these are not real developer objects, so counting them doesn't make

sense.  Let's load the object to ensure it's an array and count the
array.

activerecord/test/cases/associations/has_and_belongs_to_many_associations_test.rb

@@ -651,7 +651,7 @@ def test_find_scoped_grouped
   end
 
   def test_find_scoped_grouped_having
-    assert_equal 2, projects(:active_record).well_payed_salary_groups.size
+    assert_equal 2, projects(:active_record).well_payed_salary_groups.to_a.size
     assert projects(:active_record).well_payed_salary_groups.all? { |g| g.salary > 10000 }
   end