GNU bug report logs - #13541
24.2.92; awk-mode: wrong font locking regexp literals

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Message #5 received at submit <at> debbugs.gnu.org (full text, mbox):

From: Leo Liu <sdl.web <at> gmail.com>
To: bug-gnu-emacs <at> gnu.org
Subject: 24.2.92; awk-mode: wrong font locking regexp literals
Date: Thu, 24 Jan 2013 19:43:06 +0800

[Message part 1 (text/plain, inline)]

In an awk buffer having the following text:

#--BEGIN--
NF { /xyz/ }

NF {
    /xyz/
}
#--END--

I have the second regexp properly font-locked but not the first one.

(tested in GNU Emacs 24.2.92.1 of 2013-01-13)

[awk-mode-bug.png (image/png, inline)]

[Message part 3 (text/plain, inline)]

Leo

Message #8 received at 13541 <at> debbugs.gnu.org (full text, mbox):

From: Glenn Morris <rgm <at> gnu.org>
To: Leo Liu <sdl.web <at> gmail.com>
Cc: bug-cc-mode <at> gnu.org, 13541 <at> debbugs.gnu.org
Subject: Re: bug#13541: 24.2.92; awk-mode: wrong font locking regexp literals
Date: Thu, 24 Jan 2013 13:28:33 -0500

Leo Liu wrote:

> In an awk buffer having the following text:
>
> #--BEGIN--
> NF { /xyz/ }
>
> NF {
>     /xyz/
> }
> #--END--
>
> I have the second regexp properly font-locked but not the first one.

Do you have an example of an actual useful awk script showing the issue,
because this one seems like a pointless no-op?

Message #11 received at 13541 <at> debbugs.gnu.org (full text, mbox):

From: Alan Mackenzie <acm <at> muc.de>
To: Glenn Morris <rgm <at> gnu.org>
Cc: bug-cc-mode <at> gnu.org, Leo Liu <sdl.web <at> gmail.com>, 13541 <at> debbugs.gnu.org
Subject: Re: bug#13541: 24.2.92; awk-mode: wrong font locking regexp literals
Date: Thu, 24 Jan 2013 22:16:04 +0000

Hi, Glenn,

On Thu, Jan 24, 2013 at 01:28:33PM -0500, Glenn Morris wrote:
> Leo Liu wrote:

> > In an awk buffer having the following text:

> > #--BEGIN--
> > NF { /xyz/ }

> > NF {
> >     /xyz/
> > }
> > #--END--

> > I have the second regexp properly font-locked but not the first one.

> Do you have an example of an actual useful awk script showing the issue,
> because this one seems like a pointless no-op?

This is a real bug, perhaps not a difficult one.  "/regexp/" is an
expression with value 1 iff the current input line matches the regexp.
So a line like

    NF { print /xyz/ }

is perfectly legitimate, printing 1 if there's an "xyz" on the line.

I'm looking at this bug at the moment.

-- 
Alan Mackenzie (Nuremberg, Germany).

Message #14 received at 13541 <at> debbugs.gnu.org (full text, mbox):

From: Leo Liu <sdl.web <at> gmail.com>
To: Alan Mackenzie <acm <at> muc.de>
Cc: Glenn Morris <rgm <at> gnu.org>, 13541 <at> debbugs.gnu.org
Subject: Re: bug#13541: 24.2.92; awk-mode: wrong font locking regexp literals
Date: Fri, 25 Jan 2013 09:20:19 +0800

On 2013-01-25 06:16 +0800, Alan Mackenzie wrote:
> This is a real bug, perhaps not a difficult one.  "/regexp/" is an
> expression with value 1 iff the current input line matches the regexp.
> So a line like
>
>     NF { print /xyz/ }
>
> is perfectly legitimate, printing 1 if there's an "xyz" on the line.
>
> I'm looking at this bug at the moment.

Thanks to all for chiming in.

Alan, I also have another seemingly buglet about indentation.

Every line after a pattern-action pair like the following one (where
action is omitted) is indented to column 4, i.e. it doesn't recognise a
newline terminates a pattern.

$0 == "Emacs"
    |
    all following lines indented here

(this might be regression, I seem to recall reporting something along
these lines some while ago.)

Leo

Message #17 received at 13541 <at> debbugs.gnu.org (full text, mbox):

From: Glenn Morris <rgm <at> gnu.org>
To: Leo Liu <sdl.web <at> gmail.com>
Cc: Alan Mackenzie <acm <at> muc.de>, 13541 <at> debbugs.gnu.org
Subject: Re: bug#13541: 24.2.92; awk-mode: wrong font locking regexp literals
Date: Thu, 24 Jan 2013 20:33:31 -0500

Leo Liu wrote:

> (this might be regression, I seem to recall reporting something along
> these lines some while ago.)

