Test for eager loading of STI subclasses from htm associations

Signed-off-by: Pratik Naik <pratiknaik@gmail.com>

activerecord/test/cases/associations/join_model_test.rb

@@ -694,6 +694,13 @@ def test_has_many_through_include_returns_false_for_non_matching_record_to_verif
     assert ! david.categories.include?(category)
   end
 
+  def test_has_many_through_goes_through_all_sti_classes
+    sub_sti_post = SubStiPost.create!(:title => 'test', :body => 'test', :author_id => 1)
+    new_comment = sub_sti_post.comments.create(:body => 'test')
+
+    assert_equal [9, 10, new_comment.id], authors(:david).sti_post_comments.map(&:id).sort
+  end
+
   private
     # create dynamic Post models to allow different dependency options
     def find_post_with_dependency(post_id, association, association_name, dependency)

activerecord/test/models/author.rb

@@ -32,6 +32,9 @@ def testing_proxy_target
   has_many :special_posts
   has_many :special_post_comments, :through => :special_posts, :source => :comments
 
+  has_many :sti_posts, :class_name => 'StiPost'
+  has_many :sti_post_comments, :through => :sti_posts, :source => :comments
+
   has_many :special_nonexistant_posts, :class_name => "SpecialPost", :conditions => "posts.body = 'nonexistant'"
   has_many :special_nonexistant_post_comments, :through => :special_nonexistant_posts, :source => :comments, :conditions => "comments.post_id = 0"
   has_many :nonexistant_comments, :through => :posts