bug#18985: 24.3; cperl-mode misindents hash keys that start with an auto-quoted keyword

bug#18985: 24.3; cperl-mode misindents hash keys that start with an auto-quoted keyword

[Ævar Arnfjörð Bjarmason]

cperl-mode has a nasty bug in M-x indent-region, if you write this to a
file:
    
    my %x = (
        for_me => "cookie",
    );

And indent it you end up with:

    my %x = (
	 for _me => "cookie",
    );

Note the space between the "for" and "_me", the indenter falsely thought
that "for" was a keyword and suffixed it with a space, changing the
semantics of the code.

The same issue happens with some other keywords, e.g. "if" and "until",
but interestingly not "unless".
    
    
In GNU Emacs 24.3.1 (x86_64-pc-linux-gnu)
 of 2014-09-08 on binet, modified by Debian
System Description:	Debian GNU/Linux testing (jessie)

Configured using:
 `configure '--build' 'x86_64-linux-gnu' '--build' 'x86_64-linux-gnu'
 '--prefix=/usr' '--sharedstatedir=/var/lib' '--libexecdir=/usr/lib'
 '--localstatedir=/var/lib' '--infodir=/usr/share/info'
 '--mandir=/usr/share/man' '--with-pop=yes'
 '--enable-locallisppath=/etc/emacs24:/etc/emacs:/usr/local/share/emacs/24.3/site-lisp:/usr/local/share/emacs/site-lisp:/usr/share/emacs/24.3/site-lisp:/usr/share/emacs/site-lisp'
 '--with-crt-dir=/usr/lib/x86_64-linux-gnu' '--with-x=no'
 '--without-gconf' '--without-gsettings' 'build_alias=x86_64-linux-gnu'
 'CFLAGS=-g -O2 -fstack-protector-strong -Wformat
 -Werror=format-security -Wall' 'LDFLAGS=-Wl,-z,relro'
 'CPPFLAGS=-D_FORTIFY_SOURCE=2''

Important settings:
  value of $LANG: en_US.utf8
  locale-coding-system: utf-8-unix
  default enable-multibyte-characters: t

Major mode: CPerl

Minor modes in effect:
  menu-bar-mode: t
  file-name-shadow-mode: t
  global-font-lock-mode: t
  font-lock-mode: t
  auto-composition-mode: t
  auto-encryption-mode: t
  auto-compression-mode: t
  line-number-mode: t
  transient-mark-mode: t

Recent input:
C-@ C-x h C-w i f SPC ( DEL DEL DEL DEL f o r _ m e 
SPC = > SPC " c o o k i e " ; DEL , C-a C-@ C-e ESC 
x i n d e n t - r e g TAB RET ESC x c p e r l - m o 
d e RET C-a C-p RET C-p m y SPC % x SPC = SPC ( C-n 
TAB C-e RET ) TAB ; C-@ C-p C-p C-a ESC x i n d e n 
t - r e g TAB RET C-_ C-@ C-n C-g C-@ C-p C-p C-a ESC 
w C-x b C-g ESC x r e p o r t - e m a TAB RET

Recent messages:
Mark set [3 times]
Mark activated
You can run the command `indent-region' with C-M-\
byte-code: Beginning of buffer
End of `mf ... f' string/RE not found: (scan-error Unbalanced parentheses 3 22)
Mark set
Undo!
Mark set
Quit
Mark set
Quit

Load-path shadows:
None found.

Features:
(shadow sort gnus-util mail-extr emacsbug message format-spec rfc822 mml
mml-sec mm-decode mm-bodies mm-encode mail-parse rfc2231 mailabbrev
gmm-utils mailheader sendmail regexp-opt rfc2047 rfc2045 ietf-drums
mm-util mail-prsvr mail-utils cperl-mode easymenu time-date ediff-hook
vc-hooks lisp-float-type tabulated-list newcomment lisp-mode register
page menu-bar rfn-eshadow timer select mouse jit-lock font-lock syntax
facemenu font-core frame cham georgian utf-8-lang misc-lang vietnamese
tibetan thai tai-viet lao korean japanese hebrew greek romanian slovak
czech european ethiopic indian cyrillic chinese case-table epa-hook
jka-cmpr-hook help simple abbrev minibuffer loaddefs button faces
cus-face macroexp files text-properties overlay sha1 md5 base64 format
env code-pages mule custom widget hashtable-print-readable backquote
make-network-process dbusbind multi-tty emacs)

bug#18985: 24.3; cperl-mode misindents hash keys that start with an auto-quoted keyword

[Stefan Kangas]

avarab@gmail.com (Ævar Arnfjörð Bjarmason) writes:

> cperl-mode has a nasty bug in M-x indent-region, if you write this to a
> file:
>
>     my %x = (
>         for_me => "cookie",
>     );
>
> And indent it you end up with:
>
>     my %x = (
>      for _me => "cookie",
>     );
>
> Note the space between the "for" and "_me", the indenter falsely thought
> that "for" was a keyword and suffixed it with a space, changing the
> semantics of the code.
>
> The same issue happens with some other keywords, e.g. "if" and "until",
> but interestingly not "unless".

