core: add support for mode-line themes

New layer variable `dotspacemacs-mode-line-themes`:

Set the theme for the Spaceline. Supported themes are `spacemacs',
`all-the-icons', `custom', `vim-powerline' and `vanilla'. The first three
are spaceline themes. `vanilla' is default Emacs mode-line. `custom' is a
user defined themes, refer to the DOCUMENTATION.org for more info on how
to create your own spaceline theme."

See DOCUMENTATION.org changes for more info.

This commit adds support for `spaceline-all-the-icons` package.

core/core-dotspacemacs.el

@@ -147,6 +147,13 @@ whenever you start Emacs.")
 Press `SPC T n' to cycle to the next theme in the list (works great
 with 2 themes variants, one dark and one light")
 
+(defvar dotspacemacs-mode-line-theme 'spacemacs
+  "Set the theme for the Spaceline. Supported themes are `spacemacs',
+`all-the-icons', `custom', `vim-powerline' and `vanilla'. The first three
+are spaceline themes. `vanilla' is default Emacs mode-line. `custom' is a
+user defined themes, refer to the DOCUMENTATION.org for more info on how
+to create your own spaceline theme.")
+
 (defvar dotspacemacs-frame-title-format "%I@%S"
   "Default format string for a frame title bar, using the
   original format spec, and additional customizations.")
@@ -741,11 +748,24 @@ error recovery."
   (dotspacemacs||let-init-test
    (dotspacemacs/init)
    (spacemacs//test-var
-    (lambda (x) (or (member x '(vim emacs hybrid))
-                    (and (listp x)
-                         (spacemacs/mplist-get x :variables))))
+    (lambda (x)
+      (or (member x '(vim
+                      emacs
+                      hybrid))
+          (and (listp x)
+               (eq 'hybrid (car x))
+               (spacemacs/mplist-get x :variables))))
     'dotspacemacs-editing-style
     "is \'vim, \'emacs or \'hybrid or and list with `:variable' keyword")
+   (spacemacs//test-var
+    (lambda (x)
+      (member x '(spacemacs
+                  all-the-icons
+                  custom
+                  vim-powerline
+                  vanilla)))
+    'dotspacemacs-mode-line-theme
+    "is \'spacemacs, \'all-the-icons, \'custom, \'vim-powerline or 'vanilla")
    (spacemacs//test-var
     (lambda (x) (member x '(original cache nil)))
     'dotspacemacs-auto-save-file-location (concat "is one of \'original, "

core/templates/.spacemacs.template

@@ -135,6 +135,12 @@ It should only modify the values of Spacemacs settings."
    ;; with 2 themes variants, one dark and one light)
    dotspacemacs-themes '(spacemacs-dark
                          spacemacs-light)
+   ;; Set the theme for the Spaceline. Supported themes are `spacemacs',
+   ;; `all-the-icons', `custom', `vim-powerline' and `vanilla'. The first three
+   ;; are spaceline themes. `vanilla' is default Emacs mode-line. `custom' is a
+   ;; user defined themes, refer to the DOCUMENTATION.org for more info on how
+   ;; to create your own spaceline theme.. (default 'spacemacs)
+   dotspacemacs-mode-line-theme 'spacemacs
    ;; If non-nil the cursor color matches the state color in GUI Emacs.
    ;; (default t)
    dotspacemacs-colorize-cursor-according-to-state t

doc/DOCUMENTATION.org

@@ -73,15 +73,15 @@
   - [[#gui-toggles][GUI Toggles]]
     - [[#global-line-numbers][Global line numbers]]
   - [[#mode-line][Mode-line]]
-    - [[#powerline-font-installation-for-terminal-mode-users][Powerline font installation for terminal-mode users]]
-    - [[#flycheck-integration][Flycheck integration]]
-    - [[#anzu-integration][Anzu integration]]
-    - [[#battery-status-integration][Battery status integration]]
-    - [[#powerline-separators][Powerline separators]]
-    - [[#minor-modes][Minor Modes]]
-    - [[#customizing-the-mode-line][Customizing the mode-line]]
-      - [[#spaceline][Spaceline]]
-      - [[#restore-lighters][Restore lighters]]
+    - [[#mode-line-themes][Mode-line themes]]
+    - [[#spacemacs-mode-line-theme][Spacemacs mode-line theme]]
+      - [[#powerline-font-installation-for-terminal-mode-users][Powerline font installation for terminal-mode users]]
+      - [[#flycheck-integration][Flycheck integration]]
+      - [[#anzu-integration][Anzu integration]]
+      - [[#battery-status-integration][Battery status integration]]
+      - [[#powerline-separators][Powerline separators]]
+      - [[#minor-modes][Minor Modes]]
+    - [[#custom-spaceline-theme][Custom spaceline theme]]
   - [[#frame-title][Frame title]]
     - [[#iconified-tabified-title][Iconified (tabified) title]]
 - [[#layouts-and-workspaces][Layouts and workspaces]]
@@ -1261,6 +1261,31 @@ Enable line numbers only in programming modes, except for c-mode and c++ mode:
 #+END_SRC
 
