;;; Common Lisp testing framework

;;; Copyright 2015 Dave Astels
;;; MIT License


(defvar number-of-tests 0)
(defvar number-of-failures 0)

(defvar failure-messages '())

(defvar verbose-tests nil)
(defvar context-name "")


(defun reset-testing ()
  (setf number-of-tests 0)
  (setf number-of-failures 0)
  (setf number-of-errors 0)
  (setf failure-messages '())
  (setf error-messages '())
  (setf verbose-tests nil))


(defmacro context (label &rest body)
  (if (not (or (symbolp label) (stringp label)))
      (error "The label of a describe must be a symbol or string.")
      `(progn (when verbose-tests
                (format t "Context: ~A~%" ,label))
              (setf context-name ,label)
              ,@body)))


(defun log-pass (msg)
  (setf number-of-tests (1+ number-of-tests))
  (when verbose-tests
    (format t "  ~A - ok~%" msg)))


(defun log-failure (prefix msg)
  (setf number-of-failures (1+ number-of-failures))
  (let ((failure-message (format nil "~A: ~A - ~A" context-name prefix msg)))
    (setf failure-messages (cons failure-message failure-messages))
    (when verbose-tests
      (format t "  ~A - failed: ~A~%" prefix msg))))


(defmacro assert-true (sexpr)
  `(let ((actual (eval ,sexpr))
         (msg (format nil "(assert-true ~A)" ',sexpr)))
     (if actual
         (log-pass msg)
         (log-failure msg "expected true, but was false"))))


(defmacro assert-false (sexpr)
  `(let ((actual (eval ,sexpr))
         (msg (format nil "(assert-false ~A)" ',sexpr)))
     (if (not actual)
         (log-pass msg)
         (log-failure msg "expected false, but was true"))))


(defmacro assert-null (sexpr)
  `(let ((actual (eval ,sexpr))
         (msg (format nil "(assert-null ~A)" ',sexpr)))
     (if (null actual)
         (log-pass msg)
         (log-failure msg "expected null, but wasn't"))))


(defmacro assert-not-null (sexpr)
  `(let ((actual (eval ,sexpr))
         (msg (format nil "(assert-not-null ~A)" ',sexpr)))
     (if (not (null actual))
         (log-pass msg)
         (log-failure msg "expected not null, but was"))))


(defmacro assert-eq (sexpr expected-sexpr)
  `(let* ((actual ,sexpr)
          (expected ,expected-sexpr)
          (msg (format nil "(assert-eq ~A ~A)" ',sexpr ',expected-sexpr)))
     (if (eq actual expected)
         (log-pass msg)
         (log-failure msg (format nil "expected ~A, but was ~A" expected actual)))))


(defmacro assert-neq (sexpr expected-sexpr)
  `(let* ((actual ,sexpr)
          (expected ,expected-sexpr)
          (msg (format nil "(assert-neq ~A ~A)" ',sexpr ',expected-sexpr)))
     (if (not (eq actual expected))
         (log-pass msg)
         (log-failure msg (format nil "did not expect ~A, but it was" expected)))))


(defun run-tests (test-dir &optional (verbose nil))
  (setf failure-messages '())
  (setf verbose-tests verbose)
  (mapcar #'load (cl-fad:list-directory test-dir))
  (format t "~%Failures:~%")
  (mapcar (lambda (m) (format t "  ~A~%" m))
          failure-messages))