AS::StringInquirer#respond_to_missing? should fallback to super

in case String or any other ancestor class' respond_to_missing? was defined.

3 files changed, 19 insertions, 3 deletions

diff --git a/activesupport/CHANGELOG.md b/activesupport/CHANGELOG.md
index aefc94e0d9..0bb6b2466c 100644
--- a/activesupport/CHANGELOG.md
+++ b/activesupport/CHANGELOG.md
@@ -1,5 +1,5 @@
-*   Fixed a bug that `ArrayInquirer#respond_to_missing?` does not fallback to
-    `Array#respond_to_missing?`.
+*   Fixed bugs that `StringInquirer#respond_to_missing?` and
+    `ArrayInquirer#respond_to_missing?` do not fallback to `super`.
 
     *Akira Matsuda*
 
diff --git a/activesupport/lib/active_support/string_inquirer.rb b/activesupport/lib/active_support/string_inquirer.rb
index 09e1cbb28d..90eac89c9e 100644
--- a/activesupport/lib/active_support/string_inquirer.rb
+++ b/activesupport/lib/active_support/string_inquirer.rb
@@ -18,7 +18,7 @@ module ActiveSupport
     private
 
       def respond_to_missing?(method_name, include_private = false)
-        method_name[-1] == "?"
+        (method_name[-1] == "?") || super
       end
 
       def method_missing(method_name, *arguments)
diff --git a/activesupport/test/string_inquirer_test.rb b/activesupport/test/string_inquirer_test.rb
index d41e4d6800..2a5e7d02e4 100644
--- a/activesupport/test/string_inquirer_test.rb
+++ b/activesupport/test/string_inquirer_test.rb
@@ -20,4 +20,20 @@ class StringInquirerTest < ActiveSupport::TestCase
   def test_respond_to
     assert_respond_to @string_inquirer, :development?
   end
+
+  def test_respond_to_fallback_to_string_respond_to
+    String.class_eval do
+      def respond_to_missing?(name, include_private = false)
+        (name == :bar) || super
+      end
+    end
+    str = ActiveSupport::StringInquirer.new("hello")
+
+    assert_respond_to str, :are_you_ready?
+    assert_respond_to str, :bar
+    assert_not_respond_to str, :nope
+
+  ensure
+    String.send :undef_method, :respond_to_missing?
+  end
 end