racket/collects/deinprogramm/signature/signature-unit.rkt
Mike Sperber 69963a1f2c Fix bug in struct-wrap signature checking.
Only check the fields if we know the struct type is right.
2011-01-06 13:53:51 +01:00

730 lines
23 KiB
Racket

#lang scheme/base
(provide signature-messages^ signatures^ signatures@)
(require racket/unit)
(require scheme/promise
mzlib/struct
(only-in racket/list first rest)
(for-syntax scheme/base)
(for-syntax stepper/private/shared))
(require deinprogramm/signature/signature)
(require deinprogramm/quickcheck/quickcheck)
(define-signature signature-messages^
(recursive-signature-message
parameter-count-mismatch-message
argument-count-mismatch-message))
(define-signature signatures^
(make-delayed-signature
make-call-signature
make-property-signature
make-predicate-signature
make-type-variable-signature
make-list-signature
make-vector-signature
make-mixed-signature
make-combined-signature
make-case-signature
make-procedure-signature
procedure-signature-info?
procedure-signature-info-arg-signatures procedure-signature-info-return-signature
make-lazy-wrap-info lazy-wrap-info-constructor lazy-wrap-info-raw-accessors
prop:lazy-wrap lazy-wrap? lazy-wrap-ref
make-lazy-wrap-signature
check-lazy-wraps!
make-pair-signature checked-car checked-cdr checked-first checked-rest))
(define-unit signatures@
(import signature-messages^)
(export signatures^)
(define (make-delayed-signature name promise)
(make-signature name
(lambda (self obj)
((signature-enforcer (force promise)) self obj))
(delay (signature-syntax (force promise)))
#:arbitrary-promise
(delay
(force (signature-arbitrary-promise (force promise))))
#:info-promise
(delay
(force (signature-info-promise (force promise))))
#:<=?-proc
(lambda (this-info other-info)
((signature-<=?-proc (force promise)) this-info other-info))
#:=?-proc
(lambda (this-info other-info)
((signature-=?-proc (force promise)) this-info other-info))))
; specialized version of the above, supports comparison
; the promise must produce the result of (proc . args), but its passed separately
; to give us the right location on backtrace
(define (make-call-signature name promise proc-promise args-promise syntax)
(make-signature name
(lambda (self obj)
((signature-enforcer (force promise)) self obj))
(delay syntax)
#:arbitrary-promise
(delay
(force (signature-arbitrary-promise (force promise))))
#:info-promise
(delay
(make-call-info promise (force proc-promise) (force args-promise)))
#:=?-proc
(lambda (this-info other-info)
(and (call-info? other-info)
(eqv? (force proc-promise) (call-info-proc other-info))
(equal? (force args-promise) (call-info-args other-info))))))
(define-struct call-info (promise proc args) #:transparent)
; klude to support mixed
(define (real-signature-info sig)
(let ((raw-info (force (signature-info-promise sig))))
(if (call-info? raw-info)
(real-signature-info (force (call-info-promise raw-info)))
(force raw-info))))
(define (make-property-signature name access signature syntax)
(let ((enforce (signature-enforcer signature)))
(make-signature name
(lambda (self obj)
(enforce self (access obj)) ; #### problematic: enforcement doesn't stick
obj)
syntax)))
(define (make-predicate-signature name predicate-promise syntax)
(make-signature
name
(lambda (self obj) ; dynamic binding because of syntax remapping via `signature-update-syntax'
(if ((force predicate-promise) obj)
obj
(begin
(signature-violation obj self #f #f)
obj)))
(delay syntax)
#:info-promise
(delay (make-predicate-info (force predicate-promise)))
#:=?-proc
(lambda (this-info other-info)
(and (predicate-info? other-info)
(eq? (force predicate-promise)
(predicate-info-predicate other-info))))))
(define-struct predicate-info (predicate) #:transparent)
(define (make-type-variable-signature name syntax)
(make-signature
name
(lambda (self obj) obj)
