bug#21530: 25.0.50; tty menus disappearing

bug#21530: 25.0.50; tty menus disappearing

[Mark Oteiza]

I didn't see mention of this in the other tty menu reports, so hopefully
not a dupe. From emacs -nw -Q:

1. M-x display-time-mode
2. F10

Wait for the modeline to update. The tty menu will disappear or
otherwise appear broken. It's still there though, running through the
arrow keys will redraw the tty menu.

The same goes for buffers being displayed that redraw themselves
periodically. display-time-mode and display-battery-mode just happen to
be built in.

bug#21530: 25.0.50; tty menus disappearing

[Eli Zaretskii]

> From: Mark Oteiza <mvoteiza@udel.edu>
> Date: Mon, 21 Sep 2015 13:45:39 -0400
> 
> 
> I didn't see mention of this in the other tty menu reports, so hopefully
> not a dupe. From emacs -nw -Q:
> 
> 1. M-x display-time-mode
> 2. F10
> 
> Wait for the modeline to update. The tty menu will disappear or
> otherwise appear broken. It's still there though, running through the
> arrow keys will redraw the tty menu.

On the systems to which I have access (which include GNU/Linux and
MS-Windows), the mode line does not update as long as the menu is
open.  It only gets updated when I exit the menu, e.g., with C-g.
Needless to say, the menu does not disappear nor appears broken.

What terminal emulator do you use?  Do you see some of the problems
described in bug#17497?

> The same goes for buffers being displayed that redraw themselves
> periodically.

Can you show a recipe for this starting from "emacs -Q"?

Thanks.

bug#21530: 25.0.50; tty menus disappearing

[Eli Zaretskii]

> Date: Mon, 21 Sep 2015 22:44:28 +0300
> From: Eli Zaretskii <eliz@gnu.org>
> Cc: 21530@debbugs.gnu.org
> 
> > From: Mark Oteiza <mvoteiza@udel.edu>
> > Date: Mon, 21 Sep 2015 13:45:39 -0400
> > 
> > 
> > I didn't see mention of this in the other tty menu reports, so hopefully
> > not a dupe. From emacs -nw -Q:
> > 
> > 1. M-x display-time-mode
> > 2. F10
> > 
> > Wait for the modeline to update. The tty menu will disappear or
> > otherwise appear broken. It's still there though, running through the
> > arrow keys will redraw the tty menu.
> 
> On the systems to which I have access (which include GNU/Linux and
> MS-Windows), the mode line does not update as long as the menu is
> open.

Moreover, the C function display_mode_lines, which is responsible for
redrawing the mode line of the selected window, does not get called on
my systems for as long as the menu is active.

Can you set a breakpoint in that function, and see if it gets called
while the menu is open?  If it does, please show the backtrace for
those calls, including the Lisp backtrace (a.k.a. "xbacktrace").

Thanks.

bug#21530: 25.0.50; tty menus disappearing

[Mark Oteiza]

Eli Zaretskii <eliz@gnu.org> writes:

>> From: Mark Oteiza <mvoteiza@udel.edu>
>> Date: Mon, 21 Sep 2015 13:45:39 -0400
>> 
>> 
>> I didn't see mention of this in the other tty menu reports, so hopefully
>> not a dupe. From emacs -nw -Q:
>> 
>> 1. M-x display-time-mode
>> 2. F10
>> 
>> Wait for the modeline to update. The tty menu will disappear or
>> otherwise appear broken. It's still there though, running through the
>> arrow keys will redraw the tty menu.
>
> On the systems to which I have access (which include GNU/Linux and
> MS-Windows), the mode line does not update as long as the menu is
> open.  It only gets updated when I exit the menu, e.g., with C-g.
> Needless to say, the menu does not disappear nor appears broken.

I think I gave an incomplete recipe, because I can't reproduce from it
either. I forgot to mention enabling also display-battery-mode, but that
of course requires having a battery or fooling the mode into thinking
you do.

> What terminal emulator do you use?  Do you see some of the problems
> described in bug#17497?

Normally I use a VTE-based terminal emulator called termite, but I'm
able to reproduce in xterm.

As for the bug#17497 things: absolutely. I don't think those problems
have ever gone away.  It gets even worse when resizing the term and
further using the open menu. I haven't read the entire thread for that
bug yet though.

>> The same goes for buffers being displayed that redraw themselves
>> periodically.
>
> Can you show a recipe for this starting from "emacs -Q"?

I'm not aware of a built-in mode that does this, so I'll have to concoct
something.

bug#21530: 25.0.50; tty menus disappearing

[Eli Zaretskii]

> From: Mark Oteiza <mvoteiza@udel.edu>
> Date: Thu, 24 Sep 2015 12:24:46 -0400
> 
> >> The same goes for buffers being displayed that redraw themselves
> >> periodically.
> >
> > Can you show a recipe for this starting from "emacs -Q"?
> 
> I'm not aware of a built-in mode that does this, so I'll have to concoct
> something.

