From 0bc3a4325bd32136b52deb213a2429cfc0445561 Mon Sep 17 00:00:00 2001
From: Joel Meador <joel@expectedbehavior.com>
Date: Sun, 11 Apr 2010 02:32:14 -0400
Subject: [PATCH] self referencing models don't cause stack overflows on save [#1924 state:resolved]

---
 .../lib/active_record/autosave_association.rb      |    3 ++-
 .../cases/associations/self_association_test.rb    |   12 ++++++++++++
 activerecord/test/models/synonym.rb                |    3 +++
 activerecord/test/schema/schema.rb                 |    4 ++++
 4 files changed, 21 insertions(+), 1 deletions(-)
 create mode 100644 activerecord/test/cases/associations/self_association_test.rb
 create mode 100644 activerecord/test/models/synonym.rb

diff --git a/activerecord/lib/active_record/autosave_association.rb b/activerecord/lib/active_record/autosave_association.rb
index 8d40eb5..16d90a7 100644
--- a/activerecord/lib/active_record/autosave_association.rb
+++ b/activerecord/lib/active_record/autosave_association.rb
@@ -1,3 +1,4 @@
+# -*- coding: utf-8 -*-
 module ActiveRecord
   # AutosaveAssociation is a module that takes care of automatically saving
   # your associations when the parent is saved. In addition to saving, it
@@ -355,7 +356,7 @@ module ActiveRecord
         if autosave && association.marked_for_destruction?
           association.destroy
         elsif autosave != false
-          saved = association.save(!autosave) if association.new_record? || autosave
+          saved = association.save(!autosave) if (association.new_record? && self != association) || autosave
 
           if association.updated?
             association_id = association.send(reflection.options[:primary_key] || :id)
diff --git a/activerecord/test/cases/associations/self_association_test.rb b/activerecord/test/cases/associations/self_association_test.rb
new file mode 100644
index 0000000..5e907fd
--- /dev/null
+++ b/activerecord/test/cases/associations/self_association_test.rb
@@ -0,0 +1,12 @@
+require "cases/helper"
+require "models/synonym"
+
+class SelfAssociationTest < ActiveRecord::TestCase
+  def test_save_record_that_belongs_to_itself_doesnt_overflow_stack
+    synonym = Synonym.new
+    synonym.synonym = synonym
+    assert_nothing_raised{
+      synonym.save!
+    }
+  end
+end
diff --git a/activerecord/test/models/synonym.rb b/activerecord/test/models/synonym.rb
new file mode 100644
index 0000000..e4044a9
--- /dev/null
+++ b/activerecord/test/models/synonym.rb
@@ -0,0 +1,3 @@
+class Synonym < ActiveRecord::Base
+  belongs_to :synonym
+end
diff --git a/activerecord/test/schema/schema.rb b/activerecord/test/schema/schema.rb
index c8e652a..37d5ba1 100644
--- a/activerecord/test/schema/schema.rb
+++ b/activerecord/test/schema/schema.rb
@@ -430,6 +430,10 @@ ActiveRecord::Schema.define do
     t.integer :book_id
   end
 
+  create_table :synonyms, :force => true do |t|
+    t.integer :synonym_id
+  end
+  
   create_table :tasks, :force => true do |t|
     t.datetime :starting
     t.datetime :ending
-- 
1.6.6