(delay syntax)
#:info-promise
(delay (make-type-variable-info))
#:=?-proc
(lambda (this-info other-info)
(type-variable-info? other-info))))
; maps lists to pairs of signature, enforced value
(define lists-table (make-weak-hasheq))
(define (make-list-signature name arg-signature syntax)
(make-signature
name
(lambda (self obj)
;;(write (list 'list obj) (current-error-port)) (newline (current-error-port))
(let recur ((l obj))
(define (go-on)
(let ((enforced (cons (apply-signature arg-signature (car l))
(recur (cdr l)))))
(hash-set! lists-table l (cons self enforced))
(hash-set! lists-table enforced (cons self enforced))
enforced))
(cond
((null? l)
l)
((not (pair? l))
(signature-violation obj self #f #f)
obj)
((hash-ref lists-table l #f)
=> (lambda (seen)
;;(write (list 'seen seen (eq? self (car seen))) (current-error-port)) (newline (current-error-port))
(if (eq? self (car seen))
(cdr seen)
(go-on))))
(else
(go-on)))))
syntax
#:arbitrary-promise
(delay
(lift->arbitrary arbitrary-list arg-signature))
#:info-promise
(delay (make-list-info arg-signature))
#:=?-proc
(lambda (this-info other-info)
(and (list-info? other-info)
(signature=? arg-signature (list-info-arg-signature other-info))))))
(define-struct list-info (arg-signature) #:transparent)
(define (lift->arbitrary proc . signatures)
(let ((arbitraries (map force (map signature-arbitrary-promise signatures))))
(if (andmap values arbitraries)
(apply proc arbitraries)
#f)))
(define vectors-table (make-weak-hasheq)) ; #### ought to do ephemerons, too
(define (make-vector-signature name arg-signature syntax)
(make-signature
name
(lambda (self obj)
(define (check old-sigs)
(let ((old-sigs (cons arg-signature old-sigs)))
(hash-set! vectors-table obj old-sigs)
(let* ((orig (vector->list obj))
(els (map (lambda (x)
(apply-signature arg-signature x))
orig)))
(if (andmap eq? orig els)
obj
(let ((new (list->vector els)))
(hash-set! vectors-table obj new old-sigs)
obj)))))
(cond
((not (vector? obj))
(signature-violation obj self #f #f)
obj)
((hash-ref vectors-table obj #f)
=> (lambda (old-sigs)
(if (ormap (lambda (old-sig)
(signature<=? old-sig arg-signature))
old-sigs)
obj
(check old-sigs))))
(else
(check '()))))
syntax
#:arbitrary-promise
(delay
(lift->arbitrary arbitrary-vector arg-signature))
#:info-promise
(delay (make-vector-info arg-signature))
#:=?-proc
(lambda (this-info other-info)
(and (vector-info? other-info)
(signature=? arg-signature (vector-info-arg-signature other-info))))))
(define-struct vector-info (arg-signature) #:transparent)
(define (make-mixed-signature name alternative-signatures syntax)
(letrec ((alternative-signatures-promise
(delay
(normalize-mixed-signatures mixed-signature alternative-signatures)))
(mixed-signature
(make-signature
name
(lambda (self obj)
(let loop ((alternative-signatures (force alternative-signatures-promise)))
(cond
((null? alternative-signatures)
(signature-violation obj self #f #f)
obj)
((eq? (car alternative-signatures) self)
(raise
(make-exn:fail:contract
(string->immutable-string
(if name
(format "~a: ~a" recursive-signature-message)
recursive-signature-message))
(current-continuation-marks))))
(else
(check-signature (car alternative-signatures)
obj
values
(lambda () (loop (cdr alternative-signatures))))))))
(delay syntax)
#:info-promise
(delay (make-mixed-info (force alternative-signatures-promise)))
#:arbitrary-promise
(delay
(let* ((arbitrary-promises (map signature-arbitrary-promise alternative-signatures))
(raising-promises
(map (lambda (prm)
(delay
(or (force prm)
(error "Signatur hat keinen Generator")))) ; #### src location
arbitrary-promises)))
(arbitrary-mixed
(map (lambda (sig arbp)
(cons (signature->predicate sig)
arbp))
alternative-signatures raising-promises))))
#:=?-proc
(lambda (this-info other-info)
(and (mixed-info? other-info)
(andmap signature=?
