public function testLoginCorrect()
 {
     $model = new LoginForm(['username' => 'demo', 'password' => 'demo']);
     $this->specify('user should be able to login with correct credentials', function () use($model) {
         expect('model should login user', $model->login())->true();
         expect('error message should not be set', $model->errors)->hasntKey('password');
         expect('user should be logged in', Yii::$app->user->isGuest)->false();
     });
 }
 public function actionLogin()
 {
     if (!\Yii::$app->user->isGuest) {
         return $this->goHome();
     }
     $model = new LoginForm();
     if ($model->load(Yii::$app->request->post()) && $model->login()) {
         return $this->goBack();
     } else {
         return $this->render('login', ['model' => $model]);
     }
 }