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test-simple.el is :

  • Simple -- no need for context macros, enclosing specifications, or required test tags. But if you want, you still can add custom assert failure messages or add notes before a group of tests.
  • Accomodates both interactive and non-interactive use:
    • For interactive use one can use eval-last-sexp, eval-region, and eval-buffer
    • For non-interactive use run as: emacs --batch --no-site-file --no-splash --load <test-lisp-code.el>

I use this in my Debugger front end.

Here is an example found in the examples directory.

In file gcd.el:

(defun gcd(a b)
  "Greatest Common Divisor of A and B"
  ;; Make a < b
  (if (> a b)
      (let ((c a))
	(setq a b)
	(setq b c)))
   ((< a 0) nil)
   ((or (= 0 (- b a)) (= a 1)) a)
   (t (gcd (- b a) a))

In file test-gcd.el in the same directory:

(require 'test-simple)
(test-simple-start) ;; Zero counters and start the stop watch.

;; Use (load-file) below because we want to always to read the source.
;; Also, we don't want no stinking compiled source.
(assert-t (load-file "./gcd.el")
	  "Can't load gcd.el - are you in the right directory?" )

(note "degenerate cases")

(assert-nil (gcd 5 -1) "using positive numbers")
(assert-nil (gcd -4 1) "using positive numbers, switched order")
(assert-raises error (gcd "a" 32)
	       "Passing a string value should raise an error")

(note "GCD computations")
(assert-equal 1 (gcd 3 5) "gcd(3,5)")
(assert-equal 8 (gcd 8 32) "gcd(8,32)")

(end-tests) ;; Stop the clock and print a summary

Edit (with Emacs of course) test-gcd.el and run M-x eval-current-buffer

You should see in buffer *test-simple*:

0 failures in 6 assertions (0.002646 seconds)

Now let's try from a command line:

$ emacs --batch --no-site-file --no-splash --load test-gcd.el
Loading /src/external-vcs/emacs-test-simple/example/gcd.el (source)...
0 failures in 6 assertions (0.000723 seconds)

You can run noninteractive tests inside Emacs by test-simple-run. Add the following at a test file:

;;;; (test-simple-run "emacs -batch -L %s -l %s" (file-name-directory (locate-library "test-simple.elc")) buffer-file-name)

Press C-x C-e at the test-simple-run line to run this test file. Then press C-x C-z, which is customizable by test-simple-runner-key, to run it more. If you have installed bpr package, use it by default because it only pops up window when the running program exits abnormally.

test-simple-run can be called interactively. In this case, the command line is set above as the simplest case. But you run test with dependency, you must use the sexp comment form.

;;;; (test-simple-run "emacs -batch -L %s -L %s -l %s" (file-name-directory (locate-library "test-simple.elc")) (file-name-directory (locate-library "foo")) buffer-file-name)

Author: Rocky Bernstein