It would be also interesting to see if display_mode_lines gets called
when the menu is active, and see the backtrace for that.

bug#21530: 25.0.50; tty menus disappearing

[Eli Zaretskii]

> From: Mark Oteiza <mvoteiza@udel.edu>
> Date: Thu, 24 Sep 2015 12:24:46 -0400
> 
> I think I gave an incomplete recipe, because I can't reproduce from it
> either. I forgot to mention enabling also display-battery-mode, but that
> of course requires having a battery or fooling the mode into thinking
> you do.

No, you don't have to have a battery to invoke display-battery-mode.

Thanks, with this I can reproduce the problem here.  It looks like the
problem is that display-battery-mode forces redisplay by calling
sit-for (display-time-mode wisely doesn't).

bug#21530: 25.0.50; tty menus disappearing

[Mark Oteiza]

Eli Zaretskii <eliz@gnu.org> writes:

>> From: Mark Oteiza <mvoteiza@udel.edu>
>> Date: Thu, 24 Sep 2015 12:24:46 -0400
>> 
>> I think I gave an incomplete recipe, because I can't reproduce from it
>> either. I forgot to mention enabling also display-battery-mode, but that
>> of course requires having a battery or fooling the mode into thinking
>> you do.
>
> No, you don't have to have a battery to invoke display-battery-mode.
>
> Thanks, with this I can reproduce the problem here.  It looks like the
> problem is that display-battery-mode forces redisplay by calling
> sit-for (display-time-mode wisely doesn't).

Okay, good. I see that now. I was having trouble for a while figuring
out how to get the backtrace

Lisp Backtrace:
"redisplay_internal (C function)" (0x0)
"redisplay" (0xffffa0d8)
"sit-for" (0xffffa600)
"battery-update-handler" (0xffffac78)
"apply" (0xffffac70)
"timer-event-handler" (0xffffb1b8)
"x-popup-menu" (0xffffc6c0)
"popup-menu" (0xffffcc00)
"menu-bar-open" (0xffffd430)
"funcall-interactively" (0xffffd428)
"call-interactively" (0xffffd580)
"command-execute" (0xffffdac8)

bug#21530: 25.0.50; tty menus disappearing

[Eli Zaretskii]

> From: Mark Oteiza <mvoteiza@udel.edu>
> Date: Thu, 24 Sep 2015 13:48:06 -0400
> 
> > Thanks, with this I can reproduce the problem here.  It looks like the
> > problem is that display-battery-mode forces redisplay by calling
> > sit-for (display-time-mode wisely doesn't).
> 
> Okay, good. I see that now. I was having trouble for a while figuring
> out how to get the backtrace
> 
> Lisp Backtrace:
> "redisplay_internal (C function)" (0x0)
> "redisplay" (0xffffa0d8)
> "sit-for" (0xffffa600)
> "battery-update-handler" (0xffffac78)
> "apply" (0xffffac70)
> "timer-event-handler" (0xffffb1b8)
> "x-popup-menu" (0xffffc6c0)
> "popup-menu" (0xffffcc00)
> "menu-bar-open" (0xffffd430)
> "funcall-interactively" (0xffffd428)
> "call-interactively" (0xffffd580)
> "command-execute" (0xffffdac8)

Right, I see this as well.

Could you please try the current master, and see if the problem is
solved?  I could only test that on MS-Windows (don't have access to a
Posix system with battery status reporting).

bug#21530: 25.0.50; tty menus disappearing

[Mark Oteiza]

On 24/09/15 at 09:11pm, Eli Zaretskii wrote:
> > From: Mark Oteiza <mvoteiza@udel.edu>
> > Date: Thu, 24 Sep 2015 13:48:06 -0400
> > 
> > > Thanks, with this I can reproduce the problem here.  It looks like the
> > > problem is that display-battery-mode forces redisplay by calling
> > > sit-for (display-time-mode wisely doesn't).
> > 
> > Okay, good. I see that now. I was having trouble for a while figuring
> > out how to get the backtrace
> > 
> > Lisp Backtrace:
> > "redisplay_internal (C function)" (0x0)
> > "redisplay" (0xffffa0d8)
> > "sit-for" (0xffffa600)
> > "battery-update-handler" (0xffffac78)
> > "apply" (0xffffac70)
> > "timer-event-handler" (0xffffb1b8)
> > "x-popup-menu" (0xffffc6c0)
> > "popup-menu" (0xffffcc00)
> > "menu-bar-open" (0xffffd430)
> > "funcall-interactively" (0xffffd428)
> > "call-interactively" (0xffffd580)
> > "command-execute" (0xffffdac8)
> 
> Right, I see this as well.
> 
> Could you please try the current master, and see if the problem is
> solved?  I could only test that on MS-Windows (don't have access to a
> Posix system with battery status reporting).

Appears to be fixed. Thank you!

bug#21530: 25.0.50; tty menus disappearing

[Eli Zaretskii]

> Date: Thu, 24 Sep 2015 14:25:08 -0400
> From: Mark Oteiza <mvoteiza@udel.edu>
> Cc: 21530@debbugs.gnu.org
> 
> > Could you please try the current master, and see if the problem is
> > solved?  I could only test that on MS-Windows (don't have access to a
> > Posix system with battery status reporting).
> 
> Appears to be fixed. Thank you!

OK, thanks.  I'm closing the bug; feel free to reopen if you discover
some left-overs or adverse effects.