bug#23571: 25.1.50; Click-mouse-1 = Drag-mouse-1 in Gnus Article buffer

[Stephen Berman <stephen.berman@gmx.net>]

On Tue, 07 Jun 2016 05:31:34 +0300 Eli Zaretskii <eliz@gnu.org> wrote:

>> From: Stephen Berman <stephen.berman@gmx.net>
>> Cc: 23571@debbugs.gnu.org
>> Date: Mon, 06 Jun 2016 21:38:02 +0200
>> 
>> >> 72166f2f3dba18f1217c666574032f5a0351ed65 is the first bad commit
>> >> commit 72166f2f3dba18f1217c666574032f5a0351ed65
>> >> Author: Martin Rudalics <rudalics@gmx.at>
>> >> Date:   Tue May 3 08:38:49 2016 +0200
>> >> 
>> >>     Bind `widget-button-click' to mouse-1/-2 instead of down-mouse-1/-2
>> >>     
>> >>     * lisp/wid-edit.el (widget-keymap): Bind `widget-button-click'
>> >>     to mouse-1/-2 instead of down-mouse-1/-2.  Suggested by Stefan
>> >>     Monnier.  (Bug#19185, Bug#20398)
>> >
>> > So I guess Gnus needs to do something to countermand the low-level
>> > change, right?
>> 
>> It turns out it's not just Gnus Article buffers (as presciently
>> suggested by the title of bug#23653, which I merged with this one): in
>> fact, the same problem appears to happen in all packages in which
>> buffers use widget-keymap; there are quite a few of these, as rgrepping
>> for widget-keymap on the lisp directory shows, and in all that I tried
>> (cus-edit, wid-browse, recentf, printing, secrets, image-dired,
>> todo-mode) the problem with mouse-1 occurred.  So I think the fix should
>> be in widget-button-click, or somewhere at that level, and not in all of
>> its users.
>
> How do you do that without reintroducing the bug referenced in the
> above commit's log message?

I went through those two bug reports and I cannot reproduce the
problematic cases (bug#19185: mouse-2 running mouse-yank-primary in a
Gnus Article buffer; bug#20398: mouse-1 raising error "No selection is
available" on links in a Customize buffer) with -Q in current emacs-25,
which does not include the above commit.  And when I revert that commit
in master I also cannot reproduce those problems.  So it's not clear to
me what that commit is trying to fix.

Steve Berman