bug#15826: 24.3.50; SMIE hangs in sh-mode

bug#15826: 24.3.50; SMIE hangs in sh-mode

[Aaron Ecay]

I observe hangs when using sh-mode in recent trunk emacs (latest commit
Tue Nov 5 18:36:37 2013 +0200).  Recipe to reproduce:

- emacs -Q
- C-x C-f foo.sh
- type “for i in”
- immediately after entering the ‘n’, emacs will hang

Setting debug-on-quit to t and quitting yields the following backtrace:
Debugger entered--Lisp error: (quit)
  re-search-backward("\\(?:\\(?:^\\|[^\\]\\)\\(?:\\\\\\\\\\)*\\(\\(?:&&\\|;\\(?:;&\\|[&;]\\)\\||[&|]\\|[&;|]\\)\\)\\)\\=" 1 t)
  looking-back("\\(?:^\\|[^\\]\\)\\(?:\\\\\\\\\\)*\\(\\(?:&&\\|;\\(?:;&\\|[&;]\\)\\||[&|]\\|[&;|]\\)\\)" 1 greedy)
  sh-smie-sh-backward-token()
  sh-smie--sh-keyword-in-p()
  sh-smie--sh-keyword-p("in")
  sh-smie-sh-backward-token()
  smie-blink-matching-open()
  self-insert-command(1)
  call-interactively(self-insert-command nil nil)
  command-execute(self-insert-command)

Thanks,
Aaron



In GNU Emacs 24.3.50.1 (x86_64-unknown-linux-gnu, GTK+ Version 3.10.2)
 of 2013-11-05 on haize
Windowing system distributor `The X.Org Foundation', version 11.0.11404000
Configured using:
 `configure --prefix=/usr --sysconfdir=/etc --localstatedir=/var
 --libexecdir=/usr/lib --mandir=/usr/share/man --without-sound
 --with-xft --with-x-toolkit=gtk --with-gif=no 'CFLAGS=-march=x86-64
 -mtune=generic -O2 -pipe -fstack-protector --param=ssp-buffer-size=4'
 CPPFLAGS=-D_FORTIFY_SOURCE=2
 LDFLAGS=-Wl,-O1,--sort-common,--as-needed,-z,relro'

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

-- 
Aaron Ecay

bug#15826: 24.3.50; SMIE hangs in sh-mode

[Stefan Monnier]

> - emacs -Q
> - C-x C-f foo.sh
> - type “for i in”
> - immediately after entering the ‘n’, emacs will hang

Indeed, thank you.  I installed the patch below which should fix it.


        Stefan


=== modified file 'lisp/progmodes/sh-script.el'
--- lisp/progmodes/sh-script.el	2013-10-24 21:16:20 +0000
+++ lisp/progmodes/sh-script.el	2013-11-08 04:31:52 +0000
@@ -1730,7 +1730,7 @@
 like a keyword, then it is a keyword."
   (let ((prev (funcall smie-backward-token-function)))
     (if (zerop (length prev))
-        (looking-back "\\s(" (1- (point)))
+        (looking-back "\\`\\|\\s(" (1- (point)))
       (assoc prev smie-grammar))))
 
 (defun sh-smie--newline-semi-p (&optional tok)
@@ -1804,12 +1804,14 @@
       (setq prev (funcall smie-backward-token-function))
       (cond
        ((zerop (length prev))
-        (if newline
-            (progn (cl-assert words) (setq res 'word))
+	(cond
+	 (newline (cl-assert words) (setq res 'word))
+	 ((bobp) (setq res 'word))
+	 (t
           (setq words t)
           (condition-case nil
               (forward-sexp -1)
-            (scan-error (setq res 'unknown)))))
+            (scan-error (setq res 'unknown))))))
        ((equal prev ";")
         (if words (setq newline t)
           (setq res 'keyword)))

bug#15826: 24.3.50; SMIE hangs in sh-mode

[Aaron Ecay]

2013ko azaroak 7an, Stefan Monnier-ek idatzi zuen:
>
> Indeed, thank you.  I installed the patch below which should fix it.

It is indeed fixed.  BTW, the (new?) highlighting of for/done, if/fi,
etc. in show-paren-mode is very nifty.

Thanks,

--
Aaron Ecay

bug#15826: 24.3.50; SMIE hangs in sh-mode

[Stefan Monnier]

>> Indeed, thank you.  I installed the patch below which should fix it.
> It is indeed fixed.  BTW, the (new?) highlighting of for/done, if/fi,
> etc. in show-paren-mode is very nifty.

Thanks, I'm glad you like it,


        Stefan