djavu-asus/elpa/highlight-indentation-20210221.1418/highlight-indentation.el

   1 ;;; highlight-indentation.el --- Minor modes for highlighting indentation
   2 ;; Author: Anton Johansson <anton.johansson@gmail.com> - http://antonj.se
   3 ;; Created: Dec 15 23:42:04 2010
   4 ;; Version: 0.7.0
   5 ;; URL: https://github.com/antonj/Highlight-Indentation-for-Emacs
   6 ;;
   7 ;; This program is free software; you can redistribute it and/or
   8 ;; modify it under the terms of the GNU General Public License as
   9 ;; published by the Free Software Foundation; either version 2 of
  10 ;; the License, or (at your option) any later version.
  11 ;;
  12 ;; This program is distributed in the hope that it will be
  13 ;; useful, but WITHOUT ANY WARRANTY; without even the implied
  14 ;; warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR
  15 ;; PURPOSE.  See the GNU General Public License for more details.
  16 ;;
  17 ;;; Commentary:
  18 ;; Customize `highlight-indentation-face', and
  19 ;; `highlight-indentation-current-column-face' to suit your theme.
  20
  21 ;;; Code:
  22
  23 (defgroup highlight-indentation nil
  24   "Highlight Indentation"
  25   :prefix "highlight-indentation-"
  26   :group 'basic-faces)
  27
  28 (defface highlight-indentation-face
  29   ;; Fringe has non intrusive color in most color-themes
  30   '((t :inherit fringe))
  31   "Basic face for highlighting indentation guides."
  32   :group 'highlight-indentation)
  33
  34 (defcustom highlight-indentation-offset
  35   (if (and (boundp 'standard-indent) standard-indent) standard-indent 2)
  36   "Default indentation offset, used if no other can be found from
  37   major mode. This value is always used by
  38   `highlight-indentation-mode' if set buffer local. Set buffer
  39   local with `highlight-indentation-set-offset'"
  40   :type 'integer
  41   :group 'highlight-indentation)
  42
  43 (defcustom highlight-indentation-blank-lines nil
  44   "Show indentation guides on blank lines.  Experimental.
  45
  46 Known issues:
  47 - Doesn't work well with completion popups that use overlays
  48 - Overlays on blank lines sometimes aren't cleaned up or updated perfectly
  49   Can be refreshed by scrolling
  50 - Not yet implemented for highlight-indentation-current-column-mode
  51 - May not work perfectly near the bottom of the screen
  52 - Point appears after indent guides on blank lines"
  53   :type 'boolean
  54   :group 'highlight-indentation)
  55
  56 (defvar highlight-indentation-overlay-priority 1)
  57 (defvar highlight-indentation-current-column-overlay-priority 2)
  58
  59 (defconst highlight-indentation-hooks
  60   '((after-change-functions (lambda (start end length)
  61                               (highlight-indentation-redraw-region
  62                                start end
  63                                'highlight-indentation-overlay
  64                                'highlight-indentation-put-overlays-region))
  65                             t t)
  66     (window-scroll-functions (lambda (win start)
  67                                (highlight-indentation-redraw-window
  68                                 win
  69                                 'highlight-indentation-overlay
  70                                 'highlight-indentation-put-overlays-region
  71                                 start))
  72                              nil t)))
  73
  74 (defun highlight-indentation-get-buffer-windows (&optional all-frames)
  75   "Return a list of windows displaying the current buffer."
  76   (get-buffer-window-list (current-buffer) 'no-minibuf all-frames))
  77
  78 (defun highlight-indentation-delete-overlays-buffer (overlay)
  79   "Delete all overlays in the current buffer."
  80   (save-restriction
  81     (widen)
  82     (highlight-indentation-delete-overlays-region (point-min) (point-max) overlay)))
  83
  84 (defun highlight-indentation-delete-overlays-region (start end overlay)
  85   "Delete overlays between START and END."
  86   (mapc #'(lambda (o)
  87             (if (overlay-get o overlay) (delete-overlay o)))
  88         (overlays-in start end)))
  89
  90 (defun highlight-indentation-redraw-window (win overlay func &optional start)
  91   "Redraw win starting from START."
