1 files changed, 8 insertions, 0 deletions
diff --git a/railties/lib/rails/test_unit/railtie.rb b/railties/lib/rails/test_unit/railtie.rb
index ec91673e40..746120e6a1 100644
--- a/railties/lib/rails/test_unit/railtie.rb
+++ b/railties/lib/rails/test_unit/railtie.rb
@@ -1,3 +1,5 @@
+require "rails/test_unit/line_filtering"
+
 if defined?(Rake.application) && Rake.application.top_level_tasks.grep(/^(default$|test(:|$))/).any?
   ENV["RAILS_ENV"] ||= "test"
 end
@@ -11,6 +13,12 @@ module Rails
       c.integration_tool :test_unit
     end
 
+    initializer "test_unit.line_filtering" do
+      ActiveSupport.on_load(:active_support_test_case) {
+        ActiveSupport::TestCase.extend Rails::LineFiltering
+      }
+    end
+
     rake_tasks do
       load "rails/test_unit/testing.rake"
     end