Added implementation in common lisp with unit-test

- added the existing implementation in common lisp with system-definition
- added a parachute-unit-test
- added a description for setup and running the unit-tests
- added a description for stubbing and mocking with cl-mock

common-lisp-parachute/tests/package.lisp

@@ -0,0 +1,12 @@
+;;;; package.lisp
+
+(defpackage :gilded-rose-tests
+  (:use :cl :gilded-rose)
+  (:import-from :parachute
+   :define-test
+   :is)
+  (:import-from :cl-mock
+   :with-mocks
+   :answer
+   :call-previous
+   :invocations))

common-lisp-parachute/tests/tests.lisp

@@ -0,0 +1,12 @@
+(in-package :gilded-rose-tests)
+
+(define-test gilded-rose-testsuite)
+
+(define-test "An item in gilded-rose is updated."
+  :parent gilded-rose-testsuite
+  (let* ((an-item (make-instance 'item :name "An item" :sell-in 1 :quality 1))
+	 (some-items (list an-item))
+	 (my-app (make-instance 'gilded-rose :items some-items)))
+    (update-quality my-app)
+    (is equal (slot-value (first (slot-value my-app 'items)) 'name) "Fix me")))
+