From 2ff4ba769e17e1eebd6419bfdbf9022129b5cd6a Mon Sep 17 00:00:00 2001
From: Szymon Rodziewicz <szymonrodant@gmail.com>
Date: Thu, 16 Nov 2023 19:09:49 +0100
Subject: [PATCH] Avoid too eager transform of outer for lhs & accessor rhs

---
 .../dotty/tools/dotc/transform/Constructors.scala  |  5 +++++
 tests/pos/i18927.scala                             | 14 ++++++++++++++
 2 files changed, 19 insertions(+)
 create mode 100644 tests/pos/i18927.scala

diff --git a/compiler/src/dotty/tools/dotc/transform/Constructors.scala b/compiler/src/dotty/tools/dotc/transform/Constructors.scala
index 9df98292fe84..e465e42fe8d8 100644
--- a/compiler/src/dotty/tools/dotc/transform/Constructors.scala
+++ b/compiler/src/dotty/tools/dotc/transform/Constructors.scala
@@ -15,6 +15,7 @@ import Symbols.*
 import Decorators.*
 import DenotTransformers.*
 import collection.mutable
+import Types.*
 
 object Constructors {
   val name: String = "constructors"
@@ -197,6 +198,10 @@ class Constructors extends MiniPhase with IdentityDenotTransformer { thisPhase =
              ) &&
              fn.symbol.info.resultType.classSymbol == outerParam.info.classSymbol =>
           ref(outerParam)
+        case Assign(lhs, rhs) if lhs.symbol.name == nme.OUTER => // not transform LHS of assignment to $outer field
+            cpy.Assign(tree)(lhs, super.transform(rhs))
+        case dd: DefDef if dd.name.endsWith(nme.OUTER.asSimpleName) => // not transform RHS of outer accessor
+          dd
         case tree: RefTree if tree.symbol.is(ParamAccessor) && tree.symbol.name == nme.OUTER =>
           ref(outerParam)
         case _ =>
diff --git a/tests/pos/i18927.scala b/tests/pos/i18927.scala
new file mode 100644
index 000000000000..1549335544c7
--- /dev/null
+++ b/tests/pos/i18927.scala
@@ -0,0 +1,14 @@
+class A
+
+class B {
+  val a = new A
+
+  class C(i: Int) {
+    def this() = {
+      this(1)
+      class Inner() {
+        println(a)
+      }
+    }
+  }
+}
\ No newline at end of file