Bug#504356: gettext-el: duplicates gettext header with Emacs 23 (fwd)

[Santiago Vila]

Hello.

I received this from the Debian bug system.

---------- Forwarded message ----------
From: address@hidden
To: Debian Bug Tracking System <address@hidden>
Date: Sun, 02 Nov 2008 22:30:40 +0100
Subject: Bug#504356: gettext-el: duplicates gettext header with Emacs 23

Package: gettext-el
Version: 0.17-4
Severity: important

Hello,

at least in Emacs 23, opening a PO file with po-mode unconditionally
adds a new header on top of the file, even if one (or more... the
problem is recursive) header is already present.

This problem does not happen in Emacs 22, that's why I do not set this
as grave, but I believe it deserves "important", because po-mode does
not provide any easy way to remove this duplicate header: once the PO
has been saved, I have to edit it with another editor to fix the mess.

I've tracked down the issue to line 1346 (in po-check-file-header):
(previous-line 1) moves to the end of the previous line, don't ask me
why.

The docstring for previous-line clearly says it should not be used
blindly in a Lisp program:

   If you are thinking of using this in a Lisp program, consider using
   `forward-line' with a negative argument instead.  It is usually easier
   to use and more reliable (no dependence on goal column, etc.).

Replacing this with (forward-line -1) fixes the issue (one-liner patch
attached).

[ ... ]

--- /usr/share/emacs/site-lisp/gettext/po-mode.el       2008-08-27 
19:03:06.000000000 +0200
+++ po-mode.el  2008-11-02 22:15:21.000000000 +0100
@@ -1343,7 +1343,7 @@
             (progn
               ;; There is at least one entry.
               (goto-char (match-beginning 0))
-              (previous-line 1)
+              (forward-line -1)
               (setq end-of-header (match-end 0))
               (if (looking-at "msgid \"\"\n")
                   ;; There is indeed a PO file header.