CLUnit is a Common Lisp unit testing framework. It is designed to be easy to use so that you can quickly start testing.

  • Author: Tapiwa Gutu
  • Maintainer of this fork: cage

CLUnit provides a rich set of features aimed at improving your unit testing experience:

  • Multiple inheritance for test suites allows you to group tests into hierarchies.
  • Composes the test results of each test run into a single report.
  • Allows redefinition of inline functions and macros without having to redefine your tests.
  • Supports composable test suite fixtures.
  • Allows for an interactive testing process which gives you access to the test environment.
  • Provides visual feedback of the unit test progress.
  • Extensible test reporting. Builtin support for default reporting and "Test Anything Protocol" (TAP) output.
  • Released under MIT license

Check out the comprehensive CLUnit Tutorial.


  (ql:quickload "clunit")
  (use-package :clunit)

  ;; Test suite for all number operation tests.
  (defsuite NumberSuite ())

  ;; Test suite for floating point operations
  (defsuite FloatSuite (NumberSuite))

  (defsuite IntegerSuite (NumberSuite))

  ;; Define a test called TEST-INT1
  (deftest test-int1 (IntegerSuite)
    (assert-true  (= 1 1))
    (assert-equalp 4 (+ 2 2)))

  ;; Define a test called TEST-FLOAT1
  (deftest test-float1 (FloatSuite)
    (assert-true (= 1.0 -1.0))
    (assert-equalp 4.0 (+ 2.0 2.0)))

  (print (run-suite 'NumberSuite))

which produces the output:


    NUMBERSUITE: (Test Suite)

        INTEGERSUITE: (Test Suite)
            TEST-INT1: ..

        FLOATSUITE: (Test Suite)
            TEST-FLOAT1: F.


        TEST-FLOAT1: Expression: (= 1.0 -1.0)
                     Expected: T
                     Returned: NIL

    Test functions:
        Executed: 2
        Skipped:  0

    Tested 4 assertions.
        Passed: 3/4 ( 75.0%)
        Failed: 1/4 ( 25.0%)

(if you are entering forms in the REPL, the ``print`` form is not usually needed).

Each test, like ``test-int1`` in the above example, can contain a number of assertions, given in the table below:

Assertion Description
``assert-true EXPRESSION`` Passes if the expression ``EXPRESSION`` is not ``NIL``
``assert-false EXPRESSION`` Passes if ``EXPRESSION`` is ``NIL``
``assert-eq VALUE EXPRESSION`` Passes if ``(EQ VALUE EXPRESSION)`` returns true
``assert-eql VALUE EXPRESSION`` Passes if ``(EQL VALUE EXPRESSION)`` returns true
``assert-equal VALUE EXPRESSION`` Passes if ``(EQUAL VALUE EXPRESSION)`` returns true
``assert-equalp VALUE EXPRESSION`` Passes if ``(EQUALP VALUE EXPRESSION)`` returns true
``assert-equality TEST VALUE EXPRESSION`` Passes if ``(FUNCALL TEST VALUE EXPRESSION)`` returns true
``assert-equality* VALUE EXPRESSION`` Passes if ``(FUNCALL clunit-equality-test VALUE EXPRESSION)`` returns true. By default clunit-equality-test is ``EQUALP``
``assert-expands EXPANSION EXPRESSION`` Tests macro expansion, passes if ``(EQUALP EXPANSION (MACROEXPAND-1 EXPRESSION))`` is true
``assert-condition CONDITION EXPRESSION`` Passes if ``EXPRESSION`` signals ``CONDITION``
``assert-fails FORMAT-STRING`` Force test to fail, giving a format string for the message

All of these tests take optional forms, which are evaluated and printed if the test fails. These can be used to provide test diagnostics or documentation. For example

  (deftest test-suiteless ()
    (let ((a 1) (b 2) (c 3))
      (assert-true (= a b c) "This assertion is meant to fail." a b c )))

  (run-test 'test-suiteless :report-progress nil)

produces the output:

    TEST-SUITELESS: Expression: (= A B C)
                    Expected: T
                    Returned: NIL
                    This assertion is meant to fail.
                    A => 1
                    B => 2
                    C => 3

    Test functions:
        Executed: 1
        Skipped:  0

    Tested 1 assertion.
        Passed: 0/1 (  0.0%)
        Failed: 1/1 (100.0%)
        Errors: 0/1 (  0.0%)

(if not in a REPL, you may have to print the return value of ``run-test``).


Please file bug report on the issue tracker


This is a fork of .

Tapiwa Gutu <>, cage