racket/collects/tests/stxparse/select.rkt
2010-05-17 12:07:32 -04:00

89 lines
2.3 KiB
Racket

#lang scheme
(require rackunit
syntax/parse)
(require (for-syntax syntax/parse))
(provide (all-defined-out))
;; Error selection tests
(error-print-source-location #f)
(define-syntax-rule (terx s p stuff ...)
(terx* s [p] stuff ...))
(define-syntax terx*
(syntax-parser
[(terx s [p ...] (~optional (~seq #:term term) #:defaults ([term #'#f])) rx ...)
#'(test-case (format "line ~s: ~a match ~s for error"
(syntax-line (quote-syntax s))
's '(p ...))
(let ([exn (let/ec escape
(check-exn (lambda (exn)
(escape exn))
(lambda ()
(syntax-parse (quote-syntax s)
[p 'ok] ...))))])
(let ([msg (exn-message exn)]
[stxs (and (exn:fail:syntax? exn)
(exn:fail:syntax-exprs exn))])
(when 'term
(check-equal? (and (pair? stxs) (syntax->datum (car stxs))) 'term))
(erx rx (exn-message exn)) ... #t))
'ok)]))
(define-syntax erx
(syntax-rules (not)
[(erx (not rx) msg)
(check (compose not regexp-match?) rx msg)]
[(erx rx msg)
(check regexp-match? rx msg)]))
;; ----
(terx* (1 2) [x:nat (y:id z:id)]
#:term 1
#rx"expected identifier")
;; --
(define-syntax-class bindings
(pattern ((var:id rhs:expr) ...)))
(terx* ((x 1 2)) [x:id bs:bindings]
#:term 2
#rx"unexpected term")
;; --
(terx ((a 1) (a 2))
((~or (~once ((~datum a) x) #:name "A clause")
(~optional ((~datum b) y) #:name "B clause"))
...)
;; #:term (a 2)
#rx"too many occurrences of A clause")
;; --
(define-syntax-class A
(pattern ((~datum a) x)))
(define-syntax-class B
(pattern ((~datum b) y)))
(terx ((a 1) (a 2))
((~or (~once a:A #:name "A clause")
(~optional b:B #:name "B clause"))
...)
#rx"too many occurrences of A clause")
(terx ((a 1 2) _)
((~or (~once a:A #:name "A clause")
(~optional b:B #:name "B clause"))
...)
#rx"unexpected term")
(terx ((b 1 2) _)
((~or (~once a:A #:name "A clause")
(~optional b:B #:name "B clause"))
...)
#rx"unexpected term")