racket/collects/tests/racket/for-util.rkt
2011-07-27 05:47:46 +01:00

110 lines
5.4 KiB
Racket

#lang racket/base
(require (for-syntax racket/base))
(provide test-multi-sequence
test-sequence)
;; Utilities used by various tests of sequences
(define-syntax (test-multi-sequence stx)
(syntax-case stx ()
[(_ [(v ...) ...] gen)
(with-syntax ([(id ...) (generate-temporaries #'((v ...) ...))]
[(id2 ...) (generate-temporaries #'((v ...) ...))]
[((v2 ...) ...)
(apply map list (map syntax->list (syntax->list #'((v ...) ...))))])
#'(begin
(test `((v2 ...) ...) 'gen (for/list ([(id ...) gen])
(list id ...)))
(test-values `((v ...) ...) (lambda ()
(for/lists (id2 ...) ([(id ...) gen])
(values id ...))))
(test #t 'gen (for/and ([(id ...) gen])
(and (member (list id ...) `((v2 ...) ...)) #t)))
(test (list (for/last ([(id ...) gen])
(list id ...)))
'gen (for/and ([(id ...) gen])
(member (list id ...) `((v2 ...) ...))))
(test (for/first ([(id ...) gen])
(list id ...))
'gen (for/or ([(id ...) gen])
(car (member (list id ...) `((v2 ...) ...)))))
(void)))]))
(define-syntax test-sequence
(syntax-rules ()
[(_ [seq] gen) ; we assume that seq has at least 2 elements, and all are unique
(begin
;; Some tests specific to single-values:
(test `seq 'gen (for/list ([i gen]) i))
(test `seq 'gen (for/list ([i gen][b gen]) i))
(test `seq 'gen (for/list ([i gen][b gen]) b))
(test `seq 'gen (for*/list ([i gen][b '(#t)]) i))
(test (map (lambda (x) #t) `seq) 'gen (for*/list ([i gen][b '(#t)]) b))
(test (append `seq `seq) 'gen (for*/list ([b '(#f #t)][i gen]) i))
(test (append `seq `seq) 'gen (for/list ([b '(#f #t)] #:when #t [i gen]) i))
(test (append `seq `seq) 'gen (for/list ([b '(#t #t #f)] #:when b [i gen]) i))
(test (append `seq `seq) 'gen (for/list ([b '(#f #t)] #:unless #f [i gen]) i))
(test (append `seq `seq) 'gen (for/list ([b '(#f #f #t)] #:unless b [i gen]) i))
(test `seq 'gen (let ([g gen]) (for/list ([i g]) i)))
(test `seq 'gen (let ([r null])
(for ([i gen]) (set! r (cons i r)))
(reverse r)))
(test `seq 'gen (reverse (for/fold ([a null]) ([i gen])
(cons i a))))
(test `seq 'gen (let-values ([(more? next) (sequence-generate gen)])
(let loop ()
(if (more?)
(cons (next) (loop))
null))))
(test-values `(seq seq) (lambda ()
(for/lists (r1 r2) ([id gen])
(values id id))))
(test (list (for/last ([i gen]) i)) 'gen (for/and ([i gen]) (member i `seq)))
(test `seq 'gen (for/or ([i gen]) (member i `seq)))
(test (for/first ([i gen]) i) 'gen (for/or ([i gen]) (and (member i `seq) i)))
(test (for/sum ([i gen]) (if (number? i) i 0)) 'gen
(for/fold ([n 0]) ([i gen]) (if (number? i) (+ i n) n)))
(test (for/product ([i gen]) (if (number? i) i 1)) 'gen
(for/fold ([n 1]) ([i gen]) (if (number? i) (* i n) n)))
(test #t 'gen (for/and ([(i k) (in-parallel gen `seq)])
(equal? i k)))
(test #f 'gen (for/and ([i gen])
(member i (cdr (reverse `seq)))))
(test #f 'gen (for/or ([i gen]) (equal? i 'something-else)))
(let ([count 0])
(test #t 'or (for/or ([i gen]) (set! count (add1 count)) #t))
(test 1 'count count)
(test #f 'or (for/or ([i gen]) (set! count (add1 count)) #f))
(test (+ 1 (length `seq)) 'count count)
(set! count 0)
(let ([second (for/last ([(i pos) (in-parallel gen (in-naturals))] #:when (< pos 2))
(set! count (add1 count))
i)])
(test second list-ref `seq 1)
(test 2 values count)
(for ([i gen] #:when (equal? i second)) (set! count (add1 count)))
(for* ([i gen] #:when (equal? i second)) (set! count (add1 count)))
(test 4 values count)
(for ([i (stop-before gen (lambda (x) (equal? x second)))]) (set! count (add1 count)))
(test 5 values count)
(let ([g (stop-before gen (lambda (x) (equal? x second)))])
(for ([i g]) (set! count (add1 count))))
(test 6 values count)
(for ([i (stop-after gen (lambda (x) (equal? x second)))]) (set! count (add1 count)))
(test 8 values count)
(let ([g (stop-after gen (lambda (x) (equal? x second)))])
(for ([i g]) (set! count (add1 count))))
(test 10 values count))
(set! count 0)
(test #t 'and (for/and ([(e idx) (in-indexed gen)]) (set! count (add1 count)) (equal? idx (sub1 count))))
(test #t 'and (let ([g (in-indexed gen)])
(set! count 0)
(for/and ([(e idx) g]) (set! count (add1 count)) (equal? idx (sub1 count)))))
(void))
;; Run multi-value tests:
(test-multi-sequence [seq] gen))]
[(_ seqs gen)
(test-multi-sequence seqs gen)]))