Re: gnus-article-view-part no longer seems to work (since commit 041b3904?)

[Stefan Monnier]

>> longer behaves as it used to.  In particular, invoking
>> gnus-article-view-part (typically by hitting "b" but I've tried the
>> other bindings just in case) in the summary buffer does not change the
>> view of the article as it used to (for articles that had, say, text and
>> HTML parts).
>
> This comes from this patch:
>
> commit e1e9e4eefa41bacb6b412e57a569440a0847e4fa
> Author:     Stefan Monnier <monnier@iro.umontreal.ca>
> AuthorDate: Fri Jan 29 23:58:58 2021 -0500
>
>     * lisp/gnus/gnus-art.el: Add `event` args and operate at its position.
>
> In particular, it's this bit:
>
> (defun gnus-article-press-button (&optional event)
>   "Check text at point for a callback function.
> If the text at point has a `gnus-callback' property,
> call it with the value of the `gnus-data' text property."
>   (interactive (list last-nonmenu-event))
>   (save-excursion
>     (mouse-set-point event)
>
> `mouse-set-point' here changes the buffer to the summary buffer.  I'm
> not quite sure what the rationale here is...  and there's no mouse
> involved...
>
> Stefan?

Hmm... indeed in the OP's case the function is not called interactively,
but via some other function (`gnus-article-view-part`) which
changes buffer.  We could change the caller to provide some dummy
`event` but it's easier to just replace the 

    (mouse-set-point event)

with

    (if event (mouse-set-point event))


-- Stefan