No, it is the never addressed

http://debbugs.gnu.org/12274

Message #20 received at 13541 <at> debbugs.gnu.org (full text, mbox):

From: Glenn Morris <rgm <at> gnu.org>
To: Leo Liu <sdl.web <at> gmail.com>
Cc: Alan Mackenzie <acm <at> muc.de>, 13541 <at> debbugs.gnu.org
Subject: Re: bug#13541: 24.2.92; awk-mode: wrong font locking regexp literals
Date: Thu, 24 Jan 2013 20:44:36 -0500

> Leo Liu wrote:
>
>> (this might be regression,

PS henceforth it is prohibited to use the word "regression" except in
the form "this is a regression against Emacs XX.YY, where it works as
desired".

Message #23 received at 13541 <at> debbugs.gnu.org (full text, mbox):

From: Alan Mackenzie <acm <at> muc.de>
To: Leo Liu <sdl.web <at> gmail.com>
Cc: bug-cc-mode <at> gnu.org, Glenn Morris <rgm <at> gnu.org>, 13541 <at> debbugs.gnu.org
Subject: Re: bug#13541: 24.2.92; awk-mode: wrong font locking regexp literals
Date: Fri, 25 Jan 2013 17:50:57 +0000

Hi, Leo.

On Thu, Jan 24, 2013 at 07:43:06PM +0800, Leo Liu wrote:
> In an awk buffer having the following text:

> #--BEGIN--
> NF { /xyz/ }

> NF {
>     /xyz/
> }
> #--END--

> I have the second regexp properly font-locked but not the first one.

Yes.

Could you please try out, fairly thoroughly, the following patch, and let
me know how it goes.  It aims to fontify a /regexp/ wherever one might
occur.




=== modified file 'lisp/progmodes/cc-awk.el'
*** lisp/progmodes/cc-awk.el	2013-01-01 09:11:05 +0000
--- lisp/progmodes/cc-awk.el	2013-01-25 17:47:38 +0000
***************
*** 211,217 ****
  ;; division sign.
  (defconst c-awk-neutral-re
  ;  "\\([{}@` \t]\\|\\+\\+\\|--\\|\\\\.\\)+") ; changed, 2003/6/7
!   "\\([{}@` \t]\\|\\+\\+\\|--\\|\\\\.\\)")
  ;;   A "neutral" char(pair).  Doesn't change the "state" of a subsequent /.
  ;; This is space/tab, braces, an auto-increment/decrement operator or an
  ;; escaped character.  Or one of the (invalid) characters @ or `.  But NOT an
--- 211,217 ----
  ;; division sign.
  (defconst c-awk-neutral-re
  ;  "\\([{}@` \t]\\|\\+\\+\\|--\\|\\\\.\\)+") ; changed, 2003/6/7
!   "\\([}@` \t]\\|\\+\\+\\|--\\|\\\\\\(.\\|[\n\r]\\)\\)")
  ;;   A "neutral" char(pair).  Doesn't change the "state" of a subsequent /.
  ;; This is space/tab, braces, an auto-increment/decrement operator or an
  ;; escaped character.  Or one of the (invalid) characters @ or `.  But NOT an
***************
*** 231,237 ****
  ;; will only work when there won't be a preceding " or / before the sought /
  ;; to foul things up.
  (defconst c-awk-non-arith-op-bra-re
!   "[[\(&=:!><,?;'~|]")
  ;;   Matches an opening BRAcket, round or square, or any operator character
  ;; apart from +,-,/,*,%.  For the purpose at hand (detecting a / which is a
  ;; regexp bracket) these arith ops are unnecessary and a pain, because of "++"
--- 231,237 ----
  ;; will only work when there won't be a preceding " or / before the sought /
  ;; to foul things up.
  (defconst c-awk-non-arith-op-bra-re
!   "[[\({&=:!><,?;'~|]")
  ;;   Matches an opening BRAcket, round or square, or any operator character
  ;; apart from +,-,/,*,%.  For the purpose at hand (detecting a / which is a
  ;; regexp bracket) these arith ops are unnecessary and a pain, because of "++"
***************
*** 242,247 ****
--- 242,257 ----
  ;; bracket, in a context where an immediate / would be a division sign.  This
  ;; will only work when there won't be a preceding " or / before the sought /
  ;; to foul things up.
+ (defconst c-awk-pre-exp-alphanum-kwd-re
+   (concat "\\(^\\|[^_\n\r]\\)\\<"
+ 	  (regexp-opt '("print" "return" "case") t)
+ 	  "\\>\\([^_\n\r]\\|$\\)"))
+ ;;   Matches all AWK keywords which can precede expressions (including
+ ;; /regexp/).
+ (defconst c-awk-kwd-regexp-sign-re
+   (concat c-awk-pre-exp-alphanum-kwd-re c-awk-neutrals*-re "/"))
+ ;;   Matches a piece of AWK buffer ending in <kwd> /, where <kwd> is a keyword
+ ;; which can precede an expression.
  
