def load(self, requirements_file=None):
        """Load or reload requirements from a requirements.txt file.

        :param requirements_file: if not given, the filename used from
            initialization will be read again.
        """
        if requirements_file is None:
            requirements_file = self.filename
            if requirements_file is None:
                raise ValueError("no filename provided")
        elif isinstance(requirements_file, text_type):
            requirements_file = Path(requirements_file)
        self.clear()
        with requirements_file.open() as f:
            self.loads(f.read())

        if isinstance(requirements_file, (text_type, Path)):
            self.filename = requirements_file
def test_user_login(self):
        c = Client()
        # User points the browser to the landing page
        res = c.post('/', follow=True)

        # the user is not logged in
        self.assertFalse(res.context['user'].is_authenticated)
        # and is redirected to the login page
        self.assertRedirects(res, '/login/')

        # The login page is being rendered by the correct template
        self.assertTemplateUsed(res, 'registration/login.html')

        # asks the user to login using a set of valid credentials
        res = c.post('/login/', data=self.credentials, follow=True)

        # The system acknowledges him
        self.assertTrue(res.context['user'].is_authenticated)

        # and moves him at the dashboard
        self.assertTemplateUsed(res, 'app/dashboard.html')