 ** Mode-line
+*** Mode-line themes
+Spacemacs supports different mode-line themes. The mode-line theme is set in the
+dotfile with the variable =dotspacemacs-mode-line-theme=.
+
+Currently supported themes are:
+- spaceline themes: =spacemacs=, =all-the-icons=, =custom=
+- a powerline theme: =vim-powerline=
+- no theme at all: =vanilla=
+
+The default theme is =spacemacs= and this theme is described in more detailed in
+the next section.
+
+=all-the-icons= is the theme defined in the package [[https://github.com/domtronn/spaceline-all-the-icons.el][spaceline-all-the-icons]].
+
+=custom= is a user custom spaceline theme, see the guide in the following section.
+
+=vim-powerline= is for the Vim users who are nostalgic of the good old Vim
+powerline.
+
+=vanilla= is the stock mode-line that comes with Emacs.
+
+For now, a restart of Emacs is required whenever you change the theme of your
+mode-line.
+
+*** Spacemacs mode-line theme
 The mode line is a heavily customized [[https://github.com/milkypostman/powerline][powerline]] with the following capabilities:
   - show the window number
   - color code for current state
@@ -1298,19 +1323,19 @@ Some elements can be dynamically toggled:
 | ~SPC t m v~ | toggle the version control info                                 |
 | ~SPC t m V~ | toggle the new version lighter                                  |
 
-*** Powerline font installation for terminal-mode users
+**** Powerline font installation for terminal-mode users
 Users who run Emacs in terminal mode may need to install the [[https://github.com/powerline/fonts][Powerline patched
 fonts]] and configure their terminal clients to use them to make the Powerline
 separators render correctly.
 
-*** Flycheck integration
+**** Flycheck integration
 When [[https://github.com/flycheck/flycheck][Flycheck]] minor mode is enabled, a new element appears showing the number of
 errors, warnings and info.
 
 [[file:img/powerline-wave.png]]
 /Flycheck integration in mode-line/
 
-*** Anzu integration
+**** Anzu integration
 [[https://github.com/syohex/emacs-anzu][Anzu]] shows the number of occurrence when performing a search. Spacemacs
 integrates the Anzu status nicely by displaying it temporarily when ~n~ or ~N~
 are being pressed. See the =5/6= segment on the screenshot below.
@@ -1318,7 +1343,7 @@ are being pressed. See the =5/6= segment on the screenshot below.
 [[file:img/powerline-anzu.png]]
 /Anzu integration in mode-line/
 
-*** Battery status integration
+**** Battery status integration
 [[https://github.com/lunaryorn/fancy-battery.el][fancy-battery]] displays the percentage of total charge of the battery as well as
 the time remaining to charge or discharge completely the battery.
 
@@ -1332,7 +1357,7 @@ A color code is used for the battery status:
 
 *Note*: These colors may vary depending on your theme.
 
-*** Powerline separators
+**** Powerline separators
 It is possible to easily customize the =powerline separator= by setting the
 =powerline-default-separator= variable in your =~/.spacemacs= and then
 recompiling the modeline. For instance, if you want to set back the separator to
@@ -1368,7 +1393,7 @@ powerline, here is an exhaustive set of screenshots:
 | =zigzag=     | [[file:img/powerline-zigzag.png]]     |
 | =nil=        | [[file:img/powerline-nil.png]]        |
 
-*** Minor Modes
+**** Minor Modes
 Spacemacs uses [[https://www.emacswiki.org/emacs/DiminishedModes][diminish]] mode to reduce the size of minor mode indicators:
 
 The minor mode area can be toggled on and off with ~SPC t m m~
@@ -1419,33 +1444,27 @@ squared symbols like =🅿=.
 | ~SPC t C-W~ | =Ⓦ=     | W     | automatic whitespace cleanup globally                                |
 | ~SPC t y~   | =ⓨ=     | y     | [[https://github.com/capitaomorte/yasnippet][yasnippet]] mode                                                       |
 
