'If the "portable" flag is set, the user can overwrite system
configuration options.'

def test_can_set_options_from_system_config_if_portable(self):

    another_path = tempfile.mkdtemp()
    fake_read_system = (lambda : {'electrum_path': self.electrum_dir})
    fake_read_user = (lambda _: {})
    read_user_dir = (lambda : self.user_dir)
    config = SimpleConfig(options={'portable': True}, read_system_config_function=fake_read_system, read_user_config_function=fake_read_user, read_user_dir_function=read_user_dir)
    config.set_key('electrum_path', another_path)
    self.assertEqual(another_path, config.get('electrum_path'))
