From mboxrd@z Thu Jan  1 00:00:00 1970
From: Nicolas Goaziou <mail@nicolasgoaziou.fr>
Subject: Re: [PATCH] org-id-goto doesn't work if buffer is narrowed.
Date: Sun, 25 Oct 2015 10:42:37 +0100
Message-ID: <877fmbb7xu.fsf@nicolasgoaziou.fr>
References: <CALnw1fRTyShwsk0_G0VMDzfC+6YCCiNxveua36y982LJFfeVNg@mail.gmail.com>
	<874mhh1u7s.fsf@gmx.us>
	<CALnw1fSycwXL-hBfm=x0ejrvSHGZVr6mxm2aV-+=Q4VFUXDkXg@mail.gmail.com>
	<87oafpz65e.fsf@gmx.us>
	<CALnw1fRk0a0SpfDASVz8G66iHH4sHGm24WnhkoW69ycBjrVnpQ@mail.gmail.com>
	<87pp04zc1r.fsf@gmx.us>
	<CALnw1fQc63_3yxiwwCywP4tSfHBdPBh9i9b2-u5g6ca=0E+U1w@mail.gmail.com>
	<CALnw1fRd-NMBW7VTVFTzP6io4qApU3Am1g=LdReJf_zxi1UaDg@mail.gmail.com>
	<87k2qbbaw3.fsf@nicolasgoaziou.fr>
	<CALnw1fR6G=cHgT+Rk52XRHU-T=oZm+vyihyjLZU_bp0sqh5zeA@mail.gmail.com>
Mime-Version: 1.0
Content-Type: text/plain
Return-path: <emacs-orgmode-bounces+geo-emacs-orgmode=m.gmane.org@gnu.org>
Received: from eggs.gnu.org ([2001:4830:134:3::10]:33295)
	by lists.gnu.org with esmtp (Exim 4.71)
	(envelope-from <mail@nicolasgoaziou.fr>) id 1ZqHnK-00062g-Jx
	for emacs-orgmode@gnu.org; Sun, 25 Oct 2015 05:40:55 -0400
Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71)
	(envelope-from <mail@nicolasgoaziou.fr>) id 1ZqHnJ-0003ob-Iz
	for emacs-orgmode@gnu.org; Sun, 25 Oct 2015 05:40:54 -0400
Received: from relay3-d.mail.gandi.net ([2001:4b98:c:538::195]:45910)
	by eggs.gnu.org with esmtp (Exim 4.71)
	(envelope-from <mail@nicolasgoaziou.fr>) id 1ZqHnJ-0003oX-Ck
	for emacs-orgmode@gnu.org; Sun, 25 Oct 2015 05:40:53 -0400
In-Reply-To: <CALnw1fR6G=cHgT+Rk52XRHU-T=oZm+vyihyjLZU_bp0sqh5zeA@mail.gmail.com>
	(Puneeth Chaganti's message of "Sun, 25 Oct 2015 14:40:23 +0530")
List-Id: "General discussions about Org-mode." <emacs-orgmode.gnu.org>
List-Unsubscribe: <https://lists.gnu.org/mailman/options/emacs-orgmode>,
	<mailto:emacs-orgmode-request@gnu.org?subject=unsubscribe>
List-Archive: <http://lists.gnu.org/archive/html/emacs-orgmode>
List-Post: <mailto:emacs-orgmode@gnu.org>
List-Help: <mailto:emacs-orgmode-request@gnu.org?subject=help>
List-Subscribe: <https://lists.gnu.org/mailman/listinfo/emacs-orgmode>,
	<mailto:emacs-orgmode-request@gnu.org?subject=subscribe>
Errors-To: emacs-orgmode-bounces+geo-emacs-orgmode=m.gmane.org@gnu.org
Sender: emacs-orgmode-bounces+geo-emacs-orgmode=m.gmane.org@gnu.org
To: Puneeth Chaganti <punchagan@gmail.com>
Cc: emacs-orgmode <emacs-orgmode@gnu.org>, Rasmus <rasmus@gmx.us>

Puneeth Chaganti <punchagan@gmail.com> writes:

> Thanks for your careful review and detailed comments.  I've attached
> an updated patch.

Thank you. I have another suggestion about it.

> +(defun org-id-show (id cmd)
> +  "Show an entry with id ID by buffer-switching using CMD.
> +CMD is a function that takes a buffer or a string (buffer name)
> +as an argument, which will be used to switch to the buffer
> +containing the entry with id ID."
> +  (let ((m (org-id-find id 'marker)))
> +    (unless m
> +      (error "Cannot find entry with ID \"%s\"" id))
> +    (unless (equal (current-buffer) (marker-buffer m))
> +      (funcall cmd (marker-buffer m)))

Nitpick: (eq (current-buffer) (marker-buffer m))
  
> +    (when (let ((pos (marker-position m)))
> +	    (or (< pos (point-min))
> +		(> pos (point-max))))
> +      (widen))
> +    (goto-char m)
> +    (move-marker m nil)
> +    (org-show-context 'link-search)))

If CMD raises an error, you have a dangling marker in the buffer, which
is not a great idea. I suggest to wrap everything into
a `unwind-protect' and add (set-marker m nil) as an unwindform, i.e.,

  (let ((m (org-id-find id 'marker)))
    (unless m (error "Cannot find entry with ID \"%s\"" id))
    (unwind-protect
        (progn
          (unless (eq (current-buffer) (marker-buffer m))
            (funcall cmd (marker-buffer m)))
          (when (let ((pos (marker-position m)))
                  (or (< pos (point-min))
                      (> pos (point-max))))
            (widen))
          (goto-char m)
          (org-show-context 'link-search))
      (set-marker m nil)))

Regards,