Failing test for #6034

railties/test/application/middleware/session_test.rb

@@ -26,5 +26,25 @@ module ApplicationTests
       require "#{app_path}/config/environment"
       assert app.config.session_options[:secure], "Expected session to be marked as secure"
     end
+
+    test "session is not loaded if it's not used" do
+      make_basic_app
+
+      class ::OmgController < ActionController::Base
+        def index
+          if params[:flash]
+            flash[:notice] = "notice"
+          end
+
+          render :nothing => true
+        end
+      end
+
+      get "/?flash=true"
+      get "/"
+
+      assert last_request.env["HTTP_COOKIE"]
+      assert !last_response.headers["Set-Cookie"]
+    end
   end
 end