Mode-line indicator for new release

README.md

@@ -22,6 +22,7 @@
     - [OS X](#os-x)
 - [Install](#install)
 - [Update](#update)
+    - [Update notification](#update-notification)
 - [Configuration](#configuration)
     - [Configuration layers](#configuration-layers)
     - [Dotfile (.spacemacs)](#dotfile-spacemacs)
@@ -192,6 +193,20 @@ Spacemacs currently requires manual updates using the following procedure:
 
 3. Restart Emacs to complete the upgrade.
 
+## Update notification
+
+For convenience an indicator is displayed in the mode-line whenever a new
+version of `Spacemacs` is available.
+
+           Symbol                     | Description
+:------------------------------------:|----------------------------------
+![git-new](doc/img/update-green.png)  | less than 3 releases behind
+![git-del](doc/img/update-orange.png) | less than 5 releases behind
+![git-mod](doc/img/update-red.png)    | 5 or more releases behind
+
+**Note:**
+Update of `Spacemacs` by clicking on the indicator will be implemented _soon_.
+
 # Configuration
 
 `Spacemacs` divides its configuration into self-contained units called

core/configuration-layer.el

@@ -588,6 +588,6 @@ deleted safely."
                  (format "[%s packages loaded in %.3fs]\n"
                          (configuration-layer//initialized-packages-count)
                          elapsed)))
-              )))
+              (spacemacs/check-for-new-version spacemacs-version-check-interval))))
 
 (provide 'configuration-layer)

core/spacemacs-mode.el

@@ -4,12 +4,21 @@
 (require 'subr-x nil 'noerror)
 (require 'emacs-backports)
 
-(defconst spacemacs-version "0.43.0"
+(defconst spacemacs-version "0.40.0"
   "Spacemacs version.")
-
 (defconst spacemacs-min-version "24.3"
   "Mininal required version of Emacs.")
 
+(defconst spacemacs-repository "spacemacs"
+  "Name of the Spacemacs remote repository.")
+(defconst spacemacs-repository-owner "syl20bnr"
+  "Name of the Spacemacs remote repository owner.")
+
+(defgroup spacemacs nil
+  "Spacemacs customizations."
+  :group 'starter-kit
+  :prefix 'spacemacs-)
+
 ;; paths
 (defconst spacemacs-core-directory
   (expand-file-name (concat user-emacs-directory "core/"))
@@ -36,6 +45,16 @@
 ;; if you have a dropbox, then ~/Dropbox/emacs is added to load path
 (add-to-list 'load-path (concat user-dropbox-directory "emacs/"))
 
+;; new version variables
+(defvar spacemacs-new-version nil
+  "If non-nil a new Spacemacs version is available.")
+(defvar spacemacs-version-check-timer nil
+  "The current timer for new version check.")
+(defvar spacemacs-version-check-interval "6 hours"
+  "Time between two version checks.")
+(defvar spacemacs-version-check-lighter "[+]"
+  "Text displayed in the mode-line when a new version is available.")
+
 ;; loading progress bar variables
 (defvar spacemacs-title-length 75)
 (defvar spacemacs-loading-counter 0)
@@ -51,11 +70,6 @@
 (defvar spacemacs-loading-dots-chunk-threshold 0)
 (defvar spacemacs-solarized-dark-createdp nil)
 
-(defgroup spacemacs nil
-  "Spacemacs customizations."
-  :group 'starter-kit
-  :prefix 'spacemacs-)
-
 (define-derived-mode spacemacs-mode special-mode "spacemacs-mode"
   "Spacemacs major mode for startup screen."
   :syntax-table nil
@@ -140,6 +154,10 @@
   (setq-default evil-want-fine-undo nil)
   (spacemacs/load-or-install-package 'evil t)
   (spacemacs/load-or-install-package 'evil-leader t)
+  ;; check for new version
+  (if dotspacemacs-mode-line-unicode-symbols
+      (setq-default spacemacs-version-check-lighter "[⬆]"))
+  (spacemacs/set-new-version-lighter-mode-line-faces)
   ;; motion state since this is a special mode
   (add-to-list 'evil-motion-state-modes 'spacemacs-mode))
 
@@ -202,6 +220,93 @@ FILE-TO-LOAD is an explicit file to load after the installation."
   "Change the default welcome message of minibuffer to another one."
   (message "Spacemacs is ready."))
 
