Jake-The-Human/FP3

final project exploration #2: use a Racket library that will be part of your final project

RackUnit

My name: Jake Adamson

When I was think about what I could make using racket unit test that was interesting. I realized that you could use closure to keep the the data shielded from any outside side affects. In this example I use a let to make the list to only live where the tests are being done. Another interesting thing is that you can embedded checks in to functions I use this to look inside list to see if the list consists of positive even numbers.

;; this will short circut if one test fails the test will end
(test-case
 "Test Example w/ closure"
 (let ([foo (filter even? (range 1 100))])
   (for-each ;; checks that each element of a list is only pos even and greater then zero
    (lambda (elt)
      (and (check-pred even? elt) (check-pred positive? elt)))
    foo)
   (check = (length foo) 49)
   (check-equal? (car foo) 2) ; foo '(2 4 6 8 ... 94 96 98)
   (check = (last foo) 98)))

Also another interesting feature of racket unit test is that they short circuit. As you can see from the output that it does not evaluate any cases passed (check = 0 10);

(test-case
 "Short circuit"
 (check = 3 3)
 (check = 0 10)
 (check = 4 4) ;; does not check
 (check = 200 45));; does not check this when test run this wont fail b/c it short circiut

Output:

How this lib will help with our project is that it will be used to check that the object and all its helper helper function are working properly. Here a test that will test our project I wrote it before I started writing the objects function all I have done is come up with the functions I think it will use. I wrote the test first because I read that you are supposed to do that in order not to try and make your test work. Kinda like control groups for testing medicine I guess.

(test-begin
 "Test string gagggagaggcgagaaa"
 (let ([mm (markModel "test.txt" 1)])
   (check = (order mm) 1)
   (check-not-equal? (order mm) 5)
   (check-equal? (kgram mm) "gagggagaggcgagaaa")
   (check-not-equal? (kgram mm) "jakejakejakejake")
   (check = (freqOfStr mm "j") 0) ;; number of j should be 0
   (check = (freqOfStr mm "g") 9) ;; there are 9 g
   (check = (freqOfStr mm "a") 7)
   (check = (freqOfStr mm "c") 1)
   (check =  (freqOfChar mm "g" "a") 5)
   (check =  (freqOfChar mm "g" "c") 1)
   (check =  (freqOfChar mm "c" "g") 1)
   (check =  (freqOfChar mm "g" "g") 3)
   (check =  (freqOfChar mm "a" "a") 2)))