(mixed-info-signatures this-info)
(mixed-info-signatures other-info))))
#:<=?-proc
(lambda (this-info other-info)
(and (mixed-info? other-info)
(mixed-signature<=? (mixed-info-signatures this-info)
(mixed-info-signatures other-info)))))))
mixed-signature))
(define (mixed-signature<=? sigs1 sigs2)
(andmap (lambda (sig1)
(ormap (lambda (sig2)
(signature<=? sig1 sig2))
sigs2))
sigs1))
; Flatten out mixed signatures, and fold in in the lazy-wrap
; signatures
(define (normalize-mixed-signatures mixed-signature sigs)
(fold-lazy-wrap-signatures mixed-signature (flatten-mixed-signatures sigs)))
(define (flatten-mixed-signatures sigs)
(apply append
(map (lambda (sig)
(let ((info (force (signature-info-promise sig))))
(if (mixed-info? info)
(mixed-info-signatures info)
(list sig))))
sigs)))
(define-struct mixed-info (signatures) #:transparent)
(define (check-signature sig val success fail)
((let/ec exit
(let ((enforced
(call-with-signature-violation-proc
(lambda (signature syntax msg blame)
(exit fail))
(lambda ()
(apply-signature sig val)))))
(lambda () (success enforced))))))
(define (signature->predicate sig)
(lambda (val)
(check-signature sig val (lambda (_) #t) (lambda () #f))))
(define (make-combined-signature name signatures syntax)
(make-signature
name
(lambda (self obj)
(let ((old-violation-proc (signature-violation-proc)))
((let/ec exit
(call-with-signature-violation-proc
(lambda (signature syntax msg blame)
(exit
(lambda ()
(old-violation-proc signature syntax msg blame)
obj)))
(lambda ()
(let loop ((signatures signatures)
(obj obj))
(if (null? signatures)
(lambda () obj)
(loop (cdr signatures)
(apply-signature (car signatures) obj))))))))))
(delay syntax)))
(define (make-case-signature name cases =? syntax)
(make-signature
name
(lambda (self obj)
(let loop ((cases cases))
(cond
((null? cases)
(signature-violation obj self #f #f)
obj)
((=? (car cases) obj)
obj)
(else
(loop (cdr cases))))))
(delay syntax)
#:arbitrary-promise
(delay (apply arbitrary-one-of =? cases))))
(define signature-key (gensym 'signature-key))
(define-struct procedure-signature-info (arg-signatures return-signature) #:transparent)
(define (make-procedure-signature name arg-signatures return-signature syntax)
(let ((arg-count (length arg-signatures)))
(make-signature
name
(lambda (self thing)
(let-values (((proc blame-syntax)
(if (procedure-to-blame? thing)
(values (procedure-to-blame-proc thing)
(procedure-to-blame-syntax thing))
(values thing #f))))
(cond
((not (procedure? proc))
(signature-violation proc self #f #f)
thing)
((not (procedure-arity-includes? proc arg-count)) ; #### variable arity
(signature-violation proc self parameter-count-mismatch-message #f)
thing)
(else
(attach-name
(object-name proc)
(procedure-reduce-arity
(lambda args
(call-with-immediate-continuation-mark
signature-key
(lambda (maybe)
(if (not (= (length args) arg-count))
(begin
(signature-violation proc self argument-count-mismatch-message #f)
(apply-signature return-signature (apply proc args)))
(let* ((old-violation-proc (signature-violation-proc))
(arg-violation? #f)
(args
(call-with-signature-violation-proc
(lambda (obj signature message blame)
(set! arg-violation? #t)
(old-violation-proc obj signature message blame))
(lambda ()
(map apply-signature arg-signatures args)))))
(if (eq? maybe return-signature)
(apply proc args)
(let ((retval
(with-continuation-mark
signature-key return-signature
(apply proc args))))
(if arg-violation?
