isTerm) new TreeExpr(arg) else new TreeType(arg))
+      val reifiedArgs = args.map(arg => if (arg.isTerm) new TreeExpr(arg, PickledQuotes.pickleExpr(arg)) else new TreeType(arg))
       if (isType) {
         val quotedType = splice.asInstanceOf[Seq[Any] => quoted.Type[_]](reifiedArgs)
         PickledQuotes.quotedTypeToTree(quotedType)

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

@@ -3,11 +3,13 @@ package dotty.tools.dotc.quoted
 import dotty.tools.dotc.ast.Trees._
 import dotty.tools.dotc.ast.tpd
 import dotty.tools.dotc.core.Constants._
+import dotty.tools.dotc.core.Contexts.Context
+import dotty.tools.dotc.core.quoted.PickledQuotes
 import dotty.tools.dotc.printing.RefinedPrinter
 
 import scala.quoted.Expr
 import scala.runtime.BoxedUnit
-import scala.quoted.Exprs.LiftedExpr
+import scala.quoted.Exprs.{LiftedExpr, TreeExpr}
 import scala.runtime.quoted._
 
 /** Default runners for quoted expressions */
@@ -23,8 +25,12 @@ object Toolbox {
     ): Toolbox[T] = new Toolbox[T] {
 
     def run(expr: Expr[T]): T = expr match {
-      case expr: LiftedExpr[T] => expr.value
-      case _ => new QuoteDriver().run(expr, runSettings)
+      case expr: LiftedExpr[T] =>
+        expr.value
+      case expr: TreeExpr[Tree] @unchecked =>
+        new QuoteDriver().run(expr.pickled, runSettings)
+      case _ =>
+        new QuoteDriver().run(expr, runSettings)
     }
 
     def show(expr: Expr[T]): String = expr match {

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

@@ -60,7 +60,8 @@ object Splicer {
           case (arg, tp) =>
             assert(!tp.hasAnnotation(defn.InlineParamAnnot))
             // Replace argument by its binding
-            new scala.quoted.Exprs.TreeExpr(bindMap.getOrElse(arg, arg))
+            val arg1 = bindMap.getOrElse(arg, arg)
+            new scala.quoted.Exprs.TreeExpr(arg1, PickledQuotes.pickleExpr(arg1))
         }
         args1 ::: liftArgs(tp.resType, args.tail)
       case tp: PolyType =>

library/src/scala/quoted/Expr.scala

@@ -37,7 +37,8 @@ object Exprs {
   }
 
   /** An Expr backed by a tree. Only the current compiler trees are allowed. */
-  final class TreeExpr[Tree](val tree: Tree) extends quoted.Expr[Any] {
+  final class TreeExpr[Tree](val tree: Tree, pickle: => Expr[_]) extends quoted.Expr[Any] {
+    def pickled[T]: Expr[T] = pickle.asInstanceOf[Expr[T]]
     override def toString: String = s"Expr(<raw>)"
   }
 

tests/run/quote-run-in-macro-1.check

@@ -0,0 +1,2 @@
+1
+4

tests/run/quote-run-in-macro-1/quoted_1.scala

@@ -0,0 +1,10 @@
+import scala.quoted._
+
+import dotty.tools.dotc.quoted.Toolbox._
+
+object Macros {
+  inline def foo(i: Int): Int = ~{
+    val y: Int = ('(i)).run
+    y.toExpr
+  }
+}

tests/run/quote-run-in-macro-1/quoted_2.scala

@@ -0,0 +1,7 @@
+import Macros._
+object Test {
+  def main(args: Array[String]): Unit = {
+    println(foo(1))
+    println(foo(1  + 3))
+  }
+}