bug#47679: 28.0.50; python-shell-switch-to-shell redisplay bug

bug#47679: 28.0.50; python-shell-switch-to-shell redisplay bug

[Shitikanth Kashyap]

Steps to reproduce:
1. emacs -Q
2. Open any python file
3. Press "C-c C-p"  to start interpreter
4. Press "C-c C-z" from the file's window to switch to interpreter
5. Go back to file's window with "C-x o" and repeat from 4 a few times.

There is notable lag (sometimes as much as a few seconds) between
pressing the keybinding "C-c C-z" in file's window before the cursor
appears to be ready on the interpreter's window. The state of the cursor
in the two windows after the command appears to be indeterministic and
inconsistent.

The issue seems to be that the display of the two windows is not updated
even though internally emacs has changed the focus to the correct
window. For example, it is possible to start typing in the interpreter
window immediately after the command, even though the cursor does not
seem to ready.

bug#47679: 28.0.50; python-shell-switch-to-shell redisplay bug

[Shitikanth]

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Proposed fix.

On Sat, 10 Apr 2021 at 02:22, Shitikanth Kashyap <shitikanth1@gmail.com>
wrote:

> Steps to reproduce:
> 1. emacs -Q
> 2. Open any python file
> 3. Press "C-c C-p"  to start interpreter
> 4. Press "C-c C-z" from the file's window to switch to interpreter
> 5. Go back to file's window with "C-x o" and repeat from 4 a few times.
>
> There is notable lag (sometimes as much as a few seconds) between
> pressing the keybinding "C-c C-z" in file's window before the cursor
> appears to be ready on the interpreter's window. The state of the cursor
> in the two windows after the command appears to be indeterministic and
> inconsistent.
>
> The issue seems to be that the display of the two windows is not updated
> even though internally emacs has changed the focus to the correct
> window. For example, it is possible to start typing in the interpreter
> window immediately after the command, even though the cursor does not
> seem to ready.
>
>
>
>
>
>

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From b2633cb4bc7b259839f1ac3a6215e839c2a74be7 Mon Sep 17 00:00:00 2001
From: Shitikanth Kashyap <shitikanth1@gmail.com>
Date: Sat, 10 Apr 2021 01:32:51 +0530
Subject: [PATCH] Fix python-shell-switch-to-shell redisplay bug

---
 lisp/progmodes/python.el | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/lisp/progmodes/python.el b/lisp/progmodes/python.el
index e5c15d148f..3af0bdde2e 100644
--- a/lisp/progmodes/python.el
+++ b/lisp/progmodes/python.el
@@ -3385,7 +3385,7 @@ python-shell-switch-to-shell
 t when called interactively."
   (interactive "p")
   (pop-to-buffer
-   (process-buffer (python-shell-get-process-or-error msg)) nil t))
+   (process-buffer (python-shell-get-process-or-error msg)) nil 'mark-for-redisplay))
 
 (defun python-shell-send-setup-code ()
   "Send all setup code for shell.
-- 
2.30.2

bug#47679: 28.0.50; python-shell-switch-to-shell redisplay bug

[Lars Ingebrigtsen]

Shitikanth <shitikanth1@gmail.com> writes:

> Proposed fix.

Makes sense to me.

This change was small enough to apply without assigning copyright to the
FSF, but for future patches you want to submit, it might make sense to
get the paperwork started now, so that subsequent patches can be applied
speedily. Would you be willing to sign such paperwork?

-- 
(domestic pets only, the antidote for overdose, milk.)
   bloggy blog: http://lars.ingebrigtsen.no

bug#47679: 28.0.50; python-shell-switch-to-shell redisplay bug

[Shitikanth]

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Gladly. How should I start?

On Mon, 12 Apr 2021 at 14:14, Lars Ingebrigtsen <larsi@gnus.org> wrote:

> Shitikanth <shitikanth1@gmail.com> writes:
>
> > Proposed fix.
>
> Makes sense to me.
>
> This change was small enough to apply without assigning copyright to the
> FSF, but for future patches you want to submit, it might make sense to
> get the paperwork started now, so that subsequent patches can be applied
> speedily. Would you be willing to sign such paperwork?
>
> --
> (domestic pets only, the antidote for overdose, milk.)
>    bloggy blog: http://lars.ingebrigtsen.no
>

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bug#47679: 28.0.50; python-shell-switch-to-shell redisplay bug

[Lars Ingebrigtsen]

Shitikanth <shitikanth1@gmail.com> writes:

> Gladly. How should I start?

Here's the form to get started:


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