bug#51757: 27.2; [patch] man.el : wait for all man(1) output to be buffered before fontifying

[Jason Vas Dias]

---------- Forwarded message ----------
From: Jason Vas Dias <jason.vas.dias@gmail.com>
Date: Fri, 12 Nov 2021 15:49:20 +0000
Subject: Re: bug#51757: 27.2; [patch] man.el : wait for all man(1)
output to be buffered before fontifying
To: Juri Linkov <juri@linkov.net>

What version of Emacs / man / groff are you running ?
Mine are:
  $ rpm -q emacs man groff-base
emacs-27.2-5.fc34.x86_64
package man is not installed
groff-base-1.22.4-7.fc34.x86_64

Are you using the Red Hat patches to Emacs ?
If not, it may be an RH patch related thing.
It happens 100% every time loading the bash manpage for
me, at the same places in the file.

Thanks & Best Regards,
Jason

On 11/11/2021, Juri Linkov <juri@linkov.net> wrote:
>>> Of course, with the man.el from emacs-28, I get the error:
>>>   'completing-read: Symbol’s function definition is void: format-prompt'
>>> under Emacs-27.2 , which is NOT Emacs-28 :-( .
>>>
>>> If you can do 'M-x manual-entry bash' in Emacs-28, and
>>> it never misses a font transition, let me know - I will
>>> re-examine once Fedora's Emacs 28 comes out.
>>>
>>> But I enclose a screenshot of how the bash manpage looks with the
>>> Emacs 27.2 man.el, with all the remaining text of the man-page
>>> after the start of the 'PARAMETERS' section in bold, because
>>> only a partial escape sequence was at the end of the buffer
>>> and the transition was missed by fontification-on-the-fly .
>>
>> I just did that, and I see no problems with the font transitions.
>
> Maybe reproducibility depends on the value of 'read-process-output-max'?
> But I tried to set it to a very small value (100), and still no ANSI
> sequence was emitted partially between font-lock iterations.
>