bug#66246: ERC buffer is no longer visible

bug#66246: ERC buffer is no longer visible

[BTD Master via Bug reports for GNU Emacs, the Swiss army knife of text editors]

When I login through M-x erc (have also tried erc-tls with the same
results), the erc buffer is no longer visible. Emacs instead remains on
the previous buffer (in my case *scratch*). This did not happen in
previous versions.

I'm able to open the buffer when prompted when exiting emacs, but I am
not able to use it during the prompt state from C-x C-c.

Version: Arch Linux Emacs 29.1-4

Thanks.

bug#66246: ERC buffer is no longer visible

[Corwin Brust]

On Wed, Sep 27, 2023 at 3:35 PM BTD Master via Bug reports for GNU
Emacs, the Swiss army knife of text editors <bug-gnu-emacs@gnu.org>
wrote:
>
> When I login through M-x erc (have also tried erc-tls with the same
> results), the erc buffer is no longer visible. Emacs instead remains on
> the previous buffer (in my case *scratch*). This did not happen in
> previous versions.
>
> I'm able to open the buffer when prompted when exiting emacs, but I am
> not able to use it during the prompt state from C-x C-c.
>
> Version: Arch Linux Emacs 29.1-4
>
> Thanks.

Hi.  The on-join window handling behaviors saw some changes in 29.1
(ERC 5.5) and more are in progress for Emacs 30 (ERC 5.6-git on GNU
ELPA devel).  IIUC, this was motivated because "rolling buffers though
the active window" was seen as being a potential security hazard.

Please look at ERC NEWS file (M-x erc-news RET) and also the variable
'erc-interactive-display' which you almost certainly want to set up in
your Emacs configuration, going forward.  Once you review those let us
know if that clears things up or if you suspect there may be a bug
here.   If you do believe there's a bug it may be helpful to have the
full output produced by M-x report-emacs-bug  (ideally from a session
where you've minimally reproduced the problem, so starting from -Q or
such).

Corwin

bug#66246: ERC buffer is no longer visible

[J.P.]

Hi BTD Master,

Corwin Brust <corwin@bru.st> writes:

> On Wed, Sep 27, 2023 at 3:35 PM BTD Master via Bug reports for GNU
> Emacs, the Swiss army knife of text editors <bug-gnu-emacs@gnu.org>
> wrote:
>>
>> When I login through M-x erc (have also tried erc-tls with the same
>> results), the erc buffer is no longer visible. Emacs instead remains on
>> the previous buffer (in my case *scratch*). This did not happen in
>> previous versions.
>>
>> I'm able to open the buffer when prompted when exiting emacs, but I am
>> not able to use it during the prompt state from C-x C-c.
>>
>> Version: Arch Linux Emacs 29.1-4
>>
>> Thanks.
>
> Hi.  The on-join window handling behaviors saw some changes in 29.1
> (ERC 5.5) and more are in progress for Emacs 30 (ERC 5.6-git on GNU
> ELPA devel).  IIUC, this was motivated because "rolling buffers though
> the active window" was seen as being a potential security hazard.
>
> Please look at ERC NEWS file (M-x erc-news RET) and also the variable
> 'erc-interactive-display' which you almost certainly want to set up in
> your Emacs configuration, going forward.  Once you review those let us
> know if that clears things up or if you suspect there may be a bug
> here.   If you do believe there's a bug it may be helpful to have the
> full output produced by M-x report-emacs-bug  (ideally from a session
> where you've minimally reproduced the problem, so starting from -Q or
> such).

As Corwin helpfully explained, what you're seeing is intentional
(believe it or not) [1]. Just to be clear, you can get the old default
back by doing

  (setopt erc-join-buffer 'buffer)

or

  M-x customize-group RET erc-buffers RET
  C-s erc join buffer RET
  toggling the arrow for item Erc Join Buffer
  and choosing "4 = Use current buffer" from the "Value Menu"
  and then doing C-x C-s or similar to commit the new value

Of course, if you're feeling aggrieved by this development, please make
a case for an alternative [2]. But before that, please consider trying
the new behavior on master [3]. (The option mentioned by Corwin,
`erc-interactive-display', is new in ERC 5.6).

Thanks,
J.P.

P.S. In addition to `report-emacs-bug', you can also try M-x erc-bug
RET, which adds the header "X-Debbugs-CC: emacs-erc@gnu.org" to your
initial email (so we get a copy on ERC's own mailing list) [4].

[1] https://git.savannah.gnu.org/cgit/emacs.git/tree/etc/ERC-NEWS?id=d813f71f#n444
    https://git.savannah.gnu.org/cgit/emacs.git/tree/etc/ERC-NEWS?id=d813f71f#n48
[2] https://lists.gnu.org/archive/html/emacs-erc/2023-06/msg00006.html
[3] https://emacs-erc.gitlab.io/bugs/archive/doc/erc.html#Upgrading
[4] https://lists.gnu.org/mailman/listinfo/emacs-erc

bug#66246: ERC buffer is no longer visible

[J.P.]

BTD Master <btdmaster@disroot.org> writes:

> Hi,
>
> I appreciate the clarification, and I think input stealing is at best
> rude and a worst a security risk, this is true. But I have gone from
> confused to aggrieved.
>
> Also, I guess Arch does not package erc-news? It does not exist. [No
> match] (It's not an issue, I don't mind)

If you mean the command `erc-news', it only exists on master. It does
expect to find an existing etc/ERC-NEWS, but you can optionally download
and display the version from emacs.git by invoking it with C-u.

> If there is still a chance to change this behaviour,

If you mean in Emacs 29, I'd say probably not. We also can't patch ERC
5.5 because GNU ELPA only allows :core packages to track master, which
is already at 5.6.

> may I recommend
> either:
> 1. erc-not-interactive as a command for programmatic use, and revert to
> the previous behavior (my preferred option) OR
> 2. erc-interactive as a command for interactive use, and tell users
> that still use erc or erc-tls or similar that they might want to
> use that
>
> Of course, if neither suggestion is good, I'll get used to the extra
> line in the configuration file, but I might bet a few GNU Bucks that I
> won't be the last filing this pseudo-bug.
>
> All the best, no hard feelings,
> b

I guess you weren't able to try the version on HEAD (ERC 5.6-git). Some
of what you propose is more or less present in the new behavior.

Thanks and closing.