+(defun spacemacs//get-last-version (repo owner)
+  "Return the last version fetched from Github REPO of OWNER."
+  (let* ((api (gh-repos-api "api"))
+         (repo (oref (gh-repos-repo-get api spacemacs-repository
+                                        spacemacs-repository-owner) :data))
+         (tags (oref (gh-repos-repo-tags api repo) :data))
+         (last-version (cdr (assq 'name (nth 0 tags)))))
+    (when last-version
+      (save-match-data
+        (string-match "^.*\\([0-9]+\\.[0-9]+\\.[0-9]+\\)$" last-version)
+        (match-string 1 last-version)))))
+
+(defun spacemacs/check-for-new-version (&optional interval)
+  "Periodicly check for new for new Spacemacs version.
+Update `spacemacs-new-version' variable if any new version has been
+found."
+  ;; (message "Start checking for new version...")
+  (async-start
+   (lambda ()
+     (add-to-list 'load-path (concat user-emacs-directory "core/"))
+     (require 'spacemacs-mode)
+     (spacemacs/load-or-install-package 'pcache t)
+     (spacemacs/load-or-install-package 'logito t)
+     (spacemacs/load-or-install-package 'gh t "gh-repos.el")
+     (spacemacs//get-last-version spacemacs-repository
+                                  spacemacs-repository-owner))   
+   (lambda (result)
+     (when result
+       (unless (or (version< result spacemacs-version)
+                   (string= result spacemacs-version)
+                   (if spacemacs-new-version
+                       (string= result spacemacs-new-version)))
+         (message "New version of Spacemacs available: %s" result)
+         (setq spacemacs-new-version result)))))
+  (when interval
+    (setq spacemacs-version-check-timer
+          (run-at-time t (timer-duration interval)
+                       'spacemacs/check-for-new-version))))
+
+(defun spacemacs//deffaces-new-version-lighter (state)
+  "Define a new version lighter face for the given STATE."
+  (let* ((fname (intern (format "spacemacs-mode-line-new-version-lighter-%s-face"
+                                (symbol-name state))))
+         (foreground (face-foreground state)))
+    (eval `(defface ,fname '((t ()))
+             ,(format "Color for new version lighter in mode line (%s)."
+                      (symbol-name state))
+             :group 'spacemacs))
+    (set-face-attribute fname nil
+                        :foreground foreground
+                        :box (face-attribute 'mode-line :box))))
+
+(defun spacemacs/set-new-version-lighter-mode-line-faces ()
+  "Define or set the new version lighter mode-line faces."
+  (mapcar 'spacemacs//deffaces-new-version-lighter
+          '(error warning success)))
+(spacemacs/set-new-version-lighter-mode-line-faces)
+
+(defun spacemacs//compute-version-score (version)
+  "Returns an integer from the version list.
+Example: (1 42 3) = 1 042 003"
+  (let ((result 0)
+        (rev (reverse version)))
+    (dotimes (i 3)
+      (setq result (+ result (* (nth i rev) (expt 10 (* i 3))))))
+    result))
+
+(defun spacemacs//compute-version-score (version)
+  "Returns an integer from the version list.
+Example: (1 42 3) = 1 042 003"
+  (let ((i -1))
+    (reduce '+ (mapcar (lambda (n) (setq i (1+ i)) (* n (expt 10 (* i 3))))
+                       (reverse version)))))
+
+(defun spacemacs/get-new-version-lighter-face (current new)
+  "Return the new version lighter face given the difference between the CURRENT
+version and the NEW version."
+  (let* ((lcur (version-to-list current))
+         (lnew (version-to-list new))
+         (scur (spacemacs//compute-version-score lcur))
+         (snew (spacemacs//compute-version-score lnew))
+         (diff (- snew scur)))
+    (cond
+     ((< diff 3000) 'spacemacs-mode-line-new-version-lighter-success-face)
+     ((< diff 5000) 'spacemacs-mode-line-new-version-lighter-warning-face)
+     (t 'spacemacs-mode-line-new-version-lighter-error-face))))
+
 (defun spacemacs/set-font (font size &optional options)
   (let* ((fontstr (if options
                       (format "%s-%s:%s" font size options)

