1 files changed, 32 insertions, 0 deletions
diff --git a/activesupport/test/core_ext/module_test.rb b/activesupport/test/core_ext/module_test.rb
index a17438bf4d..085fd6592d 100644
--- a/activesupport/test/core_ext/module_test.rb
+++ b/activesupport/test/core_ext/module_test.rb
@@ -70,7 +70,23 @@ Product = Struct.new(:name) do
   end
 end
 
+module ExtraMissing
+  def method_missing(sym, *args)
+    if sym == :extra_missing
+      42
+    else
+      super
+    end
+  end
+
+  def respond_to_missing?(sym, priv = false)
+    sym == :extra_missing || super
+  end
+end
+
 DecoratedTester = Struct.new(:client) do
+  include ExtraMissing
+
   delegate_missing_to :client
 end
 
@@ -356,6 +372,22 @@ class ModuleTest < ActiveSupport::TestCase
     assert_match(/undefined method `my_fake_method' for/, e.message)
   end
 
+  def test_delegate_to_missing_affects_respond_to
+    assert DecoratedTester.new(@david).respond_to?(:name)
+    assert_not DecoratedTester.new(@david).respond_to?(:private_name)
+    assert_not DecoratedTester.new(@david).respond_to?(:my_fake_method)
+
+    assert DecoratedTester.new(@david).respond_to?(:name, true)
+    assert_not DecoratedTester.new(@david).respond_to?(:private_name, true)
+    assert_not DecoratedTester.new(@david).respond_to?(:my_fake_method, true)
+  end
+
+  def test_delegate_to_missing_respects_superclass_missing
+    assert_equal 42, DecoratedTester.new(@david).extra_missing
+
+    assert_respond_to DecoratedTester.new(@david), :extra_missing
+  end
+
   def test_delegate_with_case
     event = Event.new(Tester.new)
     assert_equal 1, event.foo