1 files changed, 4 insertions, 0 deletions
diff --git a/activesupport/test/memoizable_test.rb b/activesupport/test/memoizable_test.rb
index 1b6cec2b2f..fc24a2942d 100644
--- a/activesupport/test/memoizable_test.rb
+++ b/activesupport/test/memoizable_test.rb
@@ -41,5 +41,9 @@ uses_mocha 'Memoizable' do
       person.freeze
       assert_equal nil, person.age
     end
+
+    def test_double_memoization
+      assert_raise(RuntimeError) { Person.memoize :name }
+    end
   end
 end