Skip to content

Commit

Permalink
disallow unbalanced bidirectional formatting in strings and comments
Browse files Browse the repository at this point in the history
  • Loading branch information
@JeffBezanson
JeffBezanson committed Nov 3, 2021
1 parent 79b0226 commit 9f10661
Show file tree
Hide file tree
Showing 2 changed files with 71 additions and 42 deletions.
104 changes: 62 additions & 42 deletions src/julia-parser.scm
View file
Original file line number Diff line number Diff line change
Expand Up @@ -221,13 +221,6 @@

(define (newline? c) (eqv? c #\newline))

(define (skip-to-eol port)
(let ((c (peek-char port)))
(cond ((eof-object? c) c)
((eqv? c #\newline) c)
(else (read-char port)
(skip-to-eol port)))))

(define (op-or-sufchar? c) (or (op-suffix-char? c) (opchar? c)))

(define (read-operator port c0 (postfix? #f))
Expand Down Expand Up @@ -495,33 +488,56 @@
(pair? (cadr t)) (eq? (car (cadr t)) 'core)
(memq (cadadr t) '(@int128_str @uint128_str @big_str))))

(define (make-bidi-state) '(0 . 0))

(define (update-bidi-state st c)
(case c
((#\U202A #\U202B #\U202D #\U202E) (cons (+ (car st) 1) (cdr st))) ;; LRE RLE LRO RLO
((#\U2066 #\U2067 #\U2068) (cons (car st) (+ (cdr st) 1))) ;; LRI RLI FSI
((#\U202C) (cons (- (car st) 1) (cdr st))) ;; PDF
((#\U2069) (cons (car st) (- (cdr st) 1))) ;; PDI
((#\newline) '(0 . 0))
(else st)))

(define (bidi-state-terminated? st) (equal? st '(0 . 0)))

(define (skip-line-comment port)
(let ((c (peek-char port)))
(cond ((eof-object? c) c)
((eqv? c #\newline) c)
(else (read-char port)
(skip-line-comment port)))))

(define (skip-multiline-comment port count bds)
(let ((c (read-char port)))
(if (eof-object? c)
(error "incomplete: unterminated multi-line comment #= ... =#") ; NOTE: changing this may affect code in base/client.jl
(if (eqv? c #\=)
(let ((c (peek-char port)))
(if (eqv? c #\#)
(begin
(read-char port)
(if (> count 1)
(skip-multiline-comment port (- count 1) bds)
(if (not (bidi-state-terminated? bds))
(error "unbalanced bidirectional formatting in comment"))))
(skip-multiline-comment port count (update-bidi-state bds c))))
(if (eqv? c #\#)
(skip-multiline-comment port
(if (eqv? (peek-char port) #\=)
(begin (read-char port)
(+ count 1))
count)
bds)
(skip-multiline-comment port count (update-bidi-state bds c)))))))

;; skip to end of comment, starting at #: either #...<eol> or #= .... =#.
(define (skip-comment port)
(define (skip-multiline-comment port count)
(let ((c (read-char port)))
(if (eof-object? c)
(error "incomplete: unterminated multi-line comment #= ... =#") ; NOTE: changing this may affect code in base/client.jl
(begin (if (eqv? c #\=)
(let ((c (peek-char port)))
(if (eqv? c #\#)
(begin
(read-char port)
(if (> count 1)
(skip-multiline-comment port (- count 1))))
(skip-multiline-comment port count)))
(if (eqv? c #\#)
(skip-multiline-comment port
(if (eqv? (peek-char port) #\=)
(begin (read-char port)
(+ count 1))
count))
(skip-multiline-comment port count)))))))

(read-char port) ; read # that was already peeked
(if (eqv? (peek-char port) #\=)
(begin (read-char port) ; read initial =
(skip-multiline-comment port 1))
(skip-to-eol port)))
(skip-multiline-comment port 1 (make-bidi-state)))
(skip-line-comment port)))

(define (skip-ws-and-comments port)
(skip-ws port #t)
Expand Down Expand Up @@ -2354,24 +2370,28 @@
(let loop ((c (read-char p))
(b (open-output-string))
(e ())
(quotes 0))
(quotes 0)
(bds (make-bidi-state)))
(cond
((eqv? c delim)
(if (< quotes n)
(loop (read-char p) b e (+ quotes 1))
(reverse (cons (io.tostring! b) e))))
(loop (read-char p) b e (+ quotes 1) bds)
(begin
(if (not (bidi-state-terminated? bds))
(error "unbalanced bidirectional formatting in string literal"))
(reverse (cons (io.tostring! b) e)))))

((= quotes 1)
(if (not raw) (write-char #\\ b))
(write-char delim b)
(loop c b e 0))
(loop c b e 0 (update-bidi-state bds c)))

((= quotes 2)
(if (not raw) (write-char #\\ b))
(write-char delim b)
(if (not raw) (write-char #\\ b))
(write-char delim b)
(loop c b e 0))
(loop c b e 0 (update-bidi-state bds c)))

((eqv? c #\\)
(if raw
Expand All @@ -2384,19 +2404,19 @@
(io.write b (string.rep "\\" (div count 2)))
(if (odd? count)
(begin (write-char delim b)
(loop (read-char p) b e 0))
(loop nxch b e 0)))
(loop (read-char p) b e 0 bds))
(loop nxch b e 0 bds)))
(else
(io.write b (string.rep "\\" count))
(write-char nxch b)
(loop (read-char p) b e 0))))
(loop (read-char p) b e 0 (update-bidi-state bds nxch)))))
(let ((nxch (not-eof-for delim (read-char p))))
(write-char #\\ b)
(if (eqv? nxch #\return)
(loop nxch b e 0)
(loop nxch b e 0 bds)
(begin
(write-char nxch b)
(loop (read-char p) b e 0))))))
(loop (read-char p) b e 0 (update-bidi-state bds nxch)))))))

((and (eqv? c #\$) (not raw))
(let* ((ex (parse-interpolate s))
Expand All @@ -2406,19 +2426,19 @@
(loop (read-char p)
(open-output-string)
(list* ex (io.tostring! b) e)
0)))
0 bds)))

; convert literal \r and \r\n in strings to \n (issue #11988)
((eqv? c #\return) ; \r
(begin
(if (eqv? (peek-char p) #\linefeed) ; \r\n
(read-char p))
(write-char #\newline b)
(loop (read-char p) b e 0)))
(loop (read-char p) b e 0 bds)))

(else
(write-char (not-eof-for delim c) b)
(loop (read-char p) b e 0)))))
(loop (read-char p) b e 0 (update-bidi-state bds c))))))

(define (not-eof-1 c)
(if (eof-object? c)
Expand Down
9 changes: 9 additions & 0 deletions test/syntax.jl
View file
Original file line number Diff line number Diff line change
Expand Up @@ -3060,3 +3060,12 @@ end
@test err == 5 + 6
@test x == 1
end

@test_throws ParseError Meta.parse("""
function checkUserAccess(u::User)
if u.accessLevel != "user\u202e \u2066# users are not allowed\u2069\u2066"
return true
end
return false
end
""")

0 comments on commit 9f10661

Please sign in to comment.