bug#3375: 23.0.94; Document incompatible change to format of bookmarks

bug#3375: 23.0.94; Document incompatible change to format of bookmarks

[Drew Adams]

Emacs 23 apparently introduces an incompatible change to the format of
bookmarks. A bookmark that formerly would have had this form:
("Directories"
  ((front-context-string . "\n22.8 File Direc")
   (rear-context-string . ": > Directories\n")
   (position . 133657)
   (filename . "c:/Emacs-23-0-3/info/emacs")
   (info-node . "Directories")
   (handler . Info-bookmark-jump)))
 
Now can have this form:
("Directories"
  (front-context-string . "\n22.8 File Direc")
  (rear-context-string . ": > Directories\n")
  (position . 133657)
  (filename . "c:/Emacs-23-0-3/info/emacs")
  (info-node . "Directories")
  (handler . Info-bookmark-jump))
 
The is handled in the changed definition of
`bookmark-get-bookmark-record', which accommodates both forms.
However, if you try to do, say, `C-x r l' in Emacs 22 and you have
created a bookmark of the latter form (using Emacs 23), then `C-x r l'
raises an error.  That's normal - Emacs 22 can't know about the
incompatible change that Emacs 23 introduces.
 
I don't know why this change was necessary. (Why?) But let's assume
that it was in fact necessary. The bug is that it is totally
undocumented.
 
Please _at least_ document this in NEWS. The _only_ thing mentioned in
NEWS about bookmarks is this:
 
 "*** bookmark provides `bookmark-make-record-function' so
 special major modes like Info can teach bookmark.el how to save
 and restore the relevant data."
 
 
 
In GNU Emacs 23.0.94.1 (i386-mingw-nt5.1.2600) of 2009-05-24 on
 SOFT-MJASON Windowing system distributor `Microsoft Corp.', version
 5.1.2600 configured using `configure --with-gcc (3.4)'
 

bug#3375: marked as done (23.0.94; Document incompatible change to format of bookmarks)

[Emacs bug Tracking System]

[-- Attachment #1: Type: text/plain, Size: 898 bytes --]

Your message dated Fri, 09 Oct 2009 01:30:30 -0400
with message-id <87ljjlb0cp.fsf@red-bean.com>
and subject line Fix "Document incompatible change to format of bookmarks"
has caused the Emacs bug report #3375,
regarding 23.0.94; Document incompatible change to format of bookmarks
to be marked as done.

This means that you claim that the problem has been dealt with.
If this is not the case it is now your responsibility to reopen the
bug report if necessary, and/or fix the problem forthwith.

(NB: If you are a system administrator and have no idea what this
message is talking about, this may indicate a serious mail system
misconfiguration somewhere. Please contact owner@emacsbugs.donarmstrong.com
immediately.)


-- 
3375: http://emacsbugs.donarmstrong.com/cgi-bin/bugreport.cgi?bug=3375
Emacs Bug Tracking System
Contact owner@emacsbugs.donarmstrong.com with problems

[-- Attachment #2: Type: message/rfc822, Size: 4314 bytes --]

From: "Drew Adams" <drew.adams@oracle.com>
To: <emacs-pretest-bug@gnu.org>
Subject: 23.0.94; Document incompatible change to format of bookmarks
Date: Mon, 25 May 2009 12:50:40 -0700
Message-ID: <CB62005DF20044D194A7CFB95ACF6B54@us.oracle.com>

Emacs 23 apparently introduces an incompatible change to the format of
bookmarks. A bookmark that formerly would have had this form:
("Directories"
  ((front-context-string . "\n22.8 File Direc")
   (rear-context-string . ": > Directories\n")
   (position . 133657)
   (filename . "c:/Emacs-23-0-3/info/emacs")
   (info-node . "Directories")
   (handler . Info-bookmark-jump)))
 
Now can have this form:
("Directories"
  (front-context-string . "\n22.8 File Direc")
  (rear-context-string . ": > Directories\n")
  (position . 133657)
  (filename . "c:/Emacs-23-0-3/info/emacs")
  (info-node . "Directories")
  (handler . Info-bookmark-jump))
 
The is handled in the changed definition of
`bookmark-get-bookmark-record', which accommodates both forms.
However, if you try to do, say, `C-x r l' in Emacs 22 and you have
created a bookmark of the latter form (using Emacs 23), then `C-x r l'
raises an error.  That's normal - Emacs 22 can't know about the
incompatible change that Emacs 23 introduces.
 
I don't know why this change was necessary. (Why?) But let's assume
that it was in fact necessary. The bug is that it is totally
undocumented.
 
Please _at least_ document this in NEWS. The _only_ thing mentioned in
NEWS about bookmarks is this:
 
 "*** bookmark provides `bookmark-make-record-function' so
 special major modes like Info can teach bookmark.el how to save
 and restore the relevant data."
 
 
 
In GNU Emacs 23.0.94.1 (i386-mingw-nt5.1.2600) of 2009-05-24 on
 SOFT-MJASON Windowing system distributor `Microsoft Corp.', version
 5.1.2600 configured using `configure --with-gcc (3.4)'
 



[-- Attachment #3: Type: message/rfc822, Size: 2052 bytes --]

From: Karl Fogel <kfogel@red-bean.com>
To: 3375-close@emacsbugs.donarmstrong.com
Subject: Fix "Document incompatible change to format of bookmarks"
Date: Fri, 09 Oct 2009 01:30:30 -0400
Message-ID: <87ljjlb0cp.fsf@red-bean.com>

fixed
--

Thanks for the report.  I've documented the format change in NEWS;
here's the commit:

  $ cvs ci -F msg etc/NEWS etc/ChangeLog
  /sources/emacs/emacs/etc/NEWS,v  <--  etc/NEWS
  new revision: 1.2100; previous revision: 1.2099
  /sources/emacs/emacs/etc/ChangeLog,v  <--  etc/ChangeLog
  new revision: 1.812; previous revision: 1.811
  Mailing notification to emacs-diffs@gnu.org... sent.
  $ 

(I don't know why the default write-out format was changed, as I didn't
commit rev 1.114 of bookmark.el.  We could investigate and find out, but
it would be of forensic interest only at this point -- the change is
made, and there's a long list of bookmark.el bugs to go.  So I'm not
going to investigate the reasoning behind 1.114 closely; if you happen
to find out, please let me know.)

-Karl

bug#3375: Fix "Document incompatible change to format of bookmarks"

[Drew Adams]

> Thanks for noticing the problem and taking the time to describe it so
> thoroughly; that was a huge help.

Thanks for your help on this. It helps even just to hear that it's normal to be
confused given the current state and the history. ;-) It's not obvious for
someone who tries to read the code and comments to stay convinced that s?he
understands. ;-)

 - Drew