bug#29767: 26.0.90; Failing auto-fill in message-mode because of bad state (comment-skip-end)

[Tomas Nordin <tomasn@posteo.net>]

Jose Antonio Ortega Ruiz <jao@gnu.org> writes:

> not for me. i am answering here with a long line, and the two quoted
> lines above don't trigger the bug on my side.  here you see the lines
> that was auto-filled without any extra >.

I have been experimenting with this, debugging with debugger. An early
function called is do-auto-fill. In the process at some point later, the
function comment-beginning is called to determine if we are in a comment
or not. If it returns nil, there will be no problems, when it returns a
value there will be problems. In that case point is also moved to the
place above the text where the comment syntax is picked (or prefix if
you want).

I have been in reply buffers where there is no problem and then in reply
buffers where there is problem. But also in a buffer where there was
this problem in the bottom of the buffer but not in the mid of the
buffer.

Anyhow, I claim that if you eval (comment-beginning) with point close to
the break point and it returns nil, there will be no problem. Else, a
value is returned and point will move back in the buffer and there will
be problems when filling.

No fix here but just adding in the hope it could be of any use.

Regards
--
Tomas