retval
(call-with-signature-violation-proc
(lambda (obj signature message _)
;; blame the procedure
(old-violation-proc obj signature message blame-syntax))
(lambda ()
(apply-signature return-signature retval)))))))))))
(procedure-arity proc)))))))
(delay syntax)
#:arbitrary-promise
(delay
(apply lift->arbitrary arbitrary-procedure return-signature arg-signatures))
#:info-promise
(delay
(make-procedure-signature-info arg-signatures return-signature)))))
(define (attach-name name thing)
(if (and (procedure? thing)
(symbol? name))
(procedure-rename thing name)
thing))
; Lazy signature checking for structs
;; This is attached prop:lazy-wrap property of struct types subject to
;; lazy checking.
(define-struct lazy-wrap-info
(constructor
raw-accessors raw-mutators
;; procedures for referencing or setting an additional field within the struct
;; that field contains a list of lists of unchecked field signatures
ref-proc set!-proc))
; value should be a lazy-wrap-info
(define-values (prop:lazy-wrap lazy-wrap? lazy-wrap-ref)
(make-struct-type-property 'lazy-wrap))
; The field accessed by ref-proc and set!-proc contains one of these:
(define-struct lazy-wrap-log
;; list of lazy-log-not-checked
(not-checked
;; list of lists of field signatures
checked)
#:transparent)
; This situation makes trouble:
; (make-mixed-signature (make-lazy-wrap-signature ...) (make-lazy-wrap-signature ...) ...)
; We need to push the `mixed' signature inside the lazy-wrap
; signature, which is why the struct-map signature has an implicit
; `mixed'.
; To this end, a `lazy-log-not-checked' object tracks a list of
; `mixed' alternatives. The `mixed-signature' field tracks from which
; `mixed' contract the mixture has originally come from.
; (It may be #f, in which case the `field-signatures-list' is a one-element list.)
(define-struct lazy-log-not-checked
(mixed-signature field-signatures-list)
#:transparent)
(define (make-lazy-wrap-signature name eager-checking? type-descriptor predicate field-signatures syntax)
(really-make-lazy-wrap-signature name eager-checking?
type-descriptor predicate #f (list field-signatures) syntax))
; The lists of signatures in `field-signatures-list' form an implicit mixed signature.
(define (really-make-lazy-wrap-signature name eager-checking? type-descriptor predicate
mixed-signature field-signatures-list
syntax)
(let ((lazy-wrap-info (lazy-wrap-ref type-descriptor))
(not-checked (make-lazy-log-not-checked mixed-signature field-signatures-list))
(lazy-wrap-signature-info
(make-lazy-wrap-signature-info eager-checking? type-descriptor predicate field-signatures-list)))
(let ((constructor (lazy-wrap-info-constructor lazy-wrap-info))
(raw-accessors (lazy-wrap-info-raw-accessors lazy-wrap-info))
(wrap-ref (lazy-wrap-info-ref-proc lazy-wrap-info))
(wrap-set! (lazy-wrap-info-set!-proc lazy-wrap-info)))
(make-signature
name
(lambda (self thing)
(if (not (predicate thing))
(signature-violation thing self #f #f)
(begin
(let ((log (wrap-ref thing)))
(cond
((not log)
(wrap-set! thing
(make-lazy-wrap-log (list not-checked) '())))
((not (let ()
(define (<=? sigs1 sigs2)
(andmap signature<=? sigs1 sigs2))
(define (check wrap-field-signatures)
(ormap (lambda (field-signatures)
(<=? wrap-field-signatures field-signatures))
field-signatures-list))
(or (ormap (lambda (wrap-not-checked)
(andmap check
(lazy-log-not-checked-field-signatures-list wrap-not-checked)))
(lazy-wrap-log-not-checked log))
(ormap check (lazy-wrap-log-checked log)))))
(wrap-set! thing
(make-lazy-wrap-log (cons not-checked (lazy-wrap-log-not-checked log))
(lazy-wrap-log-checked log))))))
(when eager-checking?
