(ns test-ns
 (:require [clojure.spec :as s]
           [clojure.spec.test :as stest]]))

(defn test-func [a]
  (str a))

(s/def ::int-ret integer?)

(s/fdef test-func
        :args (s/cat :a string?)
        :ret ::int-ret)

(stest/instrument `test-func)

(test-func "test")