(import r7rs
        (prefix (hascheme base) ha:)
        (hascheme eager)
        (srfi 64))

(cond-expand
  (chicken-5 (test-runner-current (test-runner-create)))
  (else))

(ha:define
 (hascheme-natural-numbers)
 (ha:let loop ((i 0)) (ha:seq i (ha:cons i (loop (ha:+ i 1))))))

(ha:define (square-of-list list) (ha:map ha:square list))

(test-group "lists"
  (test-assert
   "cons is lazy, car"
   (force (ha:car (ha:cons #t (ha:error "boom")))))
  (test-assert
   "cons is lazy, cdr"
   (guard (x ((equal? (force (error-object-message x)) "boom") #t)
             (else #f))
     (force (ha:cdr (ha:cons #f (ha:error "boom"))))
     #f))
  (test-equal
   1000
   (force (ha:list-ref (hascheme-natural-numbers) 1000)))
  (let ((flag '()))
    (test-equal
     "map is lazy"
     '(1000)
     (begin
       (force (ha:list-ref (ha:map (ha:lambda (x) (set! flag
                                                        (cons (force x) flag)))
                                   (hascheme-natural-numbers))
                           1000))
       flag)))
  (test-equal "runs in bounded space"
              (square 1000)
              (force (ha:list-ref (square-of-list (hascheme-natural-numbers))
                                  1000))))