vm_method.c: clear cache after refine method

* vm_method.c (rb_add_refined_method_entry): clear cache in the
  refined class since refining a method entry is modifying the class.
  [ruby-core:57079] [Bug #8880]

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@42896 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

ChangeLog

@@ -1,3 +1,9 @@
+Mon Sep  9 16:55:59 2013  Nobuyoshi Nakada  <nobu@ruby-lang.org>
+
+	* vm_method.c (rb_add_refined_method_entry): clear cache in the
+	  refined class since refining a method entry is modifying the class.
+	  [ruby-core:57079] [Bug #8880]
+
 Mon Sep  9 09:14:58 2013  Nobuyoshi Nakada  <nobu@ruby-lang.org>
 
 	* tool/rbinstall.rb (Gem::Specification#initialize): default date to

test/ruby/test_refinement.rb

@@ -982,6 +982,29 @@ class TestRefinement < Test::Unit::TestCase
     RUBY
   end
 
+  def test_refine_after_using
+    assert_separately([], <<-"end;")
+      bug8880 = '[ruby-core:57079] [Bug #8880]'
+      module Test
+        refine(String) do
+        end
+      end
+      using Test
+      def t
+        'Refinements are broken!'.chop!
+      end
+      t
+      module Test
+        refine(String) do
+          def chop!
+            self.sub!(/broken/, 'fine')
+          end
+        end
+      end
+      assert_equal('Refinements are fine!', t, bug8880)
+    end;
+  end
+
   private
 
   def eval_using(mod, s)

vm_method.c

@@ -190,6 +190,7 @@ rb_add_refined_method_entry(VALUE refined_class, ID mid)
 
     if (me) {
 	make_method_entry_refined(me);
+	rb_clear_cache_by_class(refined_class);
     }
     else {
 	rb_add_method(refined_class, mid, VM_METHOD_TYPE_REFINED, 0,