Merge branch 'master' into nested_has_many_through

Conflicts:
	activerecord/CHANGELOG
	activerecord/lib/active_record/associations/class_methods/join_dependency.rb
	activerecord/lib/active_record/associations/class_methods/join_dependency/join_association.rb
	activerecord/lib/active_record/associations/has_many_through_association.rb

1 files changed, 41 insertions, 0 deletions

diff --git a/activerecord/lib/active_record/associations.rb b/activerecord/lib/active_record/associations.rb
index fe22fa7ca2..9544fdcb39 100644
--- a/activerecord/lib/active_record/associations.rb
+++ b/activerecord/lib/active_record/associations.rb
@@ -1266,12 +1266,14 @@ module ActiveRecord
 
         if reflection.options[:polymorphic]
           association_accessor_methods(reflection, BelongsToPolymorphicAssociation)
+          association_foreign_type_setter_method(reflection)
         else
           association_accessor_methods(reflection, BelongsToAssociation)
           association_constructor_method(:build,  reflection, BelongsToAssociation)
           association_constructor_method(:create, reflection, BelongsToAssociation)
         end
 
+        association_foreign_key_setter_method(reflection)
         add_counter_cache_callbacks(reflection)          if options[:counter_cache]
         add_touch_callbacks(reflection, options[:touch]) if options[:touch]
 
@@ -1598,6 +1600,45 @@ module ActiveRecord
           end
         end
 
+        def association_foreign_key_setter_method(reflection)
+          setters = reflect_on_all_associations(:belongs_to).map do |belongs_to_reflection|
+            if belongs_to_reflection.primary_key_name == reflection.primary_key_name
+              "association_instance_set(:#{belongs_to_reflection.name}, nil);"
+            end
+          end.compact.join
+
+          if method_defined?(:"#{reflection.primary_key_name}=")
+            undef_method :"#{reflection.primary_key_name}="
+          end
+
+          class_eval <<-FILE, __FILE__, __LINE__ + 1
+            def #{reflection.primary_key_name}=(new_id)
+              write_attribute :#{reflection.primary_key_name}, new_id
+              if #{reflection.primary_key_name}_changed?
+                #{ setters }
+              end
+            end
+          FILE
+        end
+
+        def association_foreign_type_setter_method(reflection)
+          setters = reflect_on_all_associations(:belongs_to).map do |belongs_to_reflection|
+            if belongs_to_reflection.options[:foreign_type] == reflection.options[:foreign_type]
+              "association_instance_set(:#{belongs_to_reflection.name}, nil);"
+            end
+          end.compact.join
+
+          field = reflection.options[:foreign_type]
+          class_eval <<-FILE, __FILE__, __LINE__ + 1
+            def #{field}=(new_id)
+              write_attribute :#{field}, new_id
+              if #{field}_changed?
+                #{ setters }
+              end
+            end
+          FILE
+        end
+
         def add_counter_cache_callbacks(reflection)
           cache_column = reflection.counter_cache_column