From e5bcc3b32b4c651d5d48eb3338eaf2308197dbf9 Mon Sep 17 00:00:00 2001
From: Tanel Suurhans <tanel.suurhans@perfectline.ee>
Date: Fri, 30 Apr 2010 15:57:25 +0300
Subject: [PATCH] Proposed fix for issue related and described in ticket #974

---
 activerecord/lib/active_record/associations.rb     |   12 +++++++-----
 .../associations/has_one_associations_test.rb      |   14 ++++++++++++++
 activerecord/test/models/member.rb                 |    1 +
 3 files changed, 22 insertions(+), 5 deletions(-)

diff --git a/activerecord/lib/active_record/associations.rb b/activerecord/lib/active_record/associations.rb
index 6c64210..8a687b1 100755
--- a/activerecord/lib/active_record/associations.rb
+++ b/activerecord/lib/active_record/associations.rb
@@ -1561,12 +1561,14 @@ module ActiveRecord
                   end
                 eoruby
               when :nullify
-                class_eval <<-eoruby, __FILE__, __LINE__ + 1
-                  def #{method_name}
-                    association = #{reflection.name}
-                    association.update_attribute(#{reflection.primary_key_name.inspect}, nil) if association
+                define_method(method_name) do
+                  association = send(reflection.name)
+                  if reflection.options.has_key?(:as)
+                    association.update_attribute(reflection.options[:as], nil) if association
+                  else
+                    association.update_attribute(reflection.primary_key_name, nil) if association
                   end
-                eoruby
+                end
               when :restrict
                 method_name = "has_one_dependent_restrict_for_#{reflection.name}".to_sym
                 define_method(method_name) do
diff --git a/activerecord/test/cases/associations/has_one_associations_test.rb b/activerecord/test/cases/associations/has_one_associations_test.rb
index 8f55409..02ab0a6 100644
--- a/activerecord/test/cases/associations/has_one_associations_test.rb
+++ b/activerecord/test/cases/associations/has_one_associations_test.rb
@@ -2,6 +2,8 @@ require "cases/helper"
 require 'models/developer'
 require 'models/project'
 require 'models/company'
+require 'models/member'
+require 'models/sponsor'
 
 class HasOneAssociationsTest < ActiveRecord::TestCase
   fixtures :accounts, :companies, :developers, :projects, :developers_projects
@@ -326,4 +328,16 @@ class HasOneAssociationsTest < ActiveRecord::TestCase
     assert       !account.new_record?
     assert_equal 500, account.credit_limit
   end
+
+  def test_nullify_foreign_type_on_destroy_for_polymorphic_has_one
+    sponsor = Sponsor.create
+    member = Member.new
+    member.supporter = sponsor
+    member.save
+    member.destroy
+
+    assert_nil sponsor.sponsorable
+    assert_nil sponsor.sponsorable_id
+    assert_nil sponsor.sponsorable_type
+  end
 end
diff --git a/activerecord/test/models/member.rb b/activerecord/test/models/member.rb
index 255fb56..34c2c4a 100644
--- a/activerecord/test/models/member.rb
+++ b/activerecord/test/models/member.rb
@@ -5,6 +5,7 @@ class Member < ActiveRecord::Base
   has_one :club, :through => :current_membership
   has_one :favourite_club, :through => :memberships, :conditions => ["memberships.favourite = ?", true], :source => :club
   has_one :sponsor, :as => :sponsorable
+  has_one :supporter, :class_name => "Sponsor", :as => :sponsorable, :dependent => :nullify
   has_one :sponsor_club, :through => :sponsor
   has_one :member_detail
   has_one :organization, :through => :member_detail
-- 
1.7.0.5