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

1 files changed, 23 insertions, 0 deletions

diff --git a/test/ruby/test_refinement.rb b/test/ruby/test_refinement.rb
index 8efbb1a85a..02193ae615 100644
--- a/test/ruby/test_refinement.rb
+++ b/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)