Mock API请求Xcode 7快速自动UI测试

Is there a way to mock requests when writing automated UI tests in Swift 2.0. As far as I am aware the UI tests should be independent of other functionality. Is there a way to mock the response from server requests in order to test the behaviour of the UI dependant on the response. For example, if the server is down, the UI tests should still run. Quick example, for login, mock if password failed then UI should show alert, however, if the login is successful the next page should be shown.Is there a way to mock requests when writing au