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Why write programs in Common Lisp but tests like Java? Meet CheckL!

CheckL

Why write programs in Common Lisp but tests like Java?

My workflow for writing Common Lisp tends to be like this:

  • Write a bit of lisp, perhaps a function, class, or structure
  • Write a snippet in a scratch buffer to test
  • Fix if necessary and repeat

Testing is already inherent in this process, all we need is a little bit of Common Lisp magic to take advantage of it. Thus, CheckL:

(defun foo ()
  (+ 1 1))

(check () (foo)) ;; => 2

(defun foo ()
  (+ 1 2))

(check () (foo))

    |
    v

Result 0 has changed: 3
Previous result: 2
   [Condition of type CHECKL::RESULT-ERROR]

Restarts:
 0: [USE-NEW-VALUE] The new value is correct, use it from now on.
 1: [SKIP-TEST] Skip this, leaving the old value, but continue testing
 2: [RETRY] Retry SLIME interactive evaluation request.
 3: [*ABORT] Return to SLIME's top level.
 4: [TERMINATE-THREAD] Terminate this thread (#<THREAD "worker" RUNNING {100586AB13}>)

See the full documentation for more details!