From bf28a48e3ed856537ed8ed7586e0eeeba2437642 Mon Sep 17 00:00:00 2001
From: Martin Odersky <odersky@gmail.com>
Date: Sun, 5 May 2019 23:14:29 +0200
Subject: [PATCH] Fix #6395: Drop expected type in inlineCall

The Inliner ReTyper got confused if the expected type was an
extension method. We can fix this by simply not propafating the
expected type into the inline expansion.
---
 .../src/dotty/tools/dotc/core/SymDenotations.scala     |  2 +-
 compiler/src/dotty/tools/dotc/typer/Inliner.scala      | 10 +++++-----
 compiler/src/dotty/tools/dotc/typer/Typer.scala        |  4 ++--
 tests/pos/i6395.scala                                  |  5 +++++
 4 files changed, 13 insertions(+), 8 deletions(-)
 create mode 100644 tests/pos/i6395.scala

diff --git a/compiler/src/dotty/tools/dotc/core/SymDenotations.scala b/compiler/src/dotty/tools/dotc/core/SymDenotations.scala
index 71907eb83a18..8608a9ac4095 100644
--- a/compiler/src/dotty/tools/dotc/core/SymDenotations.scala
+++ b/compiler/src/dotty/tools/dotc/core/SymDenotations.scala
@@ -396,7 +396,7 @@ object SymDenotations {
         // need to use initial owner to disambiguate, as multiple private symbols with the same name
         // might have been moved from different origins into the same class
 
-    /** The name with which the denoting symbol was created */
+    /** The effective name with which the denoting symbol was created */
     final def originalName(implicit ctx: Context): Name = initial.effectiveName
 
     /** The owner with which the denoting symbol was created. */
diff --git a/compiler/src/dotty/tools/dotc/typer/Inliner.scala b/compiler/src/dotty/tools/dotc/typer/Inliner.scala
index 193a92f0000a..8ea445e82df8 100644
--- a/compiler/src/dotty/tools/dotc/typer/Inliner.scala
+++ b/compiler/src/dotty/tools/dotc/typer/Inliner.scala
@@ -61,7 +61,7 @@ object Inliner {
    *  @return   An `Inlined` node that refers to the original call and the inlined bindings
    *            and body that replace it.
    */
-  def inlineCall(tree: Tree, pt: Type)(implicit ctx: Context): Tree = {
+  def inlineCall(tree: Tree)(implicit ctx: Context): Tree = {
 
    /** Set the position of all trees logically contained in the expansion of
     *  inlined call `call` to the position of `call`. This transform is necessary
@@ -102,11 +102,11 @@ object Inliner {
 
     val tree1 = liftBindings(tree, identity)
     if (bindings.nonEmpty)
-      cpy.Block(tree)(bindings.toList, inlineCall(tree1, pt))
+      cpy.Block(tree)(bindings.toList, inlineCall(tree1))
     else if (enclosingInlineds.length < ctx.settings.XmaxInlines.value) {
       val body = bodyToInline(tree.symbol) // can typecheck the tree and thereby produce errors
       if (ctx.reporter.hasErrors) tree
-      else new Inliner(tree, body).inlined(pt, tree.sourcePos)
+      else new Inliner(tree, body).inlined(tree.sourcePos)
     }
     else
       errorTree(
@@ -384,7 +384,7 @@ class Inliner(call: tpd.Tree, rhsToInline: tpd.Tree)(implicit ctx: Context) {
     }
 
   /** The Inlined node representing the inlined call */
-  def inlined(pt: Type, sourcePos: SourcePosition): Tree = {
+  def inlined(sourcePos: SourcePosition): Tree = {
 
     if (callTypeArgs.length == 1)
       if (inlinedMethod == defn.Compiletime_constValue) {
@@ -509,7 +509,7 @@ class Inliner(call: tpd.Tree, rhsToInline: tpd.Tree)(implicit ctx: Context) {
       }
 
       // Run a typing pass over the inlined tree. See InlineTyper for details.
-      val expansion1 = inlineTyper.typed(expansion, pt)(inlineCtx)
+      val expansion1 = inlineTyper.typed(expansion)(inlineCtx)
 
       if (ctx.settings.verbose.value) {
         inlining.println(i"to inline = $rhsToInline")
diff --git a/compiler/src/dotty/tools/dotc/typer/Typer.scala b/compiler/src/dotty/tools/dotc/typer/Typer.scala
index f07563ec49f3..ce6a634d1601 100644
--- a/compiler/src/dotty/tools/dotc/typer/Typer.scala
+++ b/compiler/src/dotty/tools/dotc/typer/Typer.scala
@@ -2772,7 +2772,7 @@ class Typer extends Namer
                !ctx.isAfterTyper &&
                !ctx.reporter.hasErrors) {
         tree.tpe <:< wildApprox(pt)
-        readaptSimplified(Inliner.inlineCall(tree, pt))
+        readaptSimplified(Inliner.inlineCall(tree))
       }
       else if (tree.symbol.isScala2Macro) {
         if (ctx.settings.XignoreScala2Macros.value) {
@@ -2786,7 +2786,7 @@ class Typer extends Namer
           // As the macro is implemented in the bootstrapped library, it can only be used from the bootstrapped compiler.
           val Apply(TypeApply(Select(sc, _), _), args) = tree
           val newCall = ref(defn.InternalStringContextModule_f).appliedTo(sc).appliedToArgs(args)
-          Inliner.inlineCall(newCall, pt)
+          readaptSimplified(Inliner.inlineCall(newCall))
         } else {
           ctx.error("Scala 2 macro cannot be used in Dotty. See http://dotty.epfl.ch/docs/reference/dropped-features/macros.html", tree.sourcePos)
           tree
diff --git a/tests/pos/i6395.scala b/tests/pos/i6395.scala
new file mode 100644
index 000000000000..26faf3f52109
--- /dev/null
+++ b/tests/pos/i6395.scala
@@ -0,0 +1,5 @@
+object Foo {
+  inline def (self: Int) foo (that: Int): Int = 5
+  def (self: Int) bar: Int = self
+  1.foo(2).bar
+}
\ No newline at end of file