In Clojure the unit under test is the function. Unit test coverage should test all public function that form the API of their respective namespace.
clojure.test namespace provides a unit testing framework and is included in the Clojure library, so is available in all Clojure projects.
Principles for writing test codeλ︎
testnamespace for each
deftestfunction for each function under test
isassertions for one function
- Group assertions in
testingand provide a meaningful description of that grouping, adding more information when reviewing test failures especially for larger code bases.
A test namespace has a singular purpose to test a matching application namespace. Therefore the idiomatic approach is to
:refer specific functions from
The namespace under test should be referred, using a meaningful alias name.
clojure.test to the namespace definition along with the namespace under test.
(ns practicalli.app-namespace-test (:require '[clojure.test :refer [deftest is testing]] [practicalli.app-namespace :as app-namespace]))
Providing an alias that is the same name as the namespace being tested creates easily readable test code.
Project structure with testsλ︎
By convention, separate
test directories are used to hold the source code and the code that tests the source code.
For each source code file in
src there should be a corresponding file in test with the same name and
For example, code to test the
src/codewars/rock_paper_scissors.clj is saved in the file
Create Projects from templates
Templates typically include a parallel
src directory structure. The
clj-new tool has build it templates (app, lib) and will create
test directories in the projects it creates.
clojure -X:project/new :template app :name practicalli/rock-paper-scissors-lizard-spock
- Example based unit testing in Clojure - PurelyFunctional.tv