Merge pull request #4139 from dotty-staging/fix-asFunction-owner

Fix owners of AsFunction applied expressions

Author: nicolasstucki

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

@@ -1,7 +1,7 @@
 package dotty.tools.dotc.core.quoted
 
 import dotty.tools.dotc.ast.Trees._
-import dotty.tools.dotc.ast.tpd
+import dotty.tools.dotc.ast.{TreeTypeMap, tpd}
 import dotty.tools.dotc.config.Printers._
 import dotty.tools.dotc.core.Constants.Constant
 import dotty.tools.dotc.core.Contexts._
@@ -137,13 +137,12 @@ object PickledQuotes {
     def x1Ref() = ref(x1.symbol)
     def rec(f: Tree): Tree = f match {
       case closureDef(ddef) =>
-        new TreeMap() {
-          private val paramSym = ddef.vparamss.head.head.symbol
-          override def transform(tree: tpd.Tree)(implicit ctx: Context): tpd.Tree = tree match {
-            case tree: Ident if tree.symbol == paramSym => x1Ref().withPos(tree.pos)
-            case _ => super.transform(tree)
-          }
-        }.transform(ddef.rhs)
+        val paramSym = ddef.vparamss.head.head.symbol
+        new TreeTypeMap(
+          oldOwners = ddef.symbol :: Nil,
+          newOwners = ctx.owner :: Nil,
+          treeMap = tree => if (tree.symbol == paramSym) x1Ref().withPos(tree.pos) else tree
+        ).transform(ddef.rhs)
       case Block(stats, expr) =>
         val applied = rec(expr)
         if (stats.isEmpty) applied

tests/run-with-compiler/quote-ackermann-1.check

@@ -0,0 +1,4 @@
+13
+29
+61
+125

tests/run-with-compiler/quote-ackermann-1.scala

@@ -0,0 +1,25 @@
+import scala.quoted._
+
+import dotty.tools.dotc.quoted.Toolbox._
+
+object Test {
+
+  def main(args: Array[String]): Unit = {
+    val ack3 = ackermann(3).run
+    println(ack3(1))
+    println(ack3(2))
+    println(ack3(3))
+    println(ack3(4))
+  }
+
+  def ackermann(m: Int): Expr[Int => Int] = {
+    if (m == 0) '{ n => n + 1 }
+    else '{ n =>
+      def `ackermann(m-1)`(n: Int): Int = ~ackermann(m - 1)('(n)) // Expr[Int => Int] applied to Expr[Int]
+      def `ackermann(m)`(n: Int): Int =
+        if (n == 0) `ackermann(m-1)`(1) else `ackermann(m-1)`(`ackermann(m)`(n - 1))
+      `ackermann(m)`(n)
+    }
+  }
+
+}