Midje intermingled tests

usage.clj

(ns my.namespace
  (:require [util :refer [dev-prelude]]))
; in dev, import midje
; in live, strip out any code that uses midje
(dev-prelude)

(def always (constantly true))
; tests! 
(facts "always"
    (always) => true))

util.clj

(defmacro safely [& stmts]
  `(try ~@stmts
        (catch Exception ~'e)))

(defn- are-we-in-dev? []
  (let [lein-home (System/getenv "LEIN_HOME")
        lein-no-dev (System/getenv "LEIN_NO_DEV")]
    (and lein-home
         (nil? lein-no-dev))))

(defmacro in-dev [& exprs]
  (when (are-we-in-dev?)
    `(do ~@exprs)))

(defmacro in-live [& exprs]
  (when-not (are-we-in-dev?)
    `(do ~@exprs)))

(defn ^:Private nil-macro [name]
  `(defmacro ~name [& ~'exprs] nil))

(defmacro ^:Private nil-macros [& names]
  `(do ~@(map nil-macro names)))

(defmacro dev-prelude []
  `(do
     (safely
      (in-dev (use 'midje.sweet))
      (in-live ~@(nil-macros facts fact unfinished tabular background)))))