Real-world testing of CakePHP controllers?

Question

I'm writing a new application with CakePHP (just-released 1.2.4), using SimpleTest 1.0.1. I have read the relevant sections of the Cookbook, searched on the Bakery, and read Mark Story's postings on controller testing (the hard way and with mocks).

Unfortunately, none of this talks about real-world testing of non-trivial controllers. Lots of apps put areas of the site behind a login, yet I cannot figure out how to test the simple scenario of:

• guest access to protected page redirects?
• valid credentials sets expected session variables?
• invalid credentials re-displays login page with error message?

The controller and test below do not work as I thought they would. Both assertions fail and I also get a PHP error:

FAILED [NULL] should not be null at [.../app/tests/cases/controllers/users_controller.test.php line 79] .../app/tests/cases/controllers/users_controller.test.php -> UsersControllerTest -> testLogin

FAILED Equal expectation fails as [NULL] does not match [Integer: 1] at [.../app/tests/cases/controllers/users_controller.test.php line 80] .../app/tests/cases/controllers/users_controller.test.php -> UsersControllerTest -> testLogin

ERROR Unexpected PHP error [Undefined index: action] severity [E_NOTICE] in [.../cake/libs/controller/components/auth.php line 266] .../app/tests/cases/controllers/users_controller.test.php -> UsersControllerTest -> testLogin

Here is the controller (baked plus Mark Story's "hard way" testing method):

class UsersController extends AppController
{
  var $name = 'Users';
  var $helpers = array('Html', 'Form');
  var $components = array('Auth');

  function login()
  {
  }

  function logout()
  {
    $this->redirect($this->Auth->logout());
  }

  function index()
  {
    $this->set('users', $this->paginate());
  }

  function view($id = null)
  {
    if (!$id)
    {
      $this->Session->setFlash(__('Invalid User.', true));
      $this->redirect(array('action'=>'index'));
    }
    $this->set('user', $this->User->read(null, $id));
  }

  function add()
  {
    if (!empty($this->data))
    {
      $this->User->create();
      if ($this->User->save($this->data))
      {
        $this->Session->setFlash(__('The User has been saved', true));
        $this->redirect(array('action'=>'index'));
      }
      else
      {
        $this->Session->setFlash(__('The User could not be saved. Please, try again.', true));
      }
    }
  }

  function edit($id = null)
  {
    if (!$id && empty($this->data))
    {
      $this->Session->setFlash(__('Invalid User', true));
      $this->redirect(array('action'=>'index'));
    }
    if (!empty($this->data))
    {
      if ($this->User->save($this->data))
      {
        $this->Session->setFlash(__('The User has been saved', true));
        $this->redirect(array('action'=>'index'));
      }
      else
      {
            $this->Session->setFlash(__('The User could not be saved. Please, try again.', true));
      }
    }
    if (empty($this->data))
    {
      $this->data = $this->User->read(null, $id);
    }
  }

  function delete($id = null)
  {
    if (!$id)
    {
      $this->Session->setFlash(__('Invalid id for User', true));
      $this->redirect(array('action'=>'index'));
    }
    if ($this->User->del($id))
    {
      $this->Session->setFlash(__('User deleted', true));
      $this->redirect(array('action'=>'index'));
    }
  }
}

Here is the test:

/* SVN FILE: $Id$ */
/* UsersController Test cases generated on: 2009-08-05 17:08:03 : 1249507923*/
App::import('Controller', 'Users');

class TestUsers extends UsersController
{
  var $autoRender = false;
  var $redirectUrl;
  var $redirectStatus;
  var $renderedAction;
  var $renderedLayout;
  var $renderedFile;
  var $stopped;

  function redirect($url, $status = null, $exit = true)
  {
    $this->redirectUrl = $url;
    $this->redirectStatus = $status;
  }

  function render($action = null, $layout = null, $file = null)
  {
    $this->renderedAction = $action;
    $this->renderedLayout = (is_null($layout) ? $this->layout : $layout);
    $this->renderedFile = $file;
  }

  function _stop($status = 0)
  {
    $this->stopped = $status;
  }
}

class UsersControllerTest extends CakeTestCase
{
  var $fixtures = array('user');
  var $Users = null;

  function startTest()
  {
    $this->Users = new TestUsers();
    $this->Users->constructClasses();
    $this->Users->Component->initialize($this->Users);
  }

  function prepareForAction()
  {
    $this->Users->beforeFilter();
    $this->Users->Component->startup($this->Users);
  }

  function endTest()
  {
    $this->Users->Session->destroy();
    unset($this->Users);
    ClassRegistry::flush();
  }

  //-----------------------------------------------------------------------

  function testUsersControllerInstance()
  {
    $this->assertTrue(is_a($this->Users, 'UsersController'));
  }

  function testLogin()
  {
    $this->Users->data = array(
      'User' => array(
        'username' => 'admin',
        'password' => 'admin'
      )
    );

    $this->prepareForAction();
    $this->Users->login();

    $this->assertNotNull($this->Users->redirectUrl);
    $this->assertEqual($this->Users->Session->read('Auth.User.id'), 1);
  }
}

Answer 1

The test you have isn't really testing your UsersContoller, you're really testing the AuthComponent. If you want to do this you need to make sure you setup your TestUsersController the same as it would be in your app. In the case of your testLogin you need to set the controller's action and url:

function testLogin()
{
 $this->Users->data = array(
              'User' => array(
                    'username' => 'admin',
                    'password' => 'admin'
                  )
            );

 $this->Users->params['url']['url'] = '/users/login';
 $this->Users->params['action'] = 'login';
 $this->prepareForAction();
 $this->Users->login();

 $this->assertNotNull($this->Users->redirectUrl);
 $this->assertEqual($this->Users->Session->read('Auth.User.id'), 1);
}

Alternately, I would suggest taking another look at Mark's mock objects post and using those methods to write tests for the controller code and mocking the auth component.