How to Persist a request (with cookies, ie sessions) Like super-agent

To access some urls in application, one must login first. I must go back to use super-agent to unit test these urls. Can supertest do thing like this?

server = require './testServer'
request = require 'superagent'

r = request.agent()
server.start 3002

fakeUser = 
  username:'tj',
  password:'foobar'

describe 'after login', ->
      beforeEach (done)  ->
        r
          .post("http://localhost:3002/login") 
          .send(fakeUser) 
          .end (err, res) ->
            assert res.statusCode is 200
            done()

      it 'can show restricted page', (done) ->
         r
          .get("http://localhost:3002/restricted")
          .end (err, res) ->
             assert.include res.text,'Wahoo!'
             assert res.statusCode is 200
             done()

[jinwyp]

For the records, full example for @alsotang suggest: You don’t need do anything more with the agent.

var supertest = require('supertest');
var agent     = supertest.agent('localhost/api');

describe('Login', function () {
  it('should login superadmin', function(done) {
    agent
      .post('/login')
      .type('form')
      .send({ email: 'email' })
      .send({ password: 'password' })
      .expect(302)
      .expect('Location', '/')
      .expect('set-cookie', /connect.sid/)
      .end(function(err, res) {
        if (err) return done(err);
        // agent.saveCookies(res); don‘t need this line 
        return done();
      });
  };


it('get user info', function(done) {
// don't need do anything with cookies, agent will  attached cookies automatically based on login above
    agent
      .get('/userinfo')
      .expect(200)
      .end(function(err, res) {
        if (err) return done(err);
        return done();
      });
  };
});

[rafaelgou]

For the records, full example for @alsotang suggest:

(this is a login form, not an API request)

var supertest = require('supertest');
var app       = require('../path_to_my/app')
var agent     = supertest.agent(app);

describe('Login', function () {
  it('should login superadmin', function(done) {
    agent
      .post('/login')
      .type('form')
      .send({ email: 'email' })
      .send({ password: 'password' })
      .expect(302)
      .expect('Location', '/')
      .expect('set-cookie', /connect.sid/)
      .end(function(err, res) {
        if (err) return done(err);
        agent.saveCookies(res);
        return done();
      });
  };
});