1 files changed, 9 insertions, 0 deletions
diff --git a/activerecord/test/associations/join_model_test.rb b/activerecord/test/associations/join_model_test.rb
index d18c878733..d92a0c760a 100644
--- a/activerecord/test/associations/join_model_test.rb
+++ b/activerecord/test/associations/join_model_test.rb
@@ -457,6 +457,15 @@ class AssociationsJoinModelTest < Test::Unit::TestCase
     assert !author.comments.loaded?
   end
 
+  uses_mocha('has_many_through_collection_size_uses_counter_cache_if_it_exists') do
+    def test_has_many_through_collection_size_uses_counter_cache_if_it_exists
+      author = authors(:david)
+      author.stubs(:read_attribute).with('comments_count').returns(100)
+      assert_equal 100, author.comments.size
+      assert !author.comments.loaded?
+    end
+  end
+
   def test_adding_junk_to_has_many_through_should_raise_type_mismatch
     assert_raise(ActiveRecord::AssociationTypeMismatch) { posts(:thinking).tags << "Uhh what now?" }
   end