Merge branch 'master' into wip_abstract_controller

Conflicts:
	actionpack/lib/action_controller/abstract/callbacks.rb
	actionpack/lib/action_controller/abstract/renderer.rb
	actionpack/lib/action_controller/base/base.rb
	actionpack/lib/action_controller/dispatch/dispatcher.rb
	actionpack/lib/action_controller/routing/route_set.rb
	actionpack/lib/action_controller/testing/process.rb
	actionpack/test/abstract_controller/layouts_test.rb
	actionpack/test/controller/filters_test.rb
	actionpack/test/controller/helper_test.rb
	actionpack/test/controller/render_test.rb
	actionpack/test/new_base/test_helper.rb

1 files changed, 21 insertions, 0 deletions

diff --git a/activerecord/lib/active_record/reflection.rb b/activerecord/lib/active_record/reflection.rb
index 2d4c1d5507..ec0175497d 100644
--- a/activerecord/lib/active_record/reflection.rb
+++ b/activerecord/lib/active_record/reflection.rb
@@ -212,6 +212,13 @@ module ActiveRecord
       end
 
       def check_validity!
+        check_validity_of_inverse!
+      end
+
+      def check_validity_of_inverse!
+        if has_inverse? && inverse_of.nil?
+          raise InverseOfAssociationNotFoundError.new(self)
+        end
       end
 
       def through_reflection
@@ -225,6 +232,18 @@ module ActiveRecord
         nil
       end
 
+      def has_inverse?
+        !@options[:inverse_of].nil?
+      end
+
+      def inverse_of
+        if has_inverse?
+          @inverse_of ||= klass.reflect_on_association(options[:inverse_of])
+        else
+          nil
+        end
+      end
+
       private
         def derive_class_name
           class_name = name.to_s.camelize
@@ -300,6 +319,8 @@ module ActiveRecord
         unless [:belongs_to, :has_many].include?(source_reflection.macro) && source_reflection.options[:through].nil?
           raise HasManyThroughSourceAssociationMacroError.new(self)
         end
+
+        check_validity_of_inverse!
       end
 
       def through_reflection_primary_key