bug#46042: 27.1; xref-revert-buffer will delete buffer contents

bug#46042: 27.1; xref-revert-buffer will delete buffer contents

[Vangelis Evangelou]

Hello. In a scratch buffer containing some text, run the function
xref-revert-buffer. The buffer content will be deleted and it is not
possible to undo. The function should check that it is applied in a
suitable buffer before modifying the buffer.


In GNU Emacs 27.1 (build 1, x86_64-pc-linux-gnu, X toolkit, Xaw3d scroll 
bars)
  of 2020-08-11 built on ThinkPad-T410
Windowing system distributor 'The X.Org Foundation', version 11.0.12009000
System Description: Linux Mint 20.1

Recent messages:
For information about GNU Emacs and the GNU system, type C-h C-a.
Loading xref...done
xref-revert-buffer: Symbol’s function definition is void: nil
primitive-undo: Changes to be undone are outside visible portion of buffer

Configured using:
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Memory information:
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bug#46042: 27.1; xref-revert-buffer will delete buffer contents

[Dmitry Gutov]

Version: 28.1

Hi!

On 22.01.2021 21:12, Vangelis Evangelou wrote:
> 
> Hello. In a scratch buffer containing some text, run the function
> xref-revert-buffer. The buffer content will be deleted and it is not
> possible to undo. The function should check that it is applied in a
> suitable buffer before modifying the buffer.

Thanks for the report. Indeed, it sounds unfortunate, if you just called 
the command accidentally.

I've pushed a fix (which will make it complain with (void-function nil) 
instead of erasing the buffer) to master. Sometime later, we'll tag a 
new release of the xref package, and you'll be able to update to the new 
version through 'M-x list-packages'.

bug#46042: 27.1; xref-revert-buffer will delete buffer contents

[Eli Zaretskii]

> From: Dmitry Gutov <dgutov@yandex.ru>
> Date: Sat, 23 Jan 2021 02:59:39 +0200
> 
> I've pushed a fix (which will make it complain with (void-function nil) 
> instead of erasing the buffer) to master.

Should this be backported to the emacs-27 branch?

bug#46042: 27.1; xref-revert-buffer will delete buffer contents

[Dmitry Gutov]

On 23.01.2021 10:03, Eli Zaretskii wrote:
>> From: Dmitry Gutov<dgutov@yandex.ru>
>> Date: Sat, 23 Jan 2021 02:59:39 +0200
>>
>> I've pushed a fix (which will make it complain with (void-function nil)
>> instead of erasing the buffer) to master.
> Should this be backported to the emacs-27 branch?

Why not.

Backported, thanks.

bug#46042: 27.1; xref-revert-buffer will delete buffer contents

[Dmitry Gutov]

Hi Eli,

I've just fixed a minor bug in the new implementation (e86b30d6fd).

Can I backport that to emacs-27 now?

bug#46042: 27.1; xref-revert-buffer will delete buffer contents

[Eli Zaretskii]

> From: Dmitry Gutov <dgutov@yandex.ru>
> Cc: evangelou@gmail.com, 46042@debbugs.gnu.org
> Date: Fri, 29 Jan 2021 15:54:35 +0200
> 
> Hi Eli,
> 
> I've just fixed a minor bug in the new implementation (e86b30d6fd).
> 
> Can I backport that to emacs-27 now?

Yes.  But emacs-27.1.91 is already out...

bug#46042: 27.1; xref-revert-buffer will delete buffer contents

[Dmitry Gutov]

On 29.01.2021 16:01, Eli Zaretskii wrote:
> Yes.  But emacs-27.1.91 is already out...

Yeah, just saw that. Nothing I can do about that, I suppose.

But the fix is now on the release branch.