Fix #3898: Do not interpret bindings for inlined parameters

Author: nicolasstucki

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

@@ -322,10 +322,19 @@ class ReifyQuotes extends MacroTransformWithImplicits {
             stats.foreach(markDef)
             mapOverTree(last)
           case Inlined(call, bindings, expansion @ Select(body, name)) if expansion.symbol.isSplice =>
-            // To maintain phase consistency, convert inlined expressions of the form
-            // `{ bindings; ~expansion }` to `~{ bindings; expansion }`
-            if (level == 0) transform(Splicer.splice(cpy.Inlined(tree)(call, bindings, body)))
-            else transform(cpy.Select(expansion)(cpy.Inlined(tree)(call, bindings, body), name))
+            if (level == 0) {
+              // To maintain phase consistency, we move the binding of the this parameter into the spliced code
+              val (thisBindings, otherBindings) = bindings.partition {
+                case vdef: ValDef => vdef.symbol.is(Synthetic) // Assume that only _this bindings are tagged with Synthetic
+                case _ => false
+              }
+              val splicedBody = Splicer.splice(seq(thisBindings, body))
+              transform(cpy.Inlined(tree)(call, otherBindings, splicedBody))
+            } else {
+              // To maintain phase consistency, convert inlined expressions of the form
+              // `{ bindings; ~expansion }` to `~{ bindings; expansion }`
+              transform(cpy.Select(expansion)(cpy.Inlined(tree)(call, bindings, body), name))
+            }
           case _: Import =>
             tree
           case tree: DefDef if tree.symbol.is(Macro) && level == 0 =>

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

@@ -19,6 +19,7 @@ object Splicer {
     case tree: RefTree => reflectiveSplice(tree)
     case tree: Apply => reflectiveSplice(tree)
     case tree: Inlined => reflectiveSplice(tree)
+    case tree: Block => reflectiveSplice(tree)
   }
 
   /** Splice the Tree for a Quoted expression which is constructed via a reflective call to the given method */

compiler/src/dotty/tools/dotc/typer/Inliner.scala

@@ -394,7 +394,7 @@ class Inliner(call: tpd.Tree, rhs: tpd.Tree)(implicit ctx: Context) {
     case tpe: ThisType if !canElideThis(tpe) && !thisProxy.contains(tpe.cls) =>
       val proxyName = s"${tpe.cls.name}_this".toTermName
       val proxyType = tpe.asSeenFrom(prefix.tpe, meth.owner)
-      thisProxy(tpe.cls) = newSym(proxyName, EmptyFlags, proxyType).termRef
+      thisProxy(tpe.cls) = newSym(proxyName, Synthetic, proxyType).termRef
       if (!tpe.cls.isStaticOwner)
         registerType(meth.owner.thisType) // make sure we have a base from which to outer-select
     case tpe: NamedType

tests/pos/i3898/quoted_1.scala

@@ -0,0 +1,5 @@
+import scala.quoted._
+object Macro {
+  inline def ff(args: Any*): String = ~impl('(args))
+  def impl(args: Expr[Seq[Any]]): Expr[String] = ""
+}

tests/pos/i3898/quoted_2.scala

@@ -0,0 +1,6 @@
+object Test {
+  def main(args: Array[String]): Unit = {
+    def x: Int = 5
+    Macro.ff(x)
+  }
+}

tests/pos/i3898b/quoted_1.scala

@@ -0,0 +1,5 @@
+import scala.quoted._
+object Macro {
+  inline def ff(x: Int, inline y: Int): String = ~impl('(x))
+  def impl(x: Expr[Int]): Expr[String] = ""
+}

tests/pos/i3898b/quoted_2.scala

@@ -0,0 +1,6 @@
+object Test {
+  def main(args: Array[String]): Unit = {
+    def z: Int = 5
+    Macro.ff(z, 5)
+  }
+}

tests/pos/quote-interpolator-core/quoted_1.scala

@@ -21,4 +21,7 @@ object FInterpolation {
     val args1: Expr[Seq[Any]] = liftSeq(args)
     '{  (~str).format(~args1: _*) }
   }
+
+  def hello = "hello"
+
 }

tests/pos/quote-interpolator-core/quoted_2.scala

@@ -5,4 +5,7 @@ object Test {
   println(ff"integer: ${5}%d")
   println(ff"string: ${"l"}%s")
   println(ff"${5}%s, ${6}%d, ${"hello"}%s")
+  val hello = "hello"
+  println(ff"${5}%s, ${6}%d, ${hello}%s")
+  println(ff"${5}%s, ${6}%d, ${FInterpolation.hello}%s")
 }