.emacs.d/init.d/basics/package-management.el

;;; package-management.el --- Initialize package management -*- lexical-binding: t; -*-

;; Time-stamp: <2020-11-18T18:09:44+0100>

;;; Commentary:
;; * Set up straight
;; * Set up use-package.

;;; Code:

;; Workaround for < 26.3 <https://debbugs.gnu.org/cgi/bugreport.cgi?bug=34341>.
(when (and (< emacs-major-version 27)
           (not (string= emacs-version "26.3")))
  (defvar gnutls-algorithm-priority "NORMAL:-VERS-TLS1.3"))

;; Define variables for straight.
(customize-set-variable
 'straight-use-package-by-default t
 "Makes use-package invoke straight.el to install the package.")
(customize-set-variable 'straight-cache-autoloads t
                        "Cache the autoloads of all packages in a single file.")

;; Use shallow clones if available disk space is under 5 GiB.
(when (or (< emacs-major-version 27)    ; file-system-info was introduced in 27.
          (< (nth 2 (file-system-info user-emacs-directory))
             (* 1024 1024 1024 5))) ; 5 GiB.
  (customize-set-variable 'straight-vc-git-default-clone-depth 1
                          "Make shallow clones to save space."))

(customize-set-variable 'straight-repository-branch "master")
;; Bootstrap straight.
(defvar bootstrap-version)
(let ((bootstrap-file
       (expand-file-name "straight/repos/straight.el/bootstrap.el"
                         user-emacs-directory))
      (bootstrap-version 5))
  (unless (file-exists-p bootstrap-file)
    (with-current-buffer
        (url-retrieve-synchronously
         "https://raw.githubusercontent.com/raxod502/straight.el/develop/install.el"
         'silent 'inhibit-cookies)
      (goto-char (point-max))
      (eval-print-last-sexp)))
  (load bootstrap-file nil 'nomessage))
(require 'straight)

;; Isolate package configurations.
(straight-use-package 'use-package)
(customize-set-variable 'use-package-always-defer t)
(require 'use-package)

(use-package straight
  :config (progn
            (defun my/straight-update-repos ()
              "Update recipe repositories."
              (interactive)
              (dolist (package straight-recipe-repositories)
                (straight-pull-package package)))

            (defun my/straight-check-last-update ()
              "Update recipe repositories after 7 days have passed since the last package was built."
              (let ((days 7)
                    (mtime-seconds (time-to-seconds
                                    (file-attribute-modification-time
                                     (file-attributes (straight--build-dir))))))
                (when (> (- (time-to-seconds) mtime-seconds)
                         (* 60 60 24 days))
                  (my/straight-update-repos)))))
  :hook ((emacs-startup . my/straight-check-last-update)
         ((after-init . straight-prune-build))))

(provide 'basics/package-management)
;;; package-management.el ends here