bug#65129: 30.0.50; pinch gestures suddenly stops being recognised

[Visuwesh]

[Tuesday August 08, 2023] Po Lu wrote:

> No worries there, please instrument handle_one_xevent like so:
>
> diff --git a/src/xterm.c b/src/xterm.c
> index f454733c659..57b06c571f6 100644
> --- a/src/xterm.c
> +++ b/src/xterm.c
> @@ -24722,6 +24722,11 @@ handle_one_xevent (struct x_display_info *dpyinfo,
>             x_display_set_last_user_time (dpyinfo, pev->time,
>                                           pev->send_event, true);
>  
> +           if (device)
> +             fprintf (stderr, "XI_GesturePinchBegin: %d\n", device->use);
> +           else
> +             fprintf (stderr, "XI_GesturePinchBegin: no device\n");
> +
>             if (!device || device->use != XIMasterPointer)
>               goto XI_OTHER;
>  
> and show us what is printed when you attempt a pinch gesture after they
> cease being delivered.

I see nothing being printed once pinch gestures stop being recognised.
I see XI_GesturePinchBegin: 1 a whole bunch of times when they still
work though.
I confirmed that it is printed once again by opening a new frame and
trying the gesture there once it ceased recognised in the original
frame.

P.S., to confirm that I did apply the patch correctly, this is under
"case XI_GesturePinchUpdate:" under handle_one_xevent function right?
When I tried C-c C-a from a diff buffer, I got prompted

    Try to auto-fix whitespace loss? (y or n)

(to which I said yes) so I am not so confident that the patch applied
correctly.