bug#59684: 29.0.50; [PATCH] package.el: Insert news for installed packages only

[Philip Kaludercic <philipk@posteo.net>]

Andrii Kolomoiets <andreyk.mad@gmail.com> writes:

> Hi,
>
> In some folder, e.g. "/tmp":
> 1. Create folder named "news"
> 2. emacs -Q
> 3. M-x list-packages
> 4. RET on any available not installed package
>
> This will produce "Read error: Is a directory, /tmp/news" message.
>
> In GNU Emacs 29.0.50
> Repository revision: 2772ebe3667f28cefd0d6134204ce6a3c7a8c323
> Repository branch: master
>
> Adding news to package description was introuced in
> dd98fedd0c7f27bfba046d761042c19181cb461d
>
> Adding Philip to Cc as the author of the original commit.
>
> Attached patch solves issue by checking that:
> 1. pkg-dir is not nil
> 2. pkg-dir is not 'builtin
> 3. "news" is a regular file

This sounds good.

> From 9bd185609643ec861b02b4327295bb6db3b82974 Mon Sep 17 00:00:00 2001
> From: muffinmad <andreyk.mad@gmail.com>
> Date: Mon, 28 Nov 2022 23:09:59 +0200
> Subject: [PATCH] Insert news for installed packages only
>
> * lisp/emacs-lisp/package.el (describe-package-1): Check package is
> installed and "news" is a regular file.
> ---
>  lisp/emacs-lisp/package.el | 6 ++++--
>  1 file changed, 4 insertions(+), 2 deletions(-)
>
> diff --git a/lisp/emacs-lisp/package.el b/lisp/emacs-lisp/package.el
> index 8d44fae30a0..f722eb8fae9 100644
> --- a/lisp/emacs-lisp/package.el
> +++ b/lisp/emacs-lisp/package.el
> @@ -2696,8 +2696,10 @@ describe-package-1
>           (signed (if desc (package-desc-signed desc)))
>           (maintainer (cdr (assoc :maintainer extras)))
>           (authors (cdr (assoc :authors extras)))
> -         (news (and-let* ((file (expand-file-name "news" pkg-dir))
> -                          ((file-readable-p file)))
> +         (news (and-let* (pkg-dir
> +                          ((not built-in))
> +                          (file (expand-file-name "news" pkg-dir))
> +                          ((file-regular-p file)))

Shouldn't we keep `file-readable-p'?

>                   file)))
>      (when (string= status "avail-obso")
>        (setq status "available obsolete"))