just return the record from insert_record, use truthiness for comparisons

activerecord/lib/active_record/associations/has_many_through_association.rb

@@ -26,14 +26,14 @@ def size
 
         def insert_record(record, force = true, validate = true)
           if record.new_record?
-            return false unless save_record(record, force, validate)
+            return unless save_record(record, force, validate)
           end
 
           through_association = @owner.send(@reflection.through_reflection.name)
           through_association.create!(construct_join_attributes(record))
 
           update_counter(1)
-          true
+          record
         end
 
       private

activerecord/lib/active_record/autosave_association.rb

@@ -306,6 +306,8 @@ def save_collection_association(reflection)
           records.each do |record|
             next if record.destroyed?
 
+            saved = true
+
             if autosave && record.marked_for_destruction?
               association.destroy(record)
             elsif autosave != false && (@new_record_before_save || record.new_record?)
@@ -318,7 +320,7 @@ def save_collection_association(reflection)
               saved = record.save(:validate => false)
             end
 
-            raise ActiveRecord::Rollback if saved == false
+            raise ActiveRecord::Rollback unless saved
           end
         end