node.js - Using supertest to check didFlash after a redirect -

i'm trying test happens when user destroy callback receives error user controller. when destroy receives error, following:

flash('error', 'can not destroy user'); redirect(path_to.users); 

this test far:

it('should fail on delete /users/:id if destroy receives error', function (done) {     var user = app.models.user;     var user = new userstub();      user.find = sinon.spy(function (id, callback) {         callback(null, user);     });      user.destroy = sinon.spy(function (callback) {         callback(new error());     });      request(app)         .del('/users/55')         .end(function (err, res) {             res.header.location.should.include('/users');             app.didflash('error').should.be.true;              done();         }); }); 

i've seen this question , res.header.. portion works expected. however, i'm still confused on how can test flash happens after redirect.

i ended changing users_controller use following code destroy callback (the redirect having other issues):

if (error) {     flash('error', 'can not destroy user'); } else {     flash('info', 'user removed'); } send(302, "'" + pathto.users + "'"); 

the init.js file used mocha.js has few pieces in when initializing app object (some irrelevant code omitted):

global.getapp = function(done) {     var app = require('compound').createserver();      app.renderedviews = [];     app.flashedmessages = {};      app._render = app.render;     app.render = function (viewname, opts, fn) {         app.renderedviews.push(viewname);          // deep-copy flash messages         var flashes = opts.request.session.flash;         for(var type in flashes) {             app.flashedmessages[type] = [];             for(var in flashes[type]) {                 app.flashedmessages[type].push(flashes[type][i]);             }         }          return app._render.apply(this, arguments);     };      app.use(function (req, res, next) {         app._request = req;         next();     });      app.didflash = function (type) {         var flashes = app._request.session.flash;                 return !!(app.flashedmessages[type] || (flashes && flashes[type]));      };      return app; }; 

the original way of checking didflash limited rendering, checks if flash message created before redirect or send.