-*** Customizing the mode-line
-**** Spaceline
-Spacemacs uses [[https://github.com/TheBB/spaceline][Spaceline]] to provide its mode-line. It consists of a number of
-/segments/ arranged on the left and right sides. These are defined in the
-variables =spaceline-left= and =spaceline-right=. Segments can be defined using
-=spaceline-define-segment=, and added to the appropriate location in the left or
-right hand side variables.
+*** Custom spaceline theme
+You can create your own Spaceline theme by setting the variable
+=dotspacemacs-mode-line-theme= to =custom= and define a function called
+=spaceline-custom-theme= in your =dotspacemacs/user-init= function of your
+dotfile. This functions must accept a variadic number of arguments which are
+additional segments added by Spacemacs (like a segment to notify about available
+updates etc...).
 
-Please see the Spaceline documentation for more information.
-
-**** Restore lighters
-Lighters are abbreviations displayed in the mode-line to identify running minor
-modes. Spacemacs diminishes most of them to make them more compact.
-
-If you want to restore the original lighter of a mode then use the function
-=spacemacs/diminish-undo= with the appropriate mode name.
-
-For example to undo diminish for =company=:
+Example:
 
 #+BEGIN_SRC emacs-lisp
-(spacemacs|use-package-add-hook company
-    :post-config (spacemacs/diminish-undo 'company-mode))
+(defun spaceline-custom-theme (&rest additional-segments)
+    "My custom spaceline theme."
+    (spaceline-compile
+      `(major-mode (minor-modes :when active) buffer-id)
+      `((line-column :separator " | " :priority 3)
+        ,@additional-segments))
+    (setq-default mode-line-format '("%e" (:eval (spaceline-ml-main)))))
 #+END_SRC
 
-Note that we use a =use-package= post init hook to be sure to override any
-lazily diminished lighters (see [[https://github.com/syl20bnr/spacemacs/blob/develop/doc/LAYERS.org][layers documentation]] for more information
-about lazy loading).
+Restart Emacs and enjoy your very own mode-line!
 
 ** Frame title
 Default frame title displays name of current process and hostname of system. You

layers/+spacemacs/spacemacs-modeline/funcs.el

@@ -51,3 +51,15 @@
                             unicode
                           (if ascii ascii unicode))))
               (diminish mode dim))))))))
+
+
+;; Vim powerline
+
+(defun spacemacs//set-vimish-powerline-for-startup-buffers ()
+  "Set the powerline for buffers created when Emacs starts."
+  (dolist (buffer '("*Messages*" "*spacemacs*" "*Compile-Log*"))
+    (when (get-buffer buffer)
+      (with-current-buffer buffer
+        (setq-local mode-line-format (default-value 'mode-line-format))
+        (powerline-set-selected-window)
+        (powerline-reset)))))

layers/+spacemacs/spacemacs-modeline/packages.el

@@ -11,11 +11,19 @@
 
 (setq spacemacs-modeline-packages
       '(
+        anzu
         fancy-battery
+        neotree
         spaceline
+        spaceline-all-the-icons
         symon
+        (vim-powerline :location local)
         ))
 
+(defun spacemacs-modeline/post-init-anzu ()
+  (when (eq 'all-the-icons dotspacemacs-mode-line-theme)
+    (spaceline-all-the-icons--setup-anzu)))
+
 (defun spacemacs-modeline/init-fancy-battery ()
   (use-package fancy-battery
     :defer t
@@ -27,8 +35,13 @@
         :evil-leader "tmb")
       (setq-default fancy-battery-show-percentage t))))
 
+(defun spacemacs-modeline/post-init-neotree ()
+  (when (eq 'all-the-icons dotspacemacs-mode-line-theme)
+    (spaceline-all-the-icons--setup-neotree)))
+
 (defun spacemacs-modeline/init-spaceline ()
   (use-package spaceline-config
+    :if (memq dotspacemacs-mode-line-theme '(spaceline all-the-icons custom))
     :init
     (progn
       (add-hook 'spacemacs-post-user-config-hook 'spaceline-compile)
@@ -97,8 +110,9 @@
           (spacemacs-powerline-new-version
            (spacemacs/get-new-version-lighter-face
             spacemacs-version spacemacs-new-version))))
-      (apply #'spaceline-spacemacs-theme
-             spacemacs-spaceline-additional-segments)
+      (let ((theme (intern (format "spaceline-%S-theme"
+                                   dotspacemacs-mode-line-theme))))
+        (apply theme spacemacs-spaceline-additional-segments))
       ;; Additional spacelines
       (when (package-installed-p 'helm)
         (spaceline-helm-mode t))
@@ -108,6 +122,19 @@
       ;; spaceline
       (spacemacs//set-powerline-for-startup-buffers))))
 
