1 files changed, 18 insertions, 1 deletions
diff --git a/railties/lib/rails/generators/testing/behaviour.rb b/railties/lib/rails/generators/testing/behaviour.rb
index 7576eba6e0..fd2ea274e1 100644
--- a/railties/lib/rails/generators/testing/behaviour.rb
+++ b/railties/lib/rails/generators/testing/behaviour.rb
@@ -50,7 +50,7 @@ module Rails
         #   class AppGeneratorTest < Rails::Generators::TestCase
         #     tests AppGenerator
         #     destination File.expand_path("../tmp", File.dirname(__FILE__))
-        #     teardown :cleanup_destination_root
+        #     setup :prepare_destination
         #
         #     test "database.yml is not created when skipping Active Record" do
         #       run_generator %w(myapp --skip-active-record)
@@ -100,6 +100,23 @@ module Rails
             dirname, file_name = File.dirname(absolute), File.basename(absolute).sub(/\.rb$/, '')
             Dir.glob("#{dirname}/[0-9]*_*.rb").grep(/\d+_#{file_name}.rb$/).first
           end
+
+          def capture(stream)
+            stream = stream.to_s
+            captured_stream = Tempfile.new(stream)
+            stream_io = eval("$#{stream}")
+            origin_stream = stream_io.dup
+            stream_io.reopen(captured_stream)
+
+            yield
+
+            stream_io.rewind
+            return captured_stream.read
+          ensure
+            captured_stream.close
+            captured_stream.unlink
+            stream_io.reopen(origin_stream)
+          end
       end
     end
   end