diff --git a/test/test_filters.rb b/test/test_filters.rb
index 9537377a..e56a88ce 100644
--- a/test/test_filters.rb
+++ b/test/test_filters.rb
@@ -1,3 +1,5 @@
+# coding: utf-8
+
 require 'helper'
 
 class TestFilters < Test::Unit::TestCase