+(defun spacemacs-modeline/pre-init-spaceline-all-the-icons ()
+  (when (eq 'all-the-icons dotspacemacs-mode-line-theme)
+    (spacemacs|use-package-add-hook spaceline-config
+      :pre-config
+      (progn
+        (require 'spaceline-all-the-icons)
+        (spaceline-all-the-icons--setup-git-ahead)))))
+
+(defun spacemacs-modeline/init-spaceline-all-the-icons ()
+  (use-package spaceline-all-the-icons
+    :defer t
+    :init (setq spaceline-all-the-icons-separator-type 'cup)))
+
 (defun spacemacs-modeline/init-symon ()
   (use-package symon
     :defer t
@@ -118,3 +145,29 @@
       (spacemacs|add-toggle minibuffer-system-monitor
         :mode symon-mode
         :evil-leader "tms"))))
+
+(defun spacemacs-modeline/init-vim-powerline ()
+  (when (eq 'vim-powerline dotspacemacs-mode-line-theme)
+    (require 'powerline)
+    (if (display-graphic-p)
+        (setq powerline-default-separator 'arrow)
+      (setq powerline-default-separator 'utf-8))
+    (defun powerline-raw (str &optional face pad)
+      "Render STR as mode-line data using FACE and optionally
+PAD import on left (l) or right (r) or left-right (lr)."
+      (when str
+        (let* ((rendered-str (format-mode-line str))
+               (padded-str (concat
+                            (when (and (> (length rendered-str) 0)
+                                       (or (eq pad 'l) (eq pad 'lr))) " ")
+                            (if (listp str) rendered-str str)
+                            (when (and (> (length rendered-str) 0)
+                                       (or (eq pad 'r) (eq pad 'lr))) " "))))
+
+          (if face
+              (pl/add-text-property padded-str 'face face)
+            padded-str))))
+    (require 'vim-powerline-theme)
+    (powerline-vimish-theme)
+    (add-hook 'emacs-startup-hook
+              'spacemacs//set-vimish-powerline-for-startup-buffers)))

layers/+vim/vim-powerline/README.org

@@ -1,13 +0,0 @@
-#+TITLE: vim-powerline layer
-
-* Table of Contents                                         :TOC_4_gh:noexport:
-- [[#description][Description]]
-- [[#install][Install]]
-
-* Description
-A powerline theme modeled after the vim powerline theme.
-
-* Install
-To use this configuration layer, add it to your =~/.spacemacs=. You will need to
-add =vim-powerline= to the existing =dotspacemacs-configuration-layers= list in this
-file.

layers/+vim/vim-powerline/packages.el

@@ -1,43 +0,0 @@
-(setq vim-powerline-packages
-      '(
-        powerline
-        (vim-powerline :location local)
-        ))
-
-(defun vim-powerline/init-powerline ())
-
-(defun vim-powerline/init-vim-powerline ()
-  (require 'powerline)
-  (if (display-graphic-p)
-      (setq powerline-default-separator 'arrow)
-    (setq powerline-default-separator 'utf-8))
-
-  (defun powerline-raw (str &optional face pad)
-  "Render STR as mode-line data using FACE and optionally
-PAD import on left (l) or right (r) or left-right (lr)."
-  (when str
-    (let* ((rendered-str (format-mode-line str))
-           (padded-str (concat
-                        (when (and (> (length rendered-str) 0)
-                                   (or (eq pad 'l) (eq pad 'lr))) " ")
-                        (if (listp str) rendered-str str)
-                        (when (and (> (length rendered-str) 0)
-                                   (or (eq pad 'r) (eq pad 'lr))) " "))))
-
-      (if face
-          (pl/add-text-property padded-str 'face face)
-        padded-str))))
-
-  (require 'vim-powerline-theme)
-  (powerline-vimish-theme)
-
-  (defun spacemacs//set-vimish-powerline-for-startup-buffers ()
-    "Set the powerline for buffers created when Emacs starts."
-    (dolist (buffer '("*Messages*" "*spacemacs*" "*Compile-Log*"))
-      (when (get-buffer buffer)
-        (with-current-buffer buffer
-          (setq-local mode-line-format (default-value 'mode-line-format))
-          (powerline-set-selected-window)
-          (powerline-reset)))))
-  (add-hook 'emacs-startup-hook
-            'spacemacs//set-vimish-powerline-for-startup-buffers))