Check if Test::Unit is defined before adding backtrace filter.

1 files changed, 17 insertions, 0 deletions

diff --git a/railties/test/application/test_test.rb b/railties/test/application/test_test.rb
index 37175783d8..de316a6fd0 100644
--- a/railties/test/application/test_test.rb
+++ b/railties/test/application/test_test.rb
@@ -23,6 +23,23 @@ module ApplicationTests
       run_test 'unit/foo_test.rb'
     end
 
+    # Run just in Ruby < 1.9
+    if defined?(Test::Unit::Util::BacktraceFilter)
+      test "adds backtrace cleaner" do
+        app_file 'test/unit/backtrace_test.rb', <<-RUBY
+          require 'test_helper'
+
+          class FooTest < ActiveSupport::TestCase
+            def test_truth
+              assert Test::Unit::Util::BacktraceFilter.ancestors.include?(Rails::BacktraceFilterForTestUnit)
+            end
+          end
+        RUBY
+
+        run_test 'unit/backtrace_test.rb'
+      end
+    end
+
     test "integration test" do
       controller 'posts', <<-RUBY
         class PostsController < ActionController::Base