bug#16111: (erc-current-logfile buf) behavior differs to with-current-buffer buf

bug#16111: (erc-current-logfile buf) behavior differs to with-current-buffer buf

[Ivan Shmakov]

Package:  emacs
Severity: minor

	My guess is that the results of (erc-current-logfile buffer) and
	(with-current-buffer buffer (erc-current-logfile)) were intended
	to be the same.  However, as the function references the session
	buffer-local variables (erc-session-server, erc-session-port,
	and, indirectly, erc-server-current-nick and erc-server-process)
	/without/ switching to the buffer given, the results are
	somewhat undefined.

(defun erc-current-logfile (&optional buffer)
  "Return the logfile to use for BUFFER.
If BUFFER is nil, the value of `current-buffer' is used.
This is determined by `erc-generate-log-file-name-function'.
The result is converted to lowercase, as IRC is case-insensitive"
  (unless buffer (setq buffer (current-buffer)))
  (let ((target (or (buffer-name buffer) (erc-default-target)))
	(nick (erc-current-nick))
	(server erc-session-server)
	(port erc-session-port))
    …))

	(There, it may make sense to enclose the most part of the code
	within a with-current-buffer form.)

	This may show no symptoms as long as erc-save-buffer-in-logs is
	called in either of the buffers belonging to the same session,
	but I’m in doubt that erc-log-save-all-buffers (which may run as
	part of kill-emacs-hook) will behave sensible in general.

-- 
FSF associate member #7257

bug#16111: (erc-current-logfile buf) behavior differs to with-current-buffer buf

[Lars Ingebrigtsen]

Ivan Shmakov <ivan@siamics.net> writes:

> Package:  emacs
> Severity: minor
>
> 	My guess is that the results of (erc-current-logfile buffer) and
> 	(with-current-buffer buffer (erc-current-logfile)) were intended
> 	to be the same.  However, as the function references the session
> 	buffer-local variables (erc-session-server, erc-session-port,
> 	and, indirectly, erc-server-current-nick and erc-server-process)
> 	/without/ switching to the buffer given, the results are
> 	somewhat undefined.
>
> (defun erc-current-logfile (&optional buffer)
>   "Return the logfile to use for BUFFER.
> If BUFFER is nil, the value of `current-buffer' is used.
> This is determined by `erc-generate-log-file-name-function'.
> The result is converted to lowercase, as IRC is case-insensitive"
>   (unless buffer (setq buffer (current-buffer)))
>   (let ((target (or (buffer-name buffer) (erc-default-target)))
> 	(nick (erc-current-nick))
> 	(server erc-session-server)
> 	(port erc-session-port))
>     …))
>
> 	(There, it may make sense to enclose the most part of the code
> 	within a with-current-buffer form.)

Do you have a patch for this?

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

bug#16111: (erc-current-logfile buf) behavior differs to with-current-buffer buf

[Lars Ingebrigtsen]

Ivan Shmakov <ivan@siamics.net> writes:

> 	(There, it may make sense to enclose the most part of the code
> 	within a with-current-buffer form.)

I've now done this in Emacs 27.1.

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