racket/collects/web-server/tests/lang/labels-test.ss
Jay McCarthy 4a39355dfc Organzing tests
svn: r6449
2007-06-01 17:49:14 +00:00

110 lines
3.7 KiB
Scheme

(module labels-test mzscheme
(require (planet "test.ss" ("schematics" "schemeunit.plt" 2))
(planet "util.ss" ("schematics" "schemeunit.plt" 2))
(lib "etc.ss")
(lib "file.ss")
(lib "labels.ss" "web-server" "lang"))
(provide labels-tests)
(require/expose (lib "labels.ss" "web-server" "lang") (add1/string))
(define THE-TEST-FILENAME (make-temporary-file))
(define l1 (make-labeling #"foo" THE-TEST-FILENAME))
(define l2 (make-labeling #"foo" THE-TEST-FILENAME))
(define l3 (make-labeling #"bar" THE-TEST-FILENAME))
(define l4 (make-labeling #"baz" THE-TEST-FILENAME))
(define race-test-file (make-temporary-file))
(define (genbytes)
(string->bytes/utf-8
(symbol->string (gensym))))
(define-struct cell (sema ival new-val))
(define (create-cell ival)
(make-cell (make-semaphore) ival #f))
;; race?: (listof alpha) (alpha -> beta) ((listof beta) -> boolean)) -> boolean
;; compute a list of values in parallel and determine if the result indicates a
;; race condition.
(define (race? initial-vals make-new-val check-new-vals)
(let ([cells (map create-cell initial-vals)])
(for-each
(lambda (cell)
(thread
(lambda ()
(dynamic-wind
void
(lambda () (set-cell-new-val! cell (make-new-val (cell-ival cell))))
(lambda () (semaphore-post (cell-sema cell)))))))
cells)
(for-each
(lambda (cell)
(semaphore-wait (cell-sema cell)))
cells)
(with-handlers ([void
(lambda (the-exn) #t)])
(check-new-vals (map cell-new-val cells)))))
(define (make-labeling-race? n)
(delete-tag-list! race-test-file)
(race? (build-list n (lambda (i) (genbytes)))
(lambda (some-bytes)
(make-labeling some-bytes race-test-file))
(lambda (labelings)
(let loop ([label 0]
[labelings labelings])
(if (null? labelings)
#f
(let ([new-label ((car labelings))])
(or (eqv? new-label label)
(loop new-label (cdr labelings)))))))))
(define (delete-tag-list!-race? n)
(race? (build-list n (lambda (i) #"foo"))
(lambda (some-bytes)
(delete-tag-list! race-test-file)
(make-labeling some-bytes race-test-file))
(lambda (labelings)
(let* ([syms (map (lambda (l) (l)) labelings)]
[sym0 (car syms)])
(not
(andmap
(lambda (sym)
(eqv? sym0 sym))
syms))))))
(define labels-tests
(test-suite
"Module Labeling"
(test-case
"Test the tag incrementing scheme"
(check string=? "b" (add1/string ""))
(check string=? "A" (add1/string "z"))
(check string=? "B" (add1/string "A"))
(check string=? "b" (add1/string "a"))
(check string=? "ab" (add1/string "Z"))
(check string=? "aab" (add1/string "ZZ"))
(check string=? "Azz" (add1/string "zzz"))
(check string=? "aaaab" (add1/string "ZZZZ"))
(check string=? "baaab" (add1/string "aaaab")))
(test-case
"The same program produces the same labeling"
(check-eqv? (l1) (l2))
(check-eqv? (l1) (l2)))
(test-case
"Different programs produce different labelings"
(check-false (eqv? (l3) (l4))))
(test-case
"Check for race condition on make-labeling"
(check-false (make-labeling-race? 256)))
(test-case
"Check for race condition on delete-tag-list!"
(check-false (delete-tag-list!-race? 256))))))