Midje的‘`with state-changes`’和函数调用

Question

下面的代码可以工作(很明显)：

(use [midje.sweet])

(with-state-changes [(before :contents (println "setup") :after (println "teardown"))]
  (fact "one" 
    (println "doing 1")
    1 => 1)
  (fact "two"
    (println "doing 2")
    (+ 1 1) => 2))

输出是预期的：

setup
doing 1
doing 2
teardown

但我希望将我的事实分组到一个单独的函数中，如下所示：

(defn my-facts []
  (fact "one" ...)
  (fact "two" ...)
  #_( ... ))

(with-state-changes [(before :contents (println "setup") :after (println "teardown"))]
  (my-facts))

这一次，midje不能执行代码，我得到以下错误：

Midje could not understand something you wrote: 
        Background prerequisites created by the wrapping version of
        `against-background` only affect nested facts. This one
        wraps no facts.

        Note: if you want to supply a background to all checks in a fact, 
        use the non-wrapping form. That is, instead of this:
            (fact 
              (against-background [(f 1) => 1] 
                (g 3 2 1) => 8 
                (h 1 2) => 7)) 
        ... use this:
            (fact 
              (g 3 2 1) => 8 
              (h 1 2) => 7 
              (against-background (f 1) => 1)) 

有什么方法可以实现我的目标吗？我想使用midje的设置和拆卸功能，但仍然可以将我的事实包含在一个单独的fn中。

Answer 1

我花了一些时间查看了Midje的源代码，我认为这是不可能的。在宏扩展期间，Midje严重依赖于解析和重写代码，当它获得您的单独函数调用的结果时，Midje宏(事实等)已经被扩展和评估。如果你真的下定决心，你可能会做到这一点，但它将不得不使用宏的单独事实，而不是一个函数，以便让Midje访问您的原始事实表单。Midje在很大程度上都是宏，所以很难使用其他任何东西来与之交互。