  ;; REGEXPS USED FOR FINDING THE POSITION OF A "virtual semicolon"
  (defconst c-awk-_-harmless-nonws-char-re "[^#/\"\\\\\n\r \t]")
***************
*** 721,729 ****
      (goto-char anchor)
      ;; Analyze the line to find out what the / is.
      (if (if anchor-state-/div
!             (not (search-forward-regexp c-awk-regexp-sign-re (1+ /point) t))
!           (search-forward-regexp c-awk-div-sign-re (1+ /point) t))
!         ;; A division sign.
  	(progn (goto-char (1+ /point)) nil)
        ;; A regexp opener
        ;; Jump over the regexp innards, setting the match data.
--- 731,740 ----
      (goto-char anchor)
      ;; Analyze the line to find out what the / is.
      (if (if anchor-state-/div
! 	    (not (search-forward-regexp c-awk-regexp-sign-re (1+ /point) t))
! 	  (and (not (search-forward-regexp c-awk-kwd-regexp-sign-re (1+ /point) t))
! 	       (search-forward-regexp c-awk-div-sign-re (1+ /point) t)))
! 	;; A division sign.
  	(progn (goto-char (1+ /point)) nil)
        ;; A regexp opener
        ;; Jump over the regexp innards, setting the match data.


> Leo

-- 
Alan Mackenzie (Nuremberg, Germany).

Message #26 received at 13541 <at> debbugs.gnu.org (full text, mbox):

From: Richard Stallman <rms <at> gnu.org>
To: Glenn Morris <rgm <at> gnu.org>
Cc: acm <at> muc.de, sdl.web <at> gmail.com, 13541 <at> debbugs.gnu.org
Subject: Re: bug#13541: 24.2.92; awk-mode: wrong font locking regexp literals
Date: Fri, 25 Jan 2013 16:32:50 -0500

If a a nasty and cruel bug appears just before the release, is that
"regression to the mean"?

-- 
Dr Richard Stallman
President, Free Software Foundation
51 Franklin St
Boston MA 02110
USA
www.fsf.org  www.gnu.org
Skype: No way! That's nonfree (freedom-denying) software.
  Use Ekiga or an ordinary phone call

Message #29 received at 13541 <at> debbugs.gnu.org (full text, mbox):

From: Leo Liu <sdl.web <at> gmail.com>
To: Alan Mackenzie <acm <at> muc.de>
Cc: 13541 <at> debbugs.gnu.org
Subject: Re: bug#13541: 24.2.92; awk-mode: wrong font locking regexp literals
Date: Sat, 26 Jan 2013 19:14:49 +0800

On 2013-01-26 01:50 +0800, Alan Mackenzie wrote:
> Could you please try out, fairly thoroughly, the following patch, and let
> me know how it goes.  It aims to fontify a /regexp/ wherever one might
> occur.

The second regexp is not font-locked in this case:

/a/ { print /abc/ }

Leo

Message #32 received at 13541 <at> debbugs.gnu.org (full text, mbox):

From: Alan Mackenzie <acm <at> muc.de>
To: Leo Liu <sdl.web <at> gmail.com>
Cc: 13541 <at> debbugs.gnu.org
Subject: Re: bug#13541: 24.2.92; awk-mode: wrong font locking regexp literals
Date: Sun, 27 Jan 2013 18:59:06 +0000

Hi, Leo.

On Sat, Jan 26, 2013 at 07:14:49PM +0800, Leo Liu wrote:
> On 2013-01-26 01:50 +0800, Alan Mackenzie wrote:
> > Could you please try out, fairly thoroughly, the following patch, and let
> > me know how it goes.  It aims to fontify a /regexp/ wherever one might
> > occur.

> The second regexp is not font-locked in this case:

> /a/ { print /abc/ }

Yes, thanks for spotting this.  The situation was more complicated than I
thought.  I think this replacement patch fixes that case (together with a
few others).  Would you try it out again, please.



