Fix #3271.

Building the conditions of a nested through association could
potentially modify the conditions of the through and/or source
association.

This is a Bad Thing.

1 files changed, 6 insertions, 0 deletions

diff --git a/activerecord/test/cases/reflection_test.rb b/activerecord/test/cases/reflection_test.rb
index 69e9fc8d61..4d21822cf5 100644
--- a/activerecord/test/cases/reflection_test.rb
+++ b/activerecord/test/cases/reflection_test.rb
@@ -319,6 +319,12 @@ class ReflectionTest < ActiveRecord::TestCase
     assert_equal "category_id", Post.reflect_on_association(:categorizations).foreign_key.to_s
   end
 
+  def test_through_reflection_conditions_do_not_modify_other_reflections
+    orig_conds = Post.reflect_on_association(:first_blue_tags_2).conditions.inspect
+    Author.reflect_on_association(:misc_post_first_blue_tags_2).conditions
+    assert_equal orig_conds, Post.reflect_on_association(:first_blue_tags_2).conditions.inspect
+  end
+
   private
     def assert_reflection(klass, association, options)
       assert reflection = klass.reflect_on_association(association)