(check-lazy-wraps! type-descriptor thing))))
thing)
(delay syntax)
#:info-promise
(delay lazy-wrap-signature-info)
#:=?-proc
(lambda (this-info other-info)
(and (lazy-wrap-signature-info? other-info)
(lazy-wrap-signature-info-field-signatures-list other-info)
(eq? type-descriptor (lazy-wrap-signature-info-descriptor other-info))
(andmap (lambda (this-field-signatures)
(andmap (lambda (other-field-signatures)
(andmap signature=? this-field-signatures other-field-signatures))
(lazy-wrap-signature-info-field-signatures-list other-info)))
(lazy-wrap-signature-info-field-signatures-list this-info))))
#:<=?-proc
(lambda (this-info other-info)
(and (lazy-wrap-signature-info? other-info)
(lazy-wrap-signature-info-field-signatures-list other-info)
(eq? type-descriptor (lazy-wrap-signature-info-descriptor other-info))
(andmap (lambda (this-field-signatures)
(ormap (lambda (other-field-signatures)
(andmap signature<=? this-field-signatures other-field-signatures))
(lazy-wrap-signature-info-field-signatures-list other-info)))
(lazy-wrap-signature-info-field-signatures-list this-info))))))))
(define-struct lazy-wrap-signature-info (eager-checking? descriptor predicate field-signatures-list) #:transparent)
(define (check-lazy-wraps! descriptor thing)
(let ((lazy-wrap-info (lazy-wrap-ref descriptor)))
(let ((constructor (lazy-wrap-info-constructor lazy-wrap-info))
(raw-accessors (lazy-wrap-info-raw-accessors lazy-wrap-info))
(raw-mutators (lazy-wrap-info-raw-mutators lazy-wrap-info))
(wrap-ref (lazy-wrap-info-ref-proc lazy-wrap-info))
(wrap-set! (lazy-wrap-info-set!-proc lazy-wrap-info)))
(let ((log (wrap-ref thing)))
(when (and log (pair? (lazy-wrap-log-not-checked log)))
(let loop ((field-vals (map (lambda (raw-accessor)
(raw-accessor thing))
raw-accessors))
(now-checked '())
(not-checkeds (lazy-wrap-log-not-checked log)))
(if (null? not-checkeds)
(begin
(for-each (lambda (raw-mutator field-val)
(raw-mutator thing field-val))
raw-mutators field-vals)
(wrap-set! thing
(make-lazy-wrap-log '()
(append now-checked
(lazy-wrap-log-checked log)))))
(let ((not-checked (car not-checkeds)))
(let ((field-signatures-list (lazy-log-not-checked-field-signatures-list not-checked))
(mixed-signature (lazy-log-not-checked-mixed-signature not-checked)))
(if (not mixed-signature) ; one-element list
(loop (map apply-signature (car field-signatures-list) field-vals)
(cons (car field-signatures-list) now-checked)
(cdr not-checkeds))
(let inner ((field-signatures-list field-signatures-list)) ; implicit mixed
(if (null? field-signatures-list)
(signature-violation thing mixed-signature #f #f)
(let map ((sigs (car field-signatures-list))
(field-vals field-vals)
(new-field-vals '()))
(if (null? sigs)
(loop (reverse new-field-vals)
(cons (car field-signatures-list) now-checked)
(cdr not-checkeds))
(check-signature (car sigs)
(car field-vals)
(lambda (new-val)
(map (cdr sigs)
(cdr field-vals)
(cons new-val new-field-vals)))
(lambda ()
(inner (cdr field-signatures-list))))))))))))))))))
; pushes down mixed contracts
(define (fold-lazy-wrap-signatures mixed-signature sigs)
(let ((lazy-wrap-sigs (make-hasheq))) ; maps a type descriptor to signatures
(define (push-down-lazy-wrap-sigs)
(hash-map lazy-wrap-sigs
(lambda (type-desc signatures)