=== modified file 'lisp/progmodes/cc-awk.el'
*** lisp/progmodes/cc-awk.el	2013-01-01 09:11:05 +0000
--- lisp/progmodes/cc-awk.el	2013-01-27 18:23:59 +0000
***************
*** 127,148 ****
  ;; escaped EOL.
  
  ;; REGEXPS FOR "HARMLESS" STRINGS/LINES.
- (defconst c-awk-harmless-char-re "[^_#/\"\\\\\n\r]")
- ;;   Matches any character but a _, #, /, ", \, or newline.  N.B. _" starts a
- ;; localization string in gawk 3.1
  (defconst c-awk-harmless-_ "_\\([^\"]\\|\\'\\)")
  ;;   Matches an underline NOT followed by ".
  (defconst c-awk-harmless-string*-re
    (concat "\\(" c-awk-harmless-char-re "\\|" c-awk-esc-pair-re "\\|" c-awk-harmless-_ "\\)*"))
! ;;   Matches a (possibly empty) sequence of chars without unescaped /, ", \,
! ;; #, or newlines.
  (defconst c-awk-harmless-string*-here-re
    (concat "\\=" c-awk-harmless-string*-re))
! ;; Matches the (possibly empty) sequence of chars without unescaped /, ", \,
! ;; at point.
  (defconst c-awk-harmless-line-re
!   (concat c-awk-harmless-string*-re
!           "\\(" c-awk-comment-without-nl "\\)?" c-awk-nl-or-eob))
  ;;   Matches (the tail of) an AWK \"logical\" line not containing an unescaped
  ;; " or /.  "logical" means "possibly containing escaped newlines".  A comment
  ;; is matched as part of the line even if it contains a " or a /.  The End of
--- 127,155 ----
  ;; escaped EOL.
  
  ;; REGEXPS FOR "HARMLESS" STRINGS/LINES.
  (defconst c-awk-harmless-_ "_\\([^\"]\\|\\'\\)")
  ;;   Matches an underline NOT followed by ".
+ (defconst c-awk-harmless-char-re "[^_#/\"{}();\\\\\n\r]")
+ ;;   Mathches any character not significant in the state machine applying
+ ;; syntax-table properties to "s and /s.
  (defconst c-awk-harmless-string*-re
    (concat "\\(" c-awk-harmless-char-re "\\|" c-awk-esc-pair-re "\\|" c-awk-harmless-_ "\\)*"))
! ;;   Matches a (possibly empty) sequence of characters insignificant in the
! ;; state machine applying syntax-table properties to "s and /s.
  (defconst c-awk-harmless-string*-here-re
    (concat "\\=" c-awk-harmless-string*-re))
! ;; Matches the (possibly empty) sequence of "insignificant" chars at point.
! 
! (defconst c-awk-harmless-line-char-re "[^_#/\"\\\\\n\r]")
! ;;   Matches any character but a _, #, /, ", \, or newline.  N.B. _" starts a
! ;; localisation string in gawk 3.1
! (defconst c-awk-harmless-line-string*-re
!   (concat "\\(" c-awk-harmless-line-char-re "\\|" c-awk-esc-pair-re "\\|" c-awk-harmless-_ "\\)*"))
! ;;   Matches a (possibly empty) sequence of chars without unescaped /, ", \,
! ;; #, or newlines.
  (defconst c-awk-harmless-line-re
!   (concat c-awk-harmless-line-string*-re
! 	  "\\(" c-awk-comment-without-nl "\\)?" c-awk-nl-or-eob))
  ;;   Matches (the tail of) an AWK \"logical\" line not containing an unescaped
  ;; " or /.  "logical" means "possibly containing escaped newlines".  A comment
  ;; is matched as part of the line even if it contains a " or a /.  The End of
***************
*** 211,217 ****
  ;; division sign.
  (defconst c-awk-neutral-re
  ;  "\\([{}@` \t]\\|\\+\\+\\|--\\|\\\\.\\)+") ; changed, 2003/6/7
!   "\\([{}@` \t]\\|\\+\\+\\|--\\|\\\\.\\)")
  ;;   A "neutral" char(pair).  Doesn't change the "state" of a subsequent /.
  ;; This is space/tab, braces, an auto-increment/decrement operator or an
  ;; escaped character.  Or one of the (invalid) characters @ or `.  But NOT an
--- 218,224 ----
  ;; division sign.
  (defconst c-awk-neutral-re
  ;  "\\([{}@` \t]\\|\\+\\+\\|--\\|\\\\.\\)+") ; changed, 2003/6/7
!   "\\([}@` \t]\\|\\+\\+\\|--\\|\\\\\\(.\\|[\n\r]\\)\\)")
  ;;   A "neutral" char(pair).  Doesn't change the "state" of a subsequent /.
  ;; This is space/tab, braces, an auto-increment/decrement operator or an
  ;; escaped character.  Or one of the (invalid) characters @ or `.  But NOT an
***************
*** 231,238 ****
  ;; will only work when there won't be a preceding " or / before the sought /
  ;; to foul things up.
  (defconst c-awk-non-arith-op-bra-re
!   "[[\(&=:!><,?;'~|]")
! ;;   Matches an opening BRAcket, round or square, or any operator character
  ;; apart from +,-,/,*,%.  For the purpose at hand (detecting a / which is a
  ;; regexp bracket) these arith ops are unnecessary and a pain, because of "++"
  ;; and "--".
--- 238,245 ----
  ;; will only work when there won't be a preceding " or / before the sought /
  ;; to foul things up.
  (defconst c-awk-non-arith-op-bra-re
!   "[[\({&=:!><,?;'~|]")
! ;;   Matches an openeing BRAcket ,round or square, or any operator character
  ;; apart from +,-,/,*,%.  For the purpose at hand (detecting a / which is a
  ;; regexp bracket) these arith ops are unnecessary and a pain, because of "++"
  ;; and "--".
***************
*** 242,247 ****
--- 249,264 ----
  ;; bracket, in a context where an immediate / would be a division sign.  This
  ;; will only work when there won't be a preceding " or / before the sought /
  ;; to foul things up.
+ (defconst c-awk-pre-exp-alphanum-kwd-re
+   (concat "\\(^\\|[^_\n\r]\\)\\<"
+ 	  (regexp-opt '("print" "return" "case") t)
+ 	  "\\>\\([^_\n\r]\\|$\\)"))
+ ;;   Matches all AWK keywords which can precede expressions (including
+ ;; /regexp/).
+ (defconst c-awk-kwd-regexp-sign-re
+   (concat c-awk-pre-exp-alphanum-kwd-re c-awk-neutrals*-re "/"))
+ ;;   Matches a piece of AWK buffer ending in <kwd> /, where <kwd> is a keyword
+ ;; which can precede an expression.
  
