From 11a9f7ab9431b0f361e43b4ac2bd6ee44827d88b Mon Sep 17 00:00:00 2001
From: Nobuyoshi Nakada <nobu@ruby-lang.org>
Date: Sat, 17 Aug 2019 00:17:15 +0900
Subject: [PATCH] Search refinement module along nested usings

[Bug #16107]
---
 test/ruby/test_refinement.rb | 28 +++++++++++++++++++
 vm_insnhelper.c              | 54 +++++++++++++++++-------------------
 2 files changed, 54 insertions(+), 28 deletions(-)

diff --git a/test/ruby/test_refinement.rb b/test/ruby/test_refinement.rb
index afb4784d00..87d60e41a4 100644
--- a/test/ruby/test_refinement.rb
+++ b/test/ruby/test_refinement.rb
@@ -2295,6 +2295,34 @@ class TestRefinement < Test::Unit::TestCase
     d
   end
 
+  class RefineInUsing
+    module M1
+      refine RefineInUsing do
+        def foo
+          :ok
+        end
+      end
+    end
+
+    module M2
+      using M1
+      refine RefineInUsing do
+        def call_foo
+	  RefineInUsing.new.foo
+        end
+      end
+    end
+
+    using M2
+    def self.test
+      new.call_foo
+    end
+  end
+
+  def test_refine_in_using
+    assert_equal(:ok, RefineInUsing.test)
+  end
+
   private
 
   def eval_using(mod, s)
diff --git a/vm_insnhelper.c b/vm_insnhelper.c
index 2d765e1e95..d2982afdfa 100644
--- a/vm_insnhelper.c
+++ b/vm_insnhelper.c
@@ -2604,39 +2604,37 @@ vm_call_method_each_type(rb_execution_context_t *ec, rb_control_frame_t *cfp, st
 
       case VM_METHOD_TYPE_REFINED: {
         const rb_cref_t *cref = vm_get_cref(cfp->ep);
-	VALUE refinements = cref ? CREF_REFINEMENTS(cref) : Qnil;
-	VALUE refinement;
-	const rb_callable_method_entry_t *ref_me;
 
-	refinement = find_refinement(refinements, cc->me->owner);
+        for (; cref; cref = CREF_NEXT(cref)) {
+            const rb_callable_method_entry_t *ref_me;
+            VALUE refinements = CREF_REFINEMENTS(cref);
+            VALUE refinement = find_refinement(refinements, cc->me->owner);
+            if (NIL_P(refinement)) continue;
 
-	if (NIL_P(refinement)) {
-	    goto no_refinement_dispatch;
-	}
-	ref_me = rb_callable_method_entry(refinement, ci->mid);
+            ref_me = rb_callable_method_entry(refinement, ci->mid);
 
-	if (ref_me) {
-	    if (cc->call == vm_call_super_method) {
-		const rb_control_frame_t *top_cfp = current_method_entry(ec, cfp);
-		const rb_callable_method_entry_t *top_me = rb_vm_frame_method_entry(top_cfp);
-		if (top_me && rb_method_definition_eq(ref_me->def, top_me->def)) {
-		    goto no_refinement_dispatch;
-		}
-	    }
-            if (cc->me->def->type != VM_METHOD_TYPE_REFINED ||
-                 cc->me->def != ref_me->def) {
-                 cc->me = ref_me;
+            if (ref_me) {
+                if (cc->call == vm_call_super_method) {
+                    const rb_control_frame_t *top_cfp = current_method_entry(ec, cfp);
+                    const rb_callable_method_entry_t *top_me = rb_vm_frame_method_entry(top_cfp);
+                    if (top_me && rb_method_definition_eq(ref_me->def, top_me->def)) {
+                        continue;
+                    }
+                }
+                if (cc->me->def->type != VM_METHOD_TYPE_REFINED ||
+                    cc->me->def != ref_me->def) {
+                    cc->me = ref_me;
+                }
+                if (ref_me->def->type != VM_METHOD_TYPE_REFINED) {
+                    return vm_call_method(ec, cfp, calling, ci, cc);
+                }
             }
-	    if (ref_me->def->type != VM_METHOD_TYPE_REFINED) {
-		return vm_call_method(ec, cfp, calling, ci, cc);
-	    }
-	}
-	else {
-	    cc->me = NULL;
-	    return vm_call_method_nome(ec, cfp, calling, ci, cc);
-	}
+            else {
+                cc->me = NULL;
+                return vm_call_method_nome(ec, cfp, calling, ci, cc);
+            }
+        }
 
-      no_refinement_dispatch:
 	if (cc->me->def->body.refined.orig_me) {
 	    cc->me = refined_method_callable_without_refinement(cc->me);
 	}