From 52a49907e53a0f4f484e0759ae317fd728f12153 Mon Sep 17 00:00:00 2001
From: Xiyue Deng <manphiz@gmail.com>
Date: Fri, 20 Jun 2025 21:34:45 -0700
Subject: Add public interfaces for accessing builtin package info (Bug#78844)

The following upstream patch has been backported:

  Add public interfaces for accessing builtin package info (Bug#78844)

  * lisp/emacs-lisp/package.el (package-builtin-packages)
  (package-builtin-package-version): New functions.
  * doc/lispref/package.texi: Add a section 'Package Information' with
  documentation for the new functions.
  * etc/NEWS: Add entry for 'package-versioned-builtin-packages' and
  'package-builtin-package-version'.

Origin: upstream, commit 5c75ec6ae52a5b06ad0424ce805f5ea0432b6e90
Forwarded: not-needed
---
 lisp/emacs-lisp/package.el | 15 +++++++++++++++
 1 file changed, 15 insertions(+)

diff --git a/lisp/emacs-lisp/package.el b/lisp/emacs-lisp/package.el
index be3b85f3179..82b7520a707 100644
--- a/lisp/emacs-lisp/package.el
+++ b/lisp/emacs-lisp/package.el
@@ -669,6 +669,21 @@ package-alist
 loaded and/or activated, customize `package-load-list'.")
 (put 'package-alist 'risky-local-variable t)
 
+;;;; Public interfaces for accessing built-in package info
+
+(defun package-versioned-builtin-packages ()
+  "Return a list of all the versioned built-in packages.
+The return value is a list of names of built-in packages represented as
+symbols."
+  (mapcar #'car package--builtin-versions))
+
+(defun package-builtin-package-version (package)
+  "Return the version of a built-in PACKAGE given by its symbol.
+The return value is a list of integers representing the version of
+PACKAGE, in the format returned by `version-to-list', or nil if the
+package is built-in but has no version or is not a built-in package."
+  (alist-get package package--builtin-versions))
+
 ;;;###autoload
 (defvar package-activated-list nil
   ;; FIXME: This should implicitly include all builtin packages.