  ;; REGEXPS USED FOR FINDING THE POSITION OF A "virtual semicolon"
  (defconst c-awk-_-harmless-nonws-char-re "[^#/\"\\\\\n\r \t]")
***************
*** 721,729 ****
      (goto-char anchor)
      ;; Analyze the line to find out what the / is.
      (if (if anchor-state-/div
!             (not (search-forward-regexp c-awk-regexp-sign-re (1+ /point) t))
!           (search-forward-regexp c-awk-div-sign-re (1+ /point) t))
!         ;; A division sign.
  	(progn (goto-char (1+ /point)) nil)
        ;; A regexp opener
        ;; Jump over the regexp innards, setting the match data.
--- 738,747 ----
      (goto-char anchor)
      ;; Analyze the line to find out what the / is.
      (if (if anchor-state-/div
! 	    (not (search-forward-regexp c-awk-regexp-sign-re (1+ /point) t))
! 	  (and (not (search-forward-regexp c-awk-kwd-regexp-sign-re (1+ /point) t))
! 	       (search-forward-regexp c-awk-div-sign-re (1+ /point) t)))
! 	;; A division sign.
  	(progn (goto-char (1+ /point)) nil)
        ;; A regexp opener
        ;; Jump over the regexp innards, setting the match data.
***************
*** 776,787 ****
               (< (point) lim))
        (setq anchor (point))
        (search-forward-regexp c-awk-harmless-string*-here-re nil t)
!       ;; We are now looking at either a " or a /.
!       ;; Do our thing on the string, regexp or division sign.
        (setq anchor-state-/div
!             (if (looking-at "_?\"")
!                 (c-awk-syntax-tablify-string)
!               (c-awk-syntax-tablify-/ anchor anchor-state-/div))))
      nil))
  
  ;; ACM, 2002/07/21: Thoughts: We need an AWK Mode after-change function to set
--- 794,813 ----
               (< (point) lim))
        (setq anchor (point))
        (search-forward-regexp c-awk-harmless-string*-here-re nil t)
!       ;; We are now looking at either a " or a / or a brace/paren/semicolon.
!       ;; Do our thing on the string, regexp or divsion sign or update our state.
        (setq anchor-state-/div
! 	    (cond
! 	     ((looking-at "_?\"")
! 	      (c-awk-syntax-tablify-string))
! 	     ((eq (char-after) ?/)
! 	      (c-awk-syntax-tablify-/ anchor anchor-state-/div))
! 	     ((memq (char-after) '(?{ ?} ?\( ?\;))
! 	      (forward-char)
! 	      nil)
! 	     (t 			; ?\)
! 	      (forward-char)
! 	      t))))
      nil))
  
  ;; ACM, 2002/07/21: Thoughts: We need an AWK Mode after-change function to set


> Leo

-- 
Alan Mackenzie (Nuremberg, Germany).

