Fix #3129: Sharpen criterion for localRefs in inlining

Author: odersky

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

@@ -120,7 +120,8 @@ object Inliner {
 
             // The types that are local to the inlined method, and that therefore have
             // to be abstracted out in the accessor, which is external to the inlined method
-            val localRefs = qualType.namedPartsWith(_.symbol.isContainedIn(inlineMethod)).toList
+            val localRefs = qualType.namedPartsWith(ref =>
+              ref.isType && ref.symbol.isContainedIn(inlineMethod)).toList
 
             // Abstract accessed type over local refs
             def abstractQualType(mtpe: Type): Type =

tests/pos/i3129.scala

@@ -0,0 +1,22 @@
+object companions2 {
+  inline def foo() = {
+    class C {
+      println(C.p)
+    }
+
+    object C {
+      private val p = 1
+    }
+  }
+}
+
+class A {
+  val b = new B
+
+  class B {
+    private def getAncestor2(p: A): A = p
+    private inline def getAncestor(p: A): A = {
+      p.b.getAncestor(p)
+    }
+  }
+}