diff --git a/test/unit/active_model/serializer/config_test.rb b/test/unit/active_model/serializer/config_test.rb
index 481a3f15..0a88cfb7 100644
--- a/test/unit/active_model/serializer/config_test.rb
+++ b/test/unit/active_model/serializer/config_test.rb
@@ -58,7 +58,7 @@ module ActiveModel
         def test_setup_acessor_when_nil
           assert_nil CONFIG.foo
           CONFIG.foo = 1
-          assert 1, CONFIG.foo
+          assert_equal 1, CONFIG.foo
           assert_nil CONFIG.bar
         end
       end