doc/DOCUMENTATION.md

@@ -739,6 +739,7 @@ Some elements can be dynamically toggled:
 <kbd>SPC t m m</kbd>   | toggle the minor mode lighters
 <kbd>SPC t m b</kbd>   | toggle the battery status
 <kbd>SPC t m f</kbd>   | toggle the flycheck info
+<kbd>SPC t m v</kbd>   | toggle the new version lighter
 
 ### Flycheck integration
 

spacemacs/funcs.el

@@ -157,6 +157,8 @@ changed to THEME."
       (spacemacs/set-state-faces))
   (if (fboundp 'spacemacs/set-flycheck-mode-line-faces)
       (spacemacs/set-flycheck-mode-line-faces))
+  (if (fboundp 'spacemacs/set-new-version-lighter-mode-line-faces)
+      (spacemacs/set-new-version-lighter-mode-line-faces))
   (if (fboundp 'powerline-reset)
       (powerline-reset)))
 

spacemacs/packages.el

@@ -1656,6 +1656,19 @@ determine the state to enable when escaping from the insert state.")
                             (if dotspacemacs-mode-line-unicode-symbols " " "") 'face face)
                            (unless dotspacemacs-mode-line-unicode-symbols "|"))))
 
+      (defpowerline spacemacs-powerline-new-version
+        (propertize
+         spacemacs-version-check-lighter
+         'mouse-face 'mode-line-highlight
+         'help-echo (format "New version %s | Click with mouse-1 to update (Not Yet Implemented)"
+                            spacemacs-new-version)
+         'local-map (let ((map (make-sparse-keymap)))
+                      (define-key map
+                        [mode-line down-mouse-1]
+                        (lambda (event) (interactive "@e") (message "TODO: update"))
+                        )
+                      map)))
+
       (defvar spacemacs-mode-line-minor-modesp t
         "If not nil, minor modes lighter are displayed in the mode-line.")
       (defun spacemacs/mode-line-minor-modes-toggle ()
@@ -1666,6 +1679,16 @@ determine the state to enable when escaping from the insert state.")
           (setq spacemacs-mode-line-minor-modesp t)))
       (evil-leader/set-key "tmm" 'spacemacs/mode-line-minor-modes-toggle)
 
+      (defvar spacemacs-mode-line-new-version-lighterp t
+        "If not nil, new version lighter is displayed in the mode-line.")
+      (defun spacemacs/mode-line-new-version-lighter-toggle ()
+        "Toggle display of new version lighter."
+        (interactive)
+        (if spacemacs-mode-line-new-version-lighterp
+            (setq spacemacs-mode-line-new-version-lighterp nil)
+          (setq spacemacs-mode-line-new-version-lighterp t)))
+      (evil-leader/set-key "tmv" 'spacemacs/mode-line-new-version-lighter-toggle)
+
       ;; for now we hardcode the height value of powerline depending on the
       ;; window system, a better solution would be to compute it correctly
       ;; in powerline package.
@@ -1770,8 +1793,16 @@ determine the state to enable when escaping from the insert state.")
                         (powerline-raw " " line-face))
 
                        (list
-                        (powerline-raw global-mode-string)
-                        (powerline-raw " " line-face))
+                        (unless (equal '("") global-mode-string)
+                          (powerline-raw global-mode-string)
+                          (powerline-raw " " line-face))
+                        ;; new version
+                        (if (and active
+                                 spacemacs-new-version
+                                 spacemacs-mode-line-new-version-lighterp)
+                            (spacemacs-powerline-new-version
+                             (spacemacs/get-new-version-lighter-face
+                              spacemacs-version spacemacs-new-version) 'r)))
 
                        (list
                         ;; percentage in the file