bug#9841: 23.3; rmail-edit-current-message adds extra '>'s to Froms...

bug#9841: 23.3; rmail-edit-current-message adds extra '>'s to Froms...

[Mark Lillibridge]

Start with a Rmail message (this one will do) not containing MIME that
contains lines like the following:

>From level 1
>>From level 2
>>>From level 3

Hit 'e' to edit the message.  Notice that nothing changes.  Now hit ^c^c
or ^c^] to stop editing (the later is supposed to abort, leaving the
message unchanged).  Notice that your message now has one more > in
front of each of the from lines:

>>From level 1
>>>From level 2
>>>>From level 3

You can repeat this as many times as you like, adding more and more >'s.


Towards a patch, I notice that rmail-cease-edit has the following code:

rmailedit.el:135:
  ;; Disguise any "From " lines so they don't start a new message.
  (goto-char (point-min))
  (or rmail-old-pruned (forward-line 1))
  (while (re-search-forward "^>*From " nil t)
    (beginning-of-line)
    (insert ">")
    (forward-line))

There is no corresponding code in the rmail-edit-current-message or the
viewing code that I can find.


    This probably needs more thought, but I think the decode code should
remove one >, and the incorporate new messages and done editting code
should add one > (as above).  Note this is related to bug #6574: Rmail
23 uses a broken mailbox format (mboxo) instead of a sane one like
mboxrd.

    I note that fetchmail to mbox loses information because it only adds
a > to From's without one already.  This is arguably not Rmail's fault,
however.

- Mark

bug#9841: 23.3; rmail-edit-current-message adds extra '>'s to Froms...

[Glenn Morris]

Version: 24.4

Mark Lillibridge wrote:

> Start with a Rmail message (this one will do) not containing MIME that
> contains lines like the following:

Actually, I can only reproduce this with a message that _is_ MIME, ie
has a "MIME-version: 1.0" header (which almost everything does).
For non-MIME messages, rmail-show-message-1 _does_ add >, which is
why rmail-cease-edit tries to put them back. Anyway, I installed a
change to make it not do that for MIME messages, which have not been
unescaped during display.

bug#9841: closed (Re: bug#9841: 23.3; rmail-edit-current-message adds extra '>'s to Froms...)

[Mark Lillibridge]

Glenn Morris <rgm@gnu.org> wrote:
> Mark Lillibridge wrote:
> 
> > Start with a Rmail message (this one will do) not containing MIME that
> > contains lines like the following:
> 
> Actually, I can only reproduce this with a message that _is_ MIME, ie
> has a "MIME-version: 1.0" header (which almost everything does).
> For non-MIME messages, rmail-show-message-1 _does_ add >, which is
> why rmail-cease-edit tries to put them back. Anyway, I installed a
> change to make it not do that for MIME messages, which have not been
> unescaped during display.

    You're right; this problem does not occur with non-MIME messages
under 24.2 (my current test system).

    I think your patch may not work correctly if the user adds a "From "
line to a MIME message.  Seems like there are two choices: (1) give an
error in that case and refuse to exit editing (similar to the screwed up
headers case) or (2) unescape From lines when the edit starts and
re-escape them when the edit finishes.  (2) seems friendlier to users as
it means users don't have to manually escape From lines when editing.

- Mark