Add a test for STI on the through where the through is nested, and change the code which support this

4 files changed, 21 insertions, 0 deletions

diff --git a/activerecord/test/cases/associations/nested_through_associations_test.rb b/activerecord/test/cases/associations/nested_through_associations_test.rb
index a4ac69782a..0dd407f342 100644
--- a/activerecord/test/cases/associations/nested_through_associations_test.rb
+++ b/activerecord/test/cases/associations/nested_through_associations_test.rb
@@ -425,6 +425,15 @@ class NestedThroughAssociationsTest < ActiveRecord::TestCase
     assert !scope.where("comments.type" => "SubSpecialComment").empty?
   end
 
+  def test_has_many_through_with_sti_on_nested_through_reflection
+    taggings = posts(:sti_comments).special_comments_ratings_taggings
+    assert_equal [taggings(:special_comment_rating)], taggings
+
+    scope = Post.joins(:special_comments_ratings_taggings).where(:id => posts(:sti_comments).id)
+    assert scope.where("comments.type" => "Comment").empty?
+    assert !scope.where("comments.type" => "SpecialComment").empty?
+  end
+
   def test_nested_has_many_through_writers_should_raise_error
     david = authors(:david)
     subscriber = subscribers(:first)
diff --git a/activerecord/test/fixtures/taggings.yml b/activerecord/test/fixtures/taggings.yml
index a337cce019..d339c12b25 100644
--- a/activerecord/test/fixtures/taggings.yml
+++ b/activerecord/test/fixtures/taggings.yml
@@ -66,3 +66,13 @@ other_by_mary_blue:
   taggable_id: 11
   taggable_type: Post
   comment: first
+
+special_comment_rating:
+  id: 12
+  taggable_id: 2
+  taggable_type: Rating
+
+normal_comment_rating:
+  id: 13
+  taggable_id: 1
+  taggable_type: Rating
diff --git a/activerecord/test/models/post.rb b/activerecord/test/models/post.rb
index b39325f949..c3843fd264 100644
--- a/activerecord/test/models/post.rb
+++ b/activerecord/test/models/post.rb
@@ -50,6 +50,7 @@ class Post < ActiveRecord::Base
   has_many :nonexistant_comments, :class_name => 'Comment', :conditions => 'comments.id < 0'
 
   has_many :special_comments_ratings, :through => :special_comments, :source => :ratings
+  has_many :special_comments_ratings_taggings, :through => :special_comments_ratings, :source => :taggings
 
   has_and_belongs_to_many :categories
   has_and_belongs_to_many :special_categories, :join_table => "categories_posts", :association_foreign_key => 'category_id'
diff --git a/activerecord/test/models/rating.rb b/activerecord/test/models/rating.rb
index 12c4b5affa..25a52c4ad7 100644
--- a/activerecord/test/models/rating.rb
+++ b/activerecord/test/models/rating.rb
@@ -1,3 +1,4 @@
 class Rating < ActiveRecord::Base
   belongs_to :comment
+  has_many :taggings, :as => :taggable
 end