Clojure: How To use-fixtures in Testing

Question

I am writing some unit tests that interact with a database. For this reason it is useful to have a setup and a teardown method in my unit test to create and then drop the table. However there are no docs :O on the use-fixtures method.

Here is what i need to do:

 (setup-tests)
 (run-tests)
 (teardown-tests)

I am not interested currently in running a setup and teardown before and after each test, but once before a group of tests and once after. How do you do this?

Answer 1

You can't use use-fixtures to provide setup and teardown code for freely defined groups of tests, but you can use :once to provide setup and teardown code for each namespace:

;; my/test/config.clj
(ns my.test.config)

(defn wrap-setup
  [f]
  (println "wrapping setup")
  ;; note that you generally want to run teardown-tests in a try ...
  ;; finally construct, but this is just an example
  (setup-test)
  (f)
  (teardown-test))    


;; my/package_test.clj
(ns my.package-test
  (:use clojure.test
        my.test.config))

(use-fixtures :once wrap-setup) ; wrap-setup around the whole namespace of tests. 
                                ; use :each to wrap around each individual test 
                                ; in this package.

(testing ... )

This approach forces some coupling between setup and teardown code and the packages the tests are in, but generally that's not a huge problem. You can always do your own manual wrapping in testing sections, see for example the bottom half of this blog post.