core: add guards around package-refresh-contents redefinition

Authorize Spacemacs to redefine the function only for tested versions.

Author: syl20bnr

core/core-emacs-ext.el

@@ -11,39 +11,50 @@
 ;;; License: GPLv3
 (require 'core-spacemacs-buffer)
 
-;; for some reason with-eval-after-load does not work here in 24.3
-;; maybe the backport is incorrect!
-(eval-after-load 'package
-  '(progn
-     (defun package-refresh-contents ()
-       "Download the ELPA archive description if needed.
+;; Disclaimer:
+;; The code in this file is not meant to stay for ever, they are
+;; temporary fixes that we should remove as soon as a better
+;; solution is found.
+
+;; TODO remove this code as soon as we have a clean alternative.
+;; A good proposal is available here:
+;; https://github.com/syl20bnr/spacemacs/commit/4d87ea626dafc066d911c83538e260dd2bef762f#commitcomment-14708731
+(when (and (version<= "24.3.1" emacs-version)
+           (version<= emacs-version "24.5.1"))
+  ;; for some reason with-eval-after-load does not work here in 24.3
+  ;; maybe the backport is incorrect!
+  (eval-after-load 'package
+    '(progn
+       (defun package-refresh-contents ()
+         "Download the ELPA archive description if needed.
  This informs Emacs about the latest versions of all packages, and
  makes them available for download.
 
 This redefinition adds a timeout of 5 seconds to contact each archive."
-       (interactive)
-       ;; the first part is not available before Emacs 24.4 so we just ignore
-       ;; it to be safe.
-       (unless (version< emacs-version "24.4")
-         ;; FIXME: Do it asynchronously.
-         (unless (file-exists-p package-user-dir)
-           (make-directory package-user-dir t))
-         (let ((default-keyring (expand-file-name "package-keyring.gpg"
-                                                  data-directory)))
-           (when (and package-check-signature (file-exists-p default-keyring))
-             (condition-case-unless-debug error
-                 (progn
-                   (epg-check-configuration (epg-configuration))
-                   (package-import-keyring default-keyring))
-               (error (message "Cannot import default keyring: %S" (cdr error)))))))
-       (dolist (archive package-archives)
-         (condition-case-unless-debug nil
-             (with-timeout (5 (spacemacs-buffer/warning
-                               "Cannot contact archive %s (reason: timeout)"
-                               (cdr archive)))
-               (package--download-one-archive archive "archive-contents"))
-           (error (message "Failed to download `%s' archive."
-                           (car archive)))))
-       (package-read-all-archive-contents))))
+         (interactive)
+         ;; the first part is not available before Emacs 24.4 so we just ignore
+         ;; it to be safe.
+         (unless (version< emacs-version "24.4")
+           ;; FIXME: Do it asynchronously.
+           (unless (file-exists-p package-user-dir)
+             (make-directory package-user-dir t))
+           (let ((default-keyring (expand-file-name "package-keyring.gpg"
+                                                    data-directory)))
+             (when (and package-check-signature (file-exists-p default-keyring))
+               (condition-case-unless-debug error
+                   (progn
+                     (epg-check-configuration (epg-configuration))
+                     (package-import-keyring default-keyring))
+                 (error (message "Cannot import default keyring: %S" (cdr error)))))))
+         (dolist (archive package-archives)
+           (condition-case-unless-debug nil
+               ;; add timeout here
+               (with-timeout (5 (spacemacs-buffer/warning
+                                 "Cannot contact archive %s (reason: timeout)"
+                                 (cdr archive)))
+                 (package--download-one-archive archive "archive-contents"))
+             (error (message "Failed to download `%s' archive."
+                             (car archive)))))
+         (package-read-all-archive-contents)))))
 
 (provide 'core-emacs-ext)