(let* ((sig (car signatures))
(info (real-signature-info (car signatures))))
(really-make-lazy-wrap-signature
(signature-name sig)
(lazy-wrap-signature-info-eager-checking? info)
type-desc
(lazy-wrap-signature-info-predicate info)
mixed-signature
(apply append
(map (lambda (sig)
(lazy-wrap-signature-info-field-signatures-list (real-signature-info sig)))
signatures))
(signature-syntax sig))))))
(let loop ((sigs sigs)
(vanilla-sigs '()))
(if (null? sigs)
(append (push-down-lazy-wrap-sigs)
(reverse vanilla-sigs))
(let* ((sig (car sigs))
(info (real-signature-info sig)))
(if (lazy-wrap-signature-info? info)
(let ((type-desc (lazy-wrap-signature-info-descriptor info)))
(hash-update! lazy-wrap-sigs
type-desc
(lambda (old)
(cons sig old))
(lambda ()
(list sig)))
(loop (cdr sigs) vanilla-sigs))
(loop (cdr sigs) (cons sig vanilla-sigs))))))))
(define checked-pair-table (make-weak-hasheq))
(define-struct checked-pair
(car cdr log)
#:mutable)
(define (checked-pair-access checked-access raw-access)
(lambda (p)
(cond
((hash-ref checked-pair-table
p
(lambda () #f))
=> (lambda (eph)
(checked-access (ephemeron-value eph))))
(else (raw-access p)))))
(define checked-raw-car (checked-pair-access checked-pair-car car))
(define checked-raw-cdr (checked-pair-access checked-pair-cdr cdr))
(define checked-raw-first (checked-pair-access checked-pair-car first))
(define checked-raw-rest (checked-pair-access checked-pair-cdr rest))
(define (checked-raw-set! checked-set!)
(lambda (p new)
(cond
((hash-ref checked-pair-table
p
(lambda () #f))
=> (lambda (eph)
(checked-set! (ephemeron-value eph) new)))
(else
(let ((cp (make-checked-pair (car p) (cdr p) #f)))
(checked-set! cp new)
(hash-set! checked-pair-table p (make-ephemeron p cp)))))))
(define checked-raw-set-car! (checked-raw-set! set-checked-pair-car!))
(define checked-raw-set-cdr! (checked-raw-set! set-checked-pair-cdr!))
(define (checked-pair-get-log p)
(cond
((hash-ref checked-pair-table
p
(lambda () #f))
=> (lambda (eph)
(checked-pair-log (ephemeron-value eph))))
(else #f)))
(define (checked-pair-set-log! p new)
(cond
((hash-ref checked-pair-table
p
(lambda () #f))
=> (lambda (eph)
(set-checked-pair-log! (ephemeron-value eph) new)))
(else
(hash-set! checked-pair-table p
(make-ephemeron p
(make-checked-pair (car p) (cdr p) new))))))
(define checked-pair-lazy-wrap-info
(make-lazy-wrap-info cons
(list checked-raw-car checked-raw-cdr)
(list checked-raw-set-car! checked-raw-set-cdr!)
checked-pair-get-log
checked-pair-set-log!))
(define checked-pair-descriptor
(call-with-values
(lambda ()
(make-struct-type 'dummy-checked-pair #f 0 0 #f
(list
(cons prop:lazy-wrap checked-pair-lazy-wrap-info))))
(lambda (desc . _)
desc)))
(define (make-pair-signature eager-checking? car-sig cdr-sig)
(make-lazy-wrap-signature 'pair eager-checking?
checked-pair-descriptor pair? (list car-sig cdr-sig) #'pair))
(define (checked-car p)
(car p)
(check-lazy-wraps! checked-pair-descriptor p)
(checked-raw-car p))
(define (checked-cdr p)
(cdr p)
(check-lazy-wraps! checked-pair-descriptor p)
(checked-raw-cdr p))
(define (checked-first p)
(first p)
(check-lazy-wraps! checked-pair-descriptor p)
(checked-raw-first p))
(define (checked-rest p)
(rest p)
(check-lazy-wraps! checked-pair-descriptor p)
(checked-raw-rest p))
)