vcursor.el: `vcursor-copy-word` and `vcursory-copy-line` not working as expected

vcursor.el: `vcursor-copy-word` and `vcursory-copy-line` not working as expected

[Narendra Joshi]

Hi,

I think `vcursor.el` has a bug that causes `point` (the real cursor) to
move to where the virtual cursor is whenever `vcursor-copy-{word,line}`
are used. 

We need to wrap the `goto-char` call below in something like
`save-excursion`:

--8<---------------cut here---------------start------------->8---
1 file changed, 3 insertions(+), 4 deletions(-)
lisp/vcursor.el | 7 +++----

modified   lisp/vcursor.el
@@ -785,12 +785,11 @@ vcursor-get-char-count
 
 This is called by most of the virtual-cursor copying commands to find
 out how much to copy."
-
   (vcursor-check)
   (with-current-buffer (overlay-buffer vcursor-overlay)
-    (let ((start (goto-char (overlay-start vcursor-overlay))))
-      (- (progn (apply func args) (point)) start)))
-  )
+    (save-excursion
+      (let ((start (goto-char (overlay-start vcursor-overlay))))
+        (- (progn (apply func args) (point)) start)))))
 
 ;; Make sure the virtual cursor is active.  Unless arg is non-nil,
 ;; report an error if it is not.
--8<---------------cut here---------------end--------------->8---

Best regards,
-- 
Narendra Joshi

Re: vcursor.el: `vcursor-copy-word` and `vcursory-copy-line` not working as expected

[Eli Zaretskii]

> From: Narendra Joshi <narendraj9@gmail.com>
> Date: Tue, 23 Nov 2021 20:30:55 +0100
> 
> I think `vcursor.el` has a bug that causes `point` (the real cursor) to
> move to where the virtual cursor is whenever `vcursor-copy-{word,line}`
> are used. 
> 
> We need to wrap the `goto-char` call below in something like
> `save-excursion`:

Thanks, but I think save-excursion should be deeper, immediately befor
we call goto-char.  It is not good practice to change buffers inside
save-excursion.

Re: vcursor.el: `vcursor-copy-word` and `vcursory-copy-line` not working as expected

[Narendra Joshi]

Sounds good to me, please move the `save-excursion` call nearer to
`goto-char` if/when you have the time. Thank you for the explanation :) 

Best regards,
-- 
Narendra Joshi

Re: vcursor.el: `vcursor-copy-word` and `vcursory-copy-line` not working as expected

[Stefan Monnier]

> I think `vcursor.el` has a bug that causes `point` (the real cursor) to
> move to where the virtual cursor is whenever `vcursor-copy-{word,line}`
> are used. 
>
> We need to wrap the `goto-char` call below in something like
> `save-excursion`:


Thanks, pushed to `master`.


        Stefan

Re: vcursor.el: `vcursor-copy-word` and `vcursory-copy-line` not working as expected

[Narendra Joshi]

[-- Attachment #1: Type: text/plain, Size: 412 bytes --]

Great, thanks :)

On Wed, 24 Nov 2021, 17:58 Stefan Monnier, <monnier@iro.umontreal.ca> wrote:

> > I think `vcursor.el` has a bug that causes `point` (the real cursor) to
> > move to where the virtual cursor is whenever `vcursor-copy-{word,line}`
> > are used.
> >
> > We need to wrap the `goto-char` call below in something like
> > `save-excursion`:
>
>
> Thanks, pushed to `master`.
>
>
>         Stefan
>
>

[-- Attachment #2: Type: text/html, Size: 743 bytes --]