Re: [RFC PATCH] gnus: Add piem-gnus-mid-to-thread

[yoctocell <public@yoctocell.xyz>]

On Mon, Jan 18 2021, Kyle Meyer wrote:

>> ---
>> The function works as expected when running
>> 'M-: (funcall (piem-gnus-mid-thread t))', but when running
>> piem-b4-am-from-mid interactively, it just inserts an empty string.
>>
>> Any ideas of why this happens?  Sorry, my elisp skills are not that great.
>
> Yes, I think you just need to move the lambda deeper so that the
> messages are collected outside of the returned function.

Ok, I will see if this works.

>> diff --git a/piem-gnus.el b/piem-gnus.el
>> index 5f10be8..f91f91c 100644
>> --- a/piem-gnus.el
>> +++ b/piem-gnus.el
>> @@ -58,6 +58,30 @@
>>  ;; If there is an easy way to generate an mbox for a thread in Gnus, a
>>  ;; function for `piem-mid-to-thread-functions' should be defined.
>>  
>> +(defun piem-gnus-mid-to-thread (_mid)
>
> Hmm, yeah, I don't think we can convince Gnus to do much useful with the
> message ID here.  However, perhaps there should at least be a check that
> the given message ID matches the one for the article at point before
> returning a function (i.e. claiming piem-gnus-mid-to-thread can generate
> a thread for the given MID).
>
> Also, I think this would need to be guarded by
>
>   (derived-mode-p 'gnus-summary-mode)

Yeah, that's a good idea.  `gnus-summary-refer-parent-article` doesn't
seem to work in article mode.

>> +    (save-excursion
>> +      ;; Cursor has to be at the root of the thread
>> +      (gnus-summary-refer-parent-article most-positive-fixnum)
>> +      (let ((articles (gnus-summary-articles-in-thread))
>> +	    message
>> +	    ;; Just show raw message
>> +	    (gnus-have-all-headers t)
>> +	    gnus-article-prepare-hook
>> +	    gnus-article-decode-hook
>> +	    gnus-display-mime-function
>> +	    gnus-break-pages)
>
> Is the above set of variables (or this approach in general) based off of
> an example from the Gnus source code?

Yeah, I had to do quite a bit of digging to figure this out.  You can
find them in the definition of `gnus-summary-show-article`.

>> +	(mapc (lambda (article)
>> +		(gnus-summary-display-article article)
>> +		(push (format "From mboxrd@z Thu Jan  1 00:00:00 1970\n%s\n"
>> +			      (with-current-buffer gnus-article-buffer
>> +				(buffer-substring-no-properties
>> +				 (point-min)
>> +				 (point-max))))
>> +			      message))
>> +		articles)
>
> For mboxrd, I suppose there needs to be some From-munging.

Sorry, I don't really know much about mbox, I just copied the line from
the mbox file generated by public-inbox :)