Message #35 received at 13541 <at> debbugs.gnu.org (full text, mbox):

From: Leo Liu <sdl.web <at> gmail.com>
To: Alan Mackenzie <acm <at> muc.de>
Cc: 13541 <at> debbugs.gnu.org
Subject: Re: bug#13541: 24.2.92; awk-mode: wrong font locking regexp literals
Date: Mon, 28 Jan 2013 09:12:01 +0800

On 2013-01-28 02:59 +0800, Alan Mackenzie wrote:
> Yes, thanks for spotting this.  The situation was more complicated than I
> thought.  I think this replacement patch fixes that case (together with a
> few others).  Would you try it out again, please.

Still fails with:

/a/ { (print /abc/) }

or

/a/ { p /abc/ } # incorrect awk so not sure a bug or feature

Leo

Message #38 received at 13541 <at> debbugs.gnu.org (full text, mbox):

From: Alan Mackenzie <acm <at> muc.de>
To: Leo Liu <sdl.web <at> gmail.com>
Cc: 13541 <at> debbugs.gnu.org
Subject: Re: bug#13541: 24.2.92; awk-mode: wrong font locking regexp literals
Date: Mon, 28 Jan 2013 11:14:17 +0000

Hi, Leo.

On Mon, Jan 28, 2013 at 09:12:01AM +0800, Leo Liu wrote:
> On 2013-01-28 02:59 +0800, Alan Mackenzie wrote:
> > Yes, thanks for spotting this.  The situation was more complicated than I
> > thought.  I think this replacement patch fixes that case (together with a
> > few others).  Would you try it out again, please.

> Still fails with:

> /a/ { (print /abc/) }

Whoops!  There's a slight glitch in one of the regexps in cc-awk.el.  If
there were a space before "print", it would be "all right".  I've sent a
corrected patch below.

> or

> /a/ { p /abc/ } # incorrect awk so not sure a bug or feature

That "/abc/" is two division signs with a variable between them.  :-)
Compare your text with this:

BEGIN { a = 1 }
/a/ { print a /a/ a }

At the moment, after an alphanumeric token, /regexp/ is only a regexp
when the token is one of the keywords ("print" "case" "return").  There
might be more such keywords (I've not found any).  In a way, "printf"
could be one too, except its first argument is always the format string,
so that wouldn't be useful.

Here's the amended patch:



=== modified file 'lisp/progmodes/cc-awk.el'
*** lisp/progmodes/cc-awk.el	2013-01-01 09:11:05 +0000
--- lisp/progmodes/cc-awk.el	2013-01-28 10:57:52 +0000
***************
*** 127,148 ****
  ;; escaped EOL.
  
  ;; REGEXPS FOR "HARMLESS" STRINGS/LINES.
- (defconst c-awk-harmless-char-re "[^_#/\"\\\\\n\r]")
- ;;   Matches any character but a _, #, /, ", \, or newline.  N.B. _" starts a
- ;; localization string in gawk 3.1
  (defconst c-awk-harmless-_ "_\\([^\"]\\|\\'\\)")
  ;;   Matches an underline NOT followed by ".
  (defconst c-awk-harmless-string*-re
    (concat "\\(" c-awk-harmless-char-re "\\|" c-awk-esc-pair-re "\\|" c-awk-harmless-_ "\\)*"))
! ;;   Matches a (possibly empty) sequence of chars without unescaped /, ", \,
! ;; #, or newlines.
  (defconst c-awk-harmless-string*-here-re
    (concat "\\=" c-awk-harmless-string*-re))
! ;; Matches the (possibly empty) sequence of chars without unescaped /, ", \,
! ;; at point.
  (defconst c-awk-harmless-line-re
!   (concat c-awk-harmless-string*-re
!           "\\(" c-awk-comment-without-nl "\\)?" c-awk-nl-or-eob))
  ;;   Matches (the tail of) an AWK \"logical\" line not containing an unescaped
  ;; " or /.  "logical" means "possibly containing escaped newlines".  A comment
  ;; is matched as part of the line even if it contains a " or a /.  The End of
--- 127,155 ----
  ;; escaped EOL.
  