I can reproduce this on Emacs 26.2.

Best regards,
Stefan Kangas

bug#18985: [PATCH] Fix indent-region for identifiers with underscores

[Harald Jörg]

[-- Attachment #1: Type: text/plain, Size: 87 bytes --]

Another bug report from 2014 caught my attention.
A patch is attached.
-- 
Cheers,
haj

[-- Attachment #2: 0001-2020-08-27-Harald-J-rg-haj-posteo.de.patch --]
[-- Type: text/x-patch, Size: 2381 bytes --]

From c3b3c7b8a2105d39e81c6f8ccf19a1600659bcce Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Harald=20J=C3=B6rg?= <haj@posteo.de>
Date: Thu, 27 Aug 2020 22:57:53 +0200
Subject: [PATCH] =?UTF-8?q?2020-08-27=20=20Harald=20J=C3=B6rg=20=20<haj@po?=
 =?UTF-8?q?steo.de>?=
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

 * lisp/progmodes/cperl-mode.el (cperl-fix-line-spacing): Fix Bug#18985.
 Hash keys or function names starting with a Perl keyword followed
 by an underscore (as in "for_me" are no longer split into two words
 by M-x indent-region.
---
 lisp/progmodes/cperl-mode.el | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/lisp/progmodes/cperl-mode.el b/lisp/progmodes/cperl-mode.el
index c47aa2ea8c..44579cfd38 100644
--- a/lisp/progmodes/cperl-mode.el
+++ b/lisp/progmodes/cperl-mode.el
@@ -4876,7 +4876,7 @@ cperl-fix-line-spacing
       ;;  }? continue
       ;;  blah; }
       (if (not
-	   (or (looking-at "[ \t]*\\(els\\(e\\|if\\)\\|continue\\|if\\|while\\|for\\(each\\)?\\|until\\)")
+	   (or (looking-at "[ \t]*\\(els\\(e\\|if\\)\\|continue\\|if\\|while\\|for\\(each\\)?\\|unless\\|until\\)\\_>")
 	       (setq have-brace (save-excursion (search-forward "}" ee t)))))
 	  nil				; Do not need to do anything
 	;; Looking at:
@@ -4884,7 +4884,7 @@ cperl-fix-line-spacing
 	;; else
 	(if cperl-merge-trailing-else
 	    (if (looking-at
-		 "[ \t]*}[ \t]*\n[ \t\n]*\\(els\\(e\\|if\\)\\|continue\\)\\>")
+		 "[ \t]*}[ \t]*\n[ \t\n]*\\(els\\(e\\|if\\)\\|continue\\)\\_>")
 		(progn
 		  (search-forward "}")
 		  (setq p (point))
@@ -4892,7 +4892,7 @@ cperl-fix-line-spacing
 		  (delete-region p (point))
 	      (insert (make-string cperl-indent-region-fix-constructs ?\s))
 		  (beginning-of-line)))
-	  (if (looking-at "[ \t]*}[ \t]*\\(els\\(e\\|if\\)\\|continue\\)\\>")
+	  (if (looking-at "[ \t]*}[ \t]*\\(els\\(e\\|if\\)\\|continue\\)\\_>")
 	      (save-excursion
 		  (search-forward "}")
 		  (delete-horizontal-space)
@@ -4904,7 +4904,7 @@ cperl-fix-line-spacing
 			(setq ret (point)))))))
 	;; Looking at:
 	;; }     else
-	(if (looking-at "[ \t]*}\\(\t*\\|[ \t][ \t]+\\)\\<\\(els\\(e\\|if\\)\\|continue\\)\\>")
+	(if (looking-at "[ \t]*}\\(\t*\\|[ \t][ \t]+\\)\\<\\(els\\(e\\|if\\)\\|continue\\)\\_>")
 	    (progn
 	      (search-forward "}")
 	      (delete-horizontal-space)
-- 
2.20.1

bug#18985: [PATCH] Fix indent-region for identifiers with underscores

[Lars Ingebrigtsen]

Harald Jörg <haj@posteo.de> writes:

> Another bug report from 2014 caught my attention.
> A patch is attached.

Thanks; applied to Emacs 28.

-- 
(domestic pets only, the antidote for overdose, milk.)
   bloggy blog: http://lars.ingebrigtsen.no