  92   (highlight-indentation-redraw-region (or start (window-start win)) (window-end win t) overlay func))
  93
  94 (defun highlight-indentation-redraw-region (start end overlay func)
  95   "Erase and read overlays between START and END."
  96   (save-match-data
  97     (save-excursion
  98       (let ((inhibit-point-motion-hooks t)
  99             (start (save-excursion (goto-char start) (beginning-of-line) (point)))
 100
 101             (end (save-excursion (goto-char end) (line-beginning-position 2))))
 102         (highlight-indentation-delete-overlays-region start end overlay)
 103         (funcall func start end overlay)))))
 104
 105 (defun highlight-indentation-redraw-all-windows (overlay func &optional all-frames)
 106   "Redraw the all windows showing the current buffer."
 107   (dolist (win (highlight-indentation-get-buffer-windows all-frames))
 108     (highlight-indentation-redraw-window win overlay func)))
 109
 110 (defun highlight-indentation-put-overlays-region (start end overlay)
 111   "Place overlays between START and END."
 112   (goto-char end)
 113   (let (o ;; overlay
 114         (last-indent 0)
 115         (last-char 0)
 116         (pos (point))
 117         (loop t))
 118     (while (and loop
 119                 (>= pos start))
 120       (save-excursion
 121         (beginning-of-line)
 122         (let ((c 0)
 123               (cur-column (current-column)))
 124           (while (and (setq c (char-after))
 125                       (integerp c)
 126                       (not (= 10 c)) ;; newline
 127                       (= 32 c)) ;; space
 128             (when (= 0 (% cur-column highlight-indentation-offset))
 129               (let ((p (point)))
 130                 (setq o (make-overlay p (+ p 1))))
 131               (overlay-put o overlay t)
 132               (overlay-put o 'priority highlight-indentation-overlay-priority)
 133               (overlay-put o 'face 'highlight-indentation-face))
 134             (forward-char)
 135             (setq cur-column (current-column)))
 136           (when (and highlight-indentation-blank-lines
 137                      (integerp c)
 138                      (or (= 10 c)
 139                          (= 13 c)))
 140             (when (< cur-column last-indent)
 141               (let ((column cur-column)
 142                     (s nil)
 143                     (show t)
 144                     num-spaces)
 145                 (while (< column last-indent)
 146                   (if (>= 0
 147                           (setq num-spaces
 148                                 (%
 149                                  (- last-indent column)
 150                                  highlight-indentation-offset)))
 151                       (progn
 152                         (setq num-spaces (1- highlight-indentation-offset))
 153                         (setq show t))
 154                     (setq show nil))
 155                   (setq s (cons (concat
 156                                  (if show
 157                                      (propertize " "
 158                                                  'face
 159                                                  'highlight-indentation-face)
 160                                    "")
 161                                  (make-string num-spaces 32))
 162                                 s))
 163                   (setq column (+ column num-spaces (if show 1 0))))
 164                 (setq s (apply 'concat (reverse s)))
 165                 (let ((p (point)))
 166                   (setq o (make-overlay p p)))
 167                 (overlay-put o overlay t)
 168                 (overlay-put o 'priority highlight-indentation-overlay-priority)
 169                 (overlay-put o 'after-string s))
 170               (setq cur-column last-indent)))
 171           (setq last-indent (* highlight-indentation-offset
 172                                (ceiling (/ (float cur-column)
 173                                            highlight-indentation-offset))))))
 174       (when (= pos start)
 175         (setq loop nil))
 176       (forward-line -1) ;; previous line
 177       (setq pos (point)))))
 178
 179 (defun highlight-indentation-guess-offset ()
 180   "Get indentation offset of current buffer."
 181   (cond ((and (eq major-mode 'python-mode) (boundp 'python-indent))
 182          python-indent)
 183         ((and (eq major-mode 'python-mode) (boundp 'py-indent-offset))
 184          py-indent-offset)
 185         ((and (eq major-mode 'python-mode) (boundp 'python-indent-offset))
 186          python-indent-offset)
 187         ((and (eq major-mode 'ruby-mode) (boundp 'ruby-indent-level))
 188          ruby-indent-level)
 189         ((and (eq major-mode 'scala-mode) (boundp 'scala-indent:step))
 190          scala-indent:step)
 191         ((and (eq major-