From a70bb8889b3130d72ec5a1f0ce92f386000a60da Mon Sep 17 00:00:00 2001
From: charliesome <charliesome@b2dd03c8-39d4-4d8f-98ff-823fe69b080e>
Date: Mon, 17 Dec 2012 09:49:00 +0000
Subject: [PATCH] * class.c (rewrite_cref_stack, clone_method): rewrite a
 method's cref   stack when cloning into a new class to allow lexical const
 lookup to   work as expected [ruby-core:47834] [Bug #7107] *
 test/ruby/test_class.rb (class TestClass): related test

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@38423 b2dd03c8-39d4-4d8f-98ff-823fe69b080e
---
 ChangeLog               |  7 +++++++
 class.c                 | 18 ++++++++++++++++++
 test/ruby/test_class.rb | 14 ++++++++++++++
 3 files changed, 39 insertions(+)

diff --git a/ChangeLog b/ChangeLog
index abaf992047..994ed22229 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,10 @@
+Mon Dec 17 18:03:34 2012  Charlie Somerville  <charlie@charliesomerville.com>
+
+	* class.c (rewrite_cref_stack, clone_method): rewrite a method's cref
+	  stack when cloning into a new class to allow lexical const lookup to
+	  work as expected [ruby-core:47834] [Bug #7107]
+	* test/ruby/test_class.rb (class TestClass): related test
+
 Mon Dec 17 13:56:55 2012  KOSAKI Motohiro  <kosaki.motohiro@gmail.com>
 
 	* io.c (io_flush_buffer_sync2): avoid to return 0. because
diff --git a/class.c b/class.c
index 43862d6d4d..1fc7172d27 100644
--- a/class.c
+++ b/class.c
@@ -121,6 +121,23 @@ rb_class_new(VALUE super)
     return rb_class_boot(super);
 }
 
+static NODE*
+rewrite_cref_stack(NODE *node, VALUE old_klass, VALUE new_klass)
+{
+    NODE *new_node;
+    if (!node) {
+	return NULL;
+    }
+    if (node->nd_clss == old_klass) {
+	new_node = NEW_CREF(new_klass);
+	new_node->nd_next = node->nd_next;
+    } else {
+	new_node = NEW_CREF(node->nd_clss);
+	new_node->nd_next = rewrite_cref_stack(node->nd_next, old_klass, new_klass);
+    }
+    return new_node;
+}
+
 static void
 clone_method(VALUE klass, ID mid, const rb_method_entry_t *me)
 {
@@ -129,6 +146,7 @@ clone_method(VALUE klass, ID mid, const rb_method_entry_t *me)
 	rb_iseq_t *iseq;
 	newiseqval = rb_iseq_clone(me->def->body.iseq->self, klass);
 	GetISeqPtr(newiseqval, iseq);
+	iseq->cref_stack = rewrite_cref_stack(me->def->body.iseq->cref_stack, me->klass, klass);
 	rb_add_method(klass, mid, VM_METHOD_TYPE_ISEQ, iseq, me->flag);
 	RB_GC_GUARD(newiseqval);
     }
diff --git a/test/ruby/test_class.rb b/test/ruby/test_class.rb
index e3047ccd5f..0ac29b3cf4 100644
--- a/test/ruby/test_class.rb
+++ b/test/ruby/test_class.rb
@@ -285,4 +285,18 @@ class TestClass < Test::Unit::TestCase
       p A.superclass
     RUBY
   end
+
+  module M
+    C = 1
+
+    def self.m
+      C
+    end
+  end
+
+  def test_constant_access_from_method_in_cloned_module # [ruby-core:47834]
+    m = M.dup
+    assert_equal 1, m::C
+    assert_equal 1, m.m
+  end
 end