bug#28003: 26.0.50; Auto fill broken in Message mode

[Tom Tromey]

>>>>> "Stephen" == Stephen Berman <stephen.berman@gmx.net> writes:

Stephen> On Wed, 09 Aug 2017 12:33:01 +0900 Katsumi Yamaoka <yamaoka@jpl.org> 
wrote:
>> On Mon, 07 Aug 2017 21:56:42 +0200, Stephen Berman wrote:
>>> This change:
>> [...]
>>> broke auto filling in Message mode; the breakage is due specifically to
>>> this change in comment-indent-new-line:
>> 
>> This will probably be no more than a workaround, though.
>> 
>> --- message.el~      2017-08-08 22:08:28.694840400 +0000
>> +++ message.el       2017-08-09 03:30:33.407170200 +0000
>> @@ -3451,7 +3451,7 @@
>> (defun message-do-auto-fill ()
>> "Like `do-auto-fill', but don't fill in message header."
>> (unless (message-point-in-header-p)
>> -    (do-auto-fill)))
>> +    (let ((comment-start nil)) (do-auto-fill))))
>> 
>> (defun message-insert-signature (&optional force)
>> "Insert a signature.  See documentation for variable `message-signature'."

Stephen> This change doesn't fix the problem.  I don't know what the motivation
Stephen> for the change that caused this problem was, so I don't know how to fix
Stephen> it; cc'ing Tom Tromey, who made the change.

I've been discussing this off-list with another person who ran into this
problem, but I haven't managed to reproduce it myself.

I suspect the newcomment.el change is incorrect and should be reverted.
Could you try that?  The other changes should, I think, remain in place though.

The basic idea of my patch is to make comment-auto-fill-only-comments
work properly.  Without it, setting comment-auto-fill-only-comments and
enabling auto-fill in js-mode will cause auto-filling even when typing a
long line of code, which is clearly incorrect.

thanks,
Tom