GNU bug report logs - #22983
syntax-ppss returns wrong result.

Previous Next

Full log

Message #47 received at 22983 <at> debbugs.gnu.org (full text, mbox):

From: Dmitry Gutov <dgutov <at> yandex.ru>
To: Alan Mackenzie <acm <at> muc.de>, 22983 <at> debbugs.gnu.org
Subject: Re: bug#22983: syntax-ppss returns wrong result.
Date: Fri, 18 Mar 2016 02:49:34 +0200

On 03/11/2016 05:15 PM, Alan Mackenzie wrote:

This patch should make ppss-0 and ppss-1 match:

diff --git a/lisp/emacs-lisp/syntax.el b/lisp/emacs-lisp/syntax.el
index e20a210..c1b9d84 100644
--- a/lisp/emacs-lisp/syntax.el
+++ b/lisp/emacs-lisp/syntax.el
@@ -371,6 +371,11 @@ syntax-ppss-max-span
 We try to make sure that cache entries are at least this far apart
 from each other, to avoid keeping too much useless info.")

+(defvar syntax-ppss-dont-widen nil
+  "If non-nil, `syntax-ppss' will work on the non-widened buffer.
+The code that uses this should create local bindings for
+`syntax-ppss-cache' and `syntax-ppss-last' too.")
+
 (defvar syntax-begin-function nil
   "Function to move back outside of any comment/string/paren.
 This function should move the cursor back to some syntactically safe
@@ -423,12 +428,21 @@ syntax-ppss
 in the returned list (counting from 0) cannot be relied upon.
 Point is at POS when this function returns.

+IF `syntax-ppss-dont-widen' is nil, the buffer is temporarily
+widened.
+
 It is necessary to call `syntax-ppss-flush-cache' explicitly if
 this function is called while `before-change-functions' is
 temporarily let-bound, or if the buffer is modified without
 running the hook."
   ;; Default values.
   (unless pos (setq pos (point)))
+  (save-restriction
+    (unless syntax-ppss-dont-widen
+      (widen))
+    (syntax-pps--at pos)))
+
+(defun syntax-ppss--at (pos)
   (syntax-propertize pos)
   ;;
   (let ((old-ppss (cdr syntax-ppss-last))

Previous Next

GNU bug tracking system
Copyright (C) 1999 Darren O. Benham, 1997,2003 nCipher Corporation Ltd, 1994-97 Ian Jackson.