bug#35055: 27.0.50; async-shell-command truncates output lines

[Michael Albinus]

Juri Linkov <juri@linkov.net> writes:

Hi Juri,

[sorry for the late reply; it was a busy week]

>> Again, using tramp-remote-process-environment seems to be the
>> appropriate place.
>
> Thanks for the suggestion, I customized it to '("COLUMNS=222")
> that is approximately equal to my frame's width, thus `ps`
> shows enough output, and `dpkg -l '*emacs*'` is not too wide
> ('dpkg' tries to fill all available columns).
>
> Should a similar option be added for async-shell-command as well?
>
> diff --git a/lisp/simple.el b/lisp/simple.el
> index 857e0fc001..7212686add 100644
> --- a/lisp/simple.el
> +++ b/lisp/simple.el
> @@ -3336,6 +3336,15 @@ async-shell-command-display-buffer
>    :group 'shell
>    :version "26.1")
>
> +(defcustom async-shell-command-width nil
> +  "Number of columns available for shell command.
> +If nil, use the shell default number (usually 80).
> +If a positive integer, use a fixed width."
> +  :type '(choice (const :tag "Use system limit" nil)
> +                 (integer :tag "Fixed width" :value 80))
> +  :group 'shell
> +  :version "27.1")
> +
>  (defcustom shell-command-dont-erase-buffer nil
>    "If non-nil, output buffer is not erased between shell commands.
>  Also, a non-nil value sets the point in the output buffer
> @@ -3599,8 +3608,13 @@ shell-command
>               (with-current-buffer buffer
>                    (shell-command--save-pos-or-erase)
>                 (setq default-directory directory)
> -                  (setq proc
> -                        (start-process-shell-command "Shell" buffer command))
> +               (let ((process-environment
> +                      (if (natnump async-shell-command-width)
> +                          (cons (format "COLUMNS=%d" 
> async-shell-command-width)
> +                                process-environment)
> +                        process-environment)))
> +                 (setq proc
> +                       (start-process-shell-command "Shell" buffer command)))
>                 (setq mode-line-process '(":%s"))
>                 (require 'shell) (shell-mode)
>                    (set-process-sentinel proc #'shell-command-sentinel)

What about calling this just `shell-command-width'? It wouldn't hurt for
synchronous shell commands, and I could adapt
`tramp-remote-process-environment' accordingly if set. Might be more
convenient for users.

Best regards, Michael.