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| author | Philipp Stephani <phst@google.com> | 2016-10-24 21:54:51 +0200 |
|---|---|---|
| committer | Philipp Stephani <phst@google.com> | 2017-01-01 13:24:14 +0100 |
| commit | 93be35e038bbb19e8d64d3c1f9d1be76a9083d09 (patch) | |
| tree | 7a9074fa83d51aa8136f57be267c83016c4f3978 | |
| parent | baa370f255d2f9d3f662fac0de98eaadd3242aa6 (diff) | |
| download | emacs-93be35e038bbb19e8d64d3c1f9d1be76a9083d09.tar.gz emacs-93be35e038bbb19e8d64d3c1f9d1be76a9083d09.tar.bz2 emacs-93be35e038bbb19e8d64d3c1f9d1be76a9083d09.zip | |
Fix encoding of JSON surrogate pairs
JSON requires that such pairs be treated as UTF-16 surrogate pairs, not
individual code points; cf. Bug #24784.
* lisp/json.el (json-read-escaped-char): Fix decoding of surrogate
pairs.
(json--decode-utf-16-surrogates): New defun.
* test/lisp/json-tests.el (test-json-read-string): Add test for
surrogate pairs.
| -rw-r--r-- | lisp/json.el | 15 | ||||
| -rw-r--r-- | test/lisp/json-tests.el | 3 |
2 files changed, 18 insertions, 0 deletions
diff --git a/lisp/json.el b/lisp/json.el index 38f828e8fbb..b2ac356641b 100644 --- a/lisp/json.el +++ b/lisp/json.el @@ -363,6 +363,10 @@ representation will be parsed correctly." ;; String parsing +(defun json--decode-utf-16-surrogates (high low) + "Return the code point represented by the UTF-16 surrogates HIGH and LOW." + (+ (lsh (- high #xD800) 10) (- low #xDC00) #x10000)) + (defun json-read-escaped-char () "Read the JSON string escaped character at point." ;; Skip over the '\' @@ -372,6 +376,17 @@ representation will be parsed correctly." (cond (special (cdr special)) ((not (eq char ?u)) char) + ;; Special-case UTF-16 surrogate pairs, + ;; cf. https://tools.ietf.org/html/rfc7159#section-7. Note that + ;; this clause overlaps with the next one and therefore has to + ;; come first. + ((looking-at + (rx (group (any "Dd") (any "89ABab") (= 2 (any "0-9A-Fa-f"))) + "\\u" (group (any "Dd") (any "C-Fc-f") (= 2 (any "0-9A-Fa-f"))))) + (json-advance 10) + (json--decode-utf-16-surrogates + (string-to-number (match-string 1) 16) + (string-to-number (match-string 2) 16))) ((looking-at "[0-9A-Fa-f][0-9A-Fa-f][0-9A-Fa-f][0-9A-Fa-f]") (let ((hex (match-string 0))) (json-advance 4) diff --git a/test/lisp/json-tests.el b/test/lisp/json-tests.el index 66fc25ad1c0..38672de0664 100644 --- a/test/lisp/json-tests.el +++ b/test/lisp/json-tests.el @@ -167,6 +167,9 @@ Point is moved to beginning of the buffer." (should (equal (json-read-string) "abcαβγ"))) (json-tests--with-temp-buffer "\"\\nasd\\u0444\\u044b\\u0432fgh\\t\"" (should (equal (json-read-string) "\nasdфывfgh\t"))) + ;; Bug#24784 + (json-tests--with-temp-buffer "\"\\uD834\\uDD1E\"" + (should (equal (json-read-string) "\U0001D11E"))) (json-tests--with-temp-buffer "foo" (should-error (json-read-string) :type 'json-string-format))) |