https://github.com/andrew/split

关于 AB 测试的一个 gem，一个 controller 代码如下：

def show
  @ab_style = ab_test("show_click", "origin", "testA")
end

def split_finish
  finished("show_click", :reset => false)
  render :nothing => true
end

官方描述 finished 方法中的 reset Reset after completion When a user completes a test their session is reset so that they may start the test again in the future.

To stop this behaviour you can pass the following option to the finished method:

finished('experiment_name', :reset => false) The user will then always see the alternative they started with.

但是每当我请求 split_finish 以后，再次请求 show，又会获得新的值。

split 里面的 ab_test 方法会 set 一个 user session，show action 以后：

{"session":{"session_id":"....","_csrf_token":"....","split":{"show_click:6":"origin"},}}

finished 以后：

{"session":{"session_id":"....","_csrf_token":".....","split":{},}}