From 2df52b954143e74f382276d9f9cca3102b4ceb29 Mon Sep 17 00:00:00 2001
From: odersky <odersky@gmail.com>
Date: Mon, 18 Apr 2022 13:15:34 +0200
Subject: [PATCH] Fix outer reference detection in class parents

The case where a class parent was an AppliedType was missing.
Hence, classes that referred to an outer this only via a parent
were mis-categorized.
---
 .../src/dotty/tools/dotc/transform/ExplicitOuter.scala   | 3 ++-
 tests/pos/i14932.scala                                   | 9 +++++++++
 2 files changed, 11 insertions(+), 1 deletion(-)
 create mode 100644 tests/pos/i14932.scala

diff --git a/compiler/src/dotty/tools/dotc/transform/ExplicitOuter.scala b/compiler/src/dotty/tools/dotc/transform/ExplicitOuter.scala
index a7f8421f51d0..0a9798226d76 100644
--- a/compiler/src/dotty/tools/dotc/transform/ExplicitOuter.scala
+++ b/compiler/src/dotty/tools/dotc/transform/ExplicitOuter.scala
@@ -278,7 +278,8 @@ object ExplicitOuter {
           )
       case _ => false
     }
-    def hasOuterPrefix(tp: Type) = tp match {
+    def hasOuterPrefix(tp: Type): Boolean = tp.stripped match {
+      case AppliedType(tycon, _) => hasOuterPrefix(tycon)
       case TypeRef(prefix, _) => isOuterRef(prefix)
       case _ => false
     }
diff --git a/tests/pos/i14932.scala b/tests/pos/i14932.scala
new file mode 100644
index 000000000000..8fff627fc3d7
--- /dev/null
+++ b/tests/pos/i14932.scala
@@ -0,0 +1,9 @@
+trait Core {
+  class Base[T]()
+}
+
+class Module(val core: Core) {
+  object Indirection {
+    class Extension[T]() extends core.Base[T]()
+  }
+}
\ No newline at end of file