  ;; REGEXPS FOR "HARMLESS" STRINGS/LINES.
  (defconst c-awk-harmless-_ "_\\([^\"]\\|\\'\\)")
  ;;   Matches an underline NOT followed by ".
+ (defconst c-awk-harmless-char-re "[^_#/\"{}();\\\\\n\r]")
+ ;;   Mathches any character not significant in the state machine applying
+ ;; syntax-table properties to "s and /s.
  (defconst c-awk-harmless-string*-re
    (concat "\\(" c-awk-harmless-char-re "\\|" c-awk-esc-pair-re "\\|" c-awk-harmless-_ "\\)*"))
! ;;   Matches a (possibly empty) sequence of characters insignificant in the
! ;; state machine applying syntax-table properties to "s and /s.
  (defconst c-awk-harmless-string*-here-re
    (concat "\\=" c-awk-harmless-string*-re))
! ;; Matches the (possibly empty) sequence of "insignificant" chars at point.
! 
! (defconst c-awk-harmless-line-char-re "[^_#/\"\\\\\n\r]")
! ;;   Matches any character but a _, #, /, ", \, or newline.  N.B. _" starts a
! ;; localisation string in gawk 3.1
! (defconst c-awk-harmless-line-string*-re
!   (concat "\\(" c-awk-harmless-line-char-re "\\|" c-awk-esc-pair-re "\\|" c-awk-harmless-_ "\\)*"))
! ;;   Matches a (possibly empty) sequence of chars without unescaped /, ", \,
! ;; #, or newlines.
  (defconst c-awk-harmless-line-re
!   (concat c-awk-harmless-line-string*-re
! 	  "\\(" c-awk-comment-without-nl "\\)?" c-awk-nl-or-eob))
  ;;   Matches (the tail of) an AWK \"logical\" line not containing an unescaped
  ;; " or /.  "logical" means "possibly containing escaped newlines".  A comment
  ;; is matched as part of the line even if it contains a " or a /.  The End of
***************
*** 211,217 ****
  ;; division sign.
  (defconst c-awk-neutral-re
  ;  "\\([{}@` \t]\\|\\+\\+\\|--\\|\\\\.\\)+") ; changed, 2003/6/7
!   "\\([{}@` \t]\\|\\+\\+\\|--\\|\\\\.\\)")
  ;;   A "neutral" char(pair).  Doesn't change the "state" of a subsequent /.
  ;; This is space/tab, braces, an auto-increment/decrement operator or an
  ;; escaped character.  Or one of the (invalid) characters @ or `.  But NOT an
--- 218,224 ----
  ;; division sign.
  (defconst c-awk-neutral-re
  ;  "\\([{}@` \t]\\|\\+\\+\\|--\\|\\\\.\\)+") ; changed, 2003/6/7
!   "\\([}@` \t]\\|\\+\\+\\|--\\|\\\\\\(.\\|[\n\r]\\)\\)")
  ;;   A "neutral" char(pair).  Doesn't change the "state" of a subsequent /.
  ;; This is space/tab, braces, an auto-increment/decrement operator or an
  ;; escaped character.  Or one of the (invalid) characters @ or `.  But NOT an
***************
*** 231,238 ****
  ;; will only work when there won't be a preceding " or / before the sought /
  ;; to foul things up.
  (defconst c-awk-non-arith-op-bra-re
!   "[[\(&=:!><,?;'~|]")
! ;;   Matches an opening BRAcket, round or square, or any operator character
  ;; apart from +,-,/,*,%.  For the purpose at hand (detecting a / which is a
  ;; regexp bracket) these arith ops are unnecessary and a pain, because of "++"
  ;; and "--".
--- 238,245 ----
  ;; will only work when there won't be a preceding " or / before the sought /
  ;; to foul things up.
  (defconst c-awk-non-arith-op-bra-re
!   "[[\({&=:!><,?;'~|]")
! ;;   Matches an openeing BRAcket ,round or square, or any operator character
  ;; apart from +,-,/,*,%.  For the purpose at hand (detecting a / which is a
  ;; regexp bracket) these arith ops are unnecessary and a pain, because of "++"
  ;; and "--".
***************
*** 242,247 ****
--- 249,264 ----
  ;; bracket, in a context where an immediate / would be a division sign.  This
  ;; will only work when there won't be a preceding " or / before the sought /
  ;; to foul things up.
+ (defconst c-awk-pre-exp-alphanum-kwd-re
+   (concat "\\(^\\|\\=\\|[^_\n\r]\\)\\<"
+ 	  (regexp-opt '("print" "return" "case") t)
+ 	  "\\>\\([^_\n\r]\\|$\\)"))
+ ;;   Matches all AWK keywords which can precede expressions (including
+ ;; /regexp/).
+ (defconst c-awk-kwd-regexp-sign-re
+   (concat c-awk-pre-exp-alphanum-kwd-re c-awk-neutrals*-re "/"))
+ ;;   Matches a piece of AWK buffer ending in <kwd> /, where <kwd> is a keyword
+ ;; which can precede an expression.
  
  ;; REGEXPS USED FOR FINDING THE POSITION OF A "virtual semicolon"
  (defconst c-awk-_-harmless-nonws-char-re "[^#/\"\\\\\n\r \t]")
***************
*** 721,729 ****
      (goto-char anchor)
      ;; Analyze the line to find out what the / is.
      (if (if anchor-state-/div
!             (not (search-forward-regexp c-awk-regexp-sign-re (1+ /point) t))
!           (search-forward-regexp c-awk-div-sign-re (1+ /point) t))
!         ;; A division sign.
  	(progn (goto-char (1+ /point)) nil)
        ;; A regexp opener
        ;; Jump over the regexp innards, setting the match data.
--- 738,747 ----
      (goto-char anchor)
      ;; Analyze the line to find out what the / is.
      (if (if anchor-state-/div
! 	    (not (search-forward-regexp c-awk-regexp-sign-re (1+ /point) t))
! 	  (and (not (search-forward-regexp c-awk-kwd-regexp-sign-re (1+ /point) t))
! 	       (search-forward-regexp c-awk-div-sign-re (1+ /point) t)))
! 	;; A division sign.
  	(progn (goto-char (1+ /point)) nil)
        ;; A regexp opener
        ;; Jump over the regexp innards, setting the match data.
***************
*** 776,787 ****
               (< (point) lim))
        (setq anchor (point))
        (search-forward-regexp c-awk-harmless-string*-here-re nil t)
!       ;; We are now looking at either a " or a /.
!       ;; Do our thing on the string, regexp or division sign.
        (setq anchor-state-/div
!             (if (looking-at "_?\"")
!                 (c-awk-syntax-tablify-string)
!               (c-awk-syntax-tablify-/ anchor anchor-state-/div))))
      nil))
  
  ;; ACM, 2002/07/21: Thoughts: We need an AWK Mode after-change function to set
--- 794,813 ----
               (< (point) lim))
        (setq anchor (point))
        (search-forward-regexp c-awk-harmless-string*-here-re nil t)
!       ;; We are now looking at either a " or a / or a brace/paren/semicolon.
!       ;; Do our thing on the string, regexp or divsion sign or update our state.
        (setq anchor-state-/div
! 	    (cond
! 	     ((looking-at "_?\"")
! 	      (c-awk-syntax-tablify-string))
! 	     ((eq (char-after) ?/)
! 	      (c-awk-syntax-tablify-/ anchor anchor-state-/div))
! 	     ((memq (char-after) '(?{ ?} ?\( ?\;))
! 	      (forward-char)
! 	      nil)
! 	     (t 			; ?\)
! 	      (forward-char)
! 	      t))))
      nil))
  
  ;; ACM, 2002/07/21: Thoughts: We need an AWK Mode after-change function to set



> Leo

-- 
Alan Mackenzie (Nuremberg, Germany).

Message #41 received at 13541 <at> debbugs.gnu.org (full text, mbox):

From: Leo Liu <sdl.web <at> gmail.com>
To: Alan Mackenzie <acm <at> muc.de>
Cc: 13541 <at> debbugs.gnu.org
Subject: Re: bug#13541: 24.2.92; awk-mode: wrong font locking regexp literals
Date: Mon, 28 Jan 2013 20:11:08 +0800

On 2013-01-28 19:14 +0800, Alan Mackenzie wrote:
> Whoops!  There's a slight glitch in one of the regexps in cc-awk.el.  If
> there were a space before "print", it would be "all right".  I've sent a
> corrected patch below.

OK, I have no further complaints ;)

Leo

Message #46 received at 13541-done <at> debbugs.gnu.org (full text, mbox):

From: Alan Mackenzie <acm <at> muc.de>
To: 13541-done <at> debbugs.gnu.org
Subject: bug#13541: 24.2.92; awk-mode: wrong font locking regexp literals
Date: Tue, 29 Jan 2013 20:58:52 +0000

Bug fixed.

-- 
Alan Mackenzie (Nuremberg, Germany).

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