Add has_one :through support, finally. Closes #4756 [thechrisoshow]

git-svn-id: http://svn-commit.rubyonrails.org/rails/trunk@9067 5ecf4fe2-1ee6-0310-87b1-e25e094e27de

1 files changed, 28 insertions, 0 deletions

diff --git a/activerecord/lib/active_record/associations/has_one_through_association.rb b/activerecord/lib/active_record/associations/has_one_through_association.rb
new file mode 100644
index 0000000000..ecf9d8208d
--- /dev/null
+++ b/activerecord/lib/active_record/associations/has_one_through_association.rb
@@ -0,0 +1,28 @@
+module ActiveRecord
+  module Associations
+    class HasOneThroughAssociation < ActiveRecord::Associations::HasManyThroughAssociation
+      
+      def create_through_record(new_value) #nodoc:
+        klass = @reflection.through_reflection.klass
+
+        current_object = @owner.send(@reflection.through_reflection.name)
+        
+        if current_object
+          klass.destroy(current_object)
+          @owner.clear_association_cache
+        end
+        
+        @owner.send(@reflection.through_reflection.name,  klass.send(:create, construct_join_attributes(new_value)))
+      end
+      
+    private
+      def find(*args)
+        super(args.merge(:limit => 1))
+      end
+    
+      def find_target
+        super.first
+      end        
+    end        
+  end
+end