2 files changed, 14 insertions, 4 deletions
diff --git a/activesupport/lib/active_support/concern.rb b/activesupport/lib/active_support/concern.rb
index 154f8807f7..a09a2420b3 100644
--- a/activesupport/lib/active_support/concern.rb
+++ b/activesupport/lib/active_support/concern.rb
@@ -7,6 +7,7 @@ module ActiveSupport
     def append_features(base)
       if super
         base.extend const_get("ClassMethods") if const_defined?("ClassMethods")
+        base.send :include, const_get("InstanceMethods") if const_defined?("InstanceMethods")
         base.class_eval(&@_included_block) if instance_variable_defined?("@_included_block")
       end
     end
diff --git a/activesupport/test/concern_test.rb b/activesupport/test/concern_test.rb
index 22f7ec2064..40fcb7c57f 100644
--- a/activesupport/test/concern_test.rb
+++ b/activesupport/test/concern_test.rb
@@ -19,6 +19,9 @@ class ConcernTest < Test::Unit::TestCase
       end
     end
 
+    module InstanceMethods
+    end
+
     included do
       self.included_ran = true
     end
@@ -55,11 +58,11 @@ class ConcernTest < Test::Unit::TestCase
   def test_module_is_included_normally
     @klass.send(:include, Baz)
     assert_equal "baz", @klass.new.baz
-    assert_equal ConcernTest::Baz, @klass.included_modules[0]
+    assert @klass.included_modules.include?(ConcernTest::Baz)
 
     @klass.send(:include, Baz)
     assert_equal "baz", @klass.new.baz
-    assert_equal ConcernTest::Baz, @klass.included_modules[0]
+    assert @klass.included_modules.include?(ConcernTest::Baz)
   end
 
   def test_class_methods_are_extended
@@ -68,6 +71,12 @@ class ConcernTest < Test::Unit::TestCase
     assert_equal ConcernTest::Baz::ClassMethods, (class << @klass; self.included_modules; end)[0]
   end
 
+  def test_instance_methods_are_included
+    @klass.send(:include, Baz)
+    assert_equal "baz", @klass.new.baz
+    assert @klass.included_modules.include?(ConcernTest::Baz::InstanceMethods)
+  end
+
   def test_included_block_is_ran
     @klass.send(:include, Baz)
     assert_equal true, @klass.included_ran
@@ -78,11 +87,11 @@ class ConcernTest < Test::Unit::TestCase
     assert_equal "bar", @klass.new.bar
     assert_equal "bar+baz", @klass.new.baz
     assert_equal "baz", @klass.baz
-    assert_equal [ConcernTest::Bar, ConcernTest::Baz], @klass.included_modules[0..1]
+    assert @klass.included_modules.include?(ConcernTest::Bar)
   end
 
   def test_depends_on_with_multiple_modules
     @klass.send(:include, Foo)
-    assert_equal [ConcernTest::Foo, ConcernTest::Bar, ConcernTest::Baz], @klass.included_modules[0..2]
+    assert_equal [ConcernTest::Foo, ConcernTest::Bar, ConcernTest::Baz::InstanceMethods, ConcernTest::Baz], @klass.included_modules[0..3]
   end
 end