racket/collects/tests/mzscheme/promise.ss
2009-01-16 05:46:07 +00:00

95 lines
3.7 KiB
Scheme

(load-relative "loadtest.ss")
(Section 'promise)
(require scheme/promise)
;; check that things are `promise?'s or not
(for ([v (list 1 '(1) (lambda () 1))])
(test #f promise? v))
(for ([v (list (delay 1) (lazy 1) (delay (delay 1)) (lazy (lazy 1)))])
(test #t promise? v))
(let ()
(define thunk1 (lambda () 1))
;; test a few different values
(define-syntax (t stx)
(define _ (datum->syntax stx '_ stx))
(syntax-case stx ()
[(t (f x ...))
(with-syntax ([_ _])
#'(begin (let ([_ 1]) (test _ f x ...))
(let ([_ '()]) (test _ f x ...))
(let ([_ '(1)]) (test _ f x ...))
(let ([_ thunk1]) (test _ f x ...))))]))
;; `force' is identity for non-promises
(t (force _))
;; basic checks that `delay' works as expected with all kinds of values
(t (force (delay _)))
(t (force (force (delay (delay _)))))
(t (force (delay (force (delay _)))))
;; basic checks that `lazy' works as expected with all kinds of values
(t (force (lazy _)))
(t (force (lazy (lazy _))))
(t (force (force (lazy (lazy _)))))
(t (force (lazy (lazy (lazy (lazy _))))))
;; check that `lazy' combines as expected with `delay' in regards to `force'
;; (generally, each `L*D?' sequence requires a force)
(t (force (lazy (delay _))))
(t (force (lazy (lazy (delay _)))))
(t (force (lazy (lazy (lazy (delay _))))))
;; two delays = two forces
(t (force (force (lazy (delay (delay _))))))
(t (force (force (delay (lazy (delay _))))))
(t (force (force (lazy (lazy (delay (delay _)))))))
(t (force (force (lazy (delay (lazy (delay _)))))))
(t (force (force (delay (lazy (lazy (delay _)))))))
(t (force (force (lazy (lazy (lazy (delay (delay _))))))))
(t (force (force (lazy (lazy (delay (lazy (delay _))))))))
(t (force (force (lazy (delay (lazy (lazy (delay _))))))))
(t (force (force (delay (lazy (lazy (lazy (delay _))))))))
;; now push the second force inside
(t (force (lazy (force (delay (delay _))))))
(t (force (delay (force (lazy (delay _))))))
(t (force (lazy (force (lazy (delay (delay _)))))))
(t (force (lazy (force (delay (lazy (delay _)))))))
(t (force (delay (force (lazy (lazy (delay _)))))))
(t (force (lazy (force (lazy (lazy (delay (delay _))))))))
(t (force (lazy (force (lazy (delay (lazy (delay _))))))))
(t (force (lazy (force (delay (lazy (lazy (delay _))))))))
(t (force (delay (force (lazy (lazy (lazy (delay _))))))))
(t (force (lazy (delay (force (delay _))))))
(t (force (lazy (lazy (force (delay (delay _)))))))
(t (force (lazy (delay (force (lazy (delay _)))))))
(t (force (lazy (lazy (force (lazy (delay (delay _))))))))
(t (force (lazy (lazy (force (delay (lazy (delay _))))))))
(t (force (lazy (delay (force (lazy (lazy (delay _))))))))
(t (force (lazy (lazy (delay (force (delay _)))))))
(t (force (lazy (lazy (lazy (force (delay (delay _))))))))
(t (force (lazy (lazy (delay (force (lazy (delay _)))))))))
;; more tests
(let ()
(define (force+catch p)
(with-handlers ([void (lambda (x) (cons 'catch x))]) (force p)))
(define (forced+running? p) (list (promise-forced? p) (promise-running? p)))
;; results are cached
(let ([p (delay (random 10000))])
(test #t equal? (force p) (force p)))
;; errors are cached
(let ([p (delay (error 'foo "blah"))])
(test #t equal? (force+catch p) (force+catch p)))
;; other raised values are cached
(let ([p (delay (raise (random 10000)))])
(test #t equal? (force+catch p) (force+catch p)))
;; test the predicates
(letrec ([p (delay (forced+running? p))])
(test '(#f #f) forced+running? p)
(test '(#f #t) force p)
(test '(#t #f) forced+running? p))
)
(report-errs)