1 files changed, 6 insertions, 0 deletions
diff --git a/activesupport/test/core_ext/string_ext_test.rb b/activesupport/test/core_ext/string_ext_test.rb
index fe5ce276c5..b086c957fe 100644
--- a/activesupport/test/core_ext/string_ext_test.rb
+++ b/activesupport/test/core_ext/string_ext_test.rb
@@ -226,6 +226,12 @@ class CoreExtStringMultibyteTest < Test::Unit::TestCase
     def test_core_ext_adds_chars
       assert UNICODE_STRING.respond_to?(:chars)
     end
+
+    def test_chars_warns_about_deprecation
+      assert_deprecated("String#chars") do
+        ''.chars
+      end
+    end
   end
 
   if RUBY_VERSION < '1.9'