bug#57884: [PATCH] Flymake backend using the shellcheck program

[Eli Zaretskii <eliz@gnu.org>]

> From: Augusto Stoffel <arstoffel@gmail.com>
> Date: Sat, 17 Sep 2022 18:48:19 +0200
> 
> See https://www.shellcheck.net/ for details on the ShellCheck program.
> It seems to be the most usual linter for shell scripts.

Thanks.

> * lisp/progmodes/sh-script.el (sh-shellcheck-program,
> sh--shellcheck-process, sh-shellcheck-flymake): Variables and function
> defining a Flymake backend.
> (sh-mode): Add it to 'flymake-diagnostic-functions'.

Please mention the bug number in the log message.

> +(defcustom sh-shellcheck-command '("shellcheck")
> +  "The shellcheck program followed by extra arguments."
> +  :type 'string)

This lacks the :version tag.

Also, wouldn't it be better to have separate user options for the
program and the switches?  That way, there won't be a need to require
users to provide a list as the value of the option.

> +(defun sh-shellcheck-flymake (report-fn &rest _args)
> +  "Flymake backend using the shellcheck program.

The first line of a function's doc string should mention its
arguments.

And I think this warrants a NEWS entry.