Fix #4456: Pickle quote before compiling

Author: nicolasstucki

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

@@ -41,7 +41,7 @@ object PickledQuotes {
         case value: Class[_] => ref(defn.Predef_classOf).appliedToType(classToType(value))
         case value=> Literal(Constant(value))
       }
-    case expr: TreeExpr[Tree] @unchecked => expr.tree
+    case expr: TreeExpr[Tree, Context] @unchecked => expr.tree
     case expr: FunctionAppliedTo[_, _] =>
       functionAppliedTo(quotedExprToTree(expr.f), quotedExprToTree(expr.x))
   }

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, ctx) 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 */
@@ -24,6 +26,10 @@ object Toolbox {
 
     def run(expr: Expr[T]): T = expr match {
       case expr: LiftedExpr[T] => expr.value
+      case expr: TreeExpr[Tree, Context] @unchecked =>
+        val pickled = PickledQuotes.pickleQuote(expr.tree)(expr.ctx)
+        val pickledQuote = scala.runtime.quoted.Unpickler.unpickleExpr(pickled, Nil)
+        new QuoteDriver().run(pickledQuote, runSettings)
       case _ => new QuoteDriver().run(expr, runSettings)
     }
 

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

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

library/src/scala/quoted/Expr.scala

@@ -37,7 +37,7 @@ 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, Ctx](val tree: Tree, val ctx: Ctx) extends quoted.Expr[Any] {
     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))
+  }
+}