move test to simplify

Author: odersky

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

@@ -384,9 +384,7 @@ trait Inferencing { this: Typer =>
     // `qualifying`.
 
     val ownedVars = state.ownedVars
-    if ((ownedVars ne locked) && !ownedVars.isEmpty &&
-        !tree.isInstanceOf[Applications.IntegratedTypeArgs] // suppress interpolation in the middle of an extension method application
-        ) {
+    if ((ownedVars ne locked) && !ownedVars.isEmpty) {
       val qualifying = ownedVars -- locked
       if (!qualifying.isEmpty) {
         typr.println(i"interpolate $tree: ${tree.tpe.widen} in $state, owned vars = ${state.ownedVars.toList}%, %, previous = ${locked.toList}%, % / ${state.constraint}")

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

@@ -2206,7 +2206,11 @@ class Typer extends Namer
 
   /** Interpolate and simplify the type of the given tree. */
   protected def simplify(tree: Tree, pt: Type, locked: TypeVars)(implicit ctx: Context): tree.type = {
-    if (!tree.denot.isOverloaded) // for overloaded trees: resolve overloading before simplifying
+    if (!tree.denot.isOverloaded &&
+          // for overloaded trees: resolve overloading before simplifying
+        !tree.isInstanceOf[Applications.IntegratedTypeArgs]
+          // don't interpolatie in the middle of an extension method application
+       )
       if (!tree.tpe.widen.isInstanceOf[MethodOrPoly] // wait with simplifying until method is fully applied
           || tree.isDef)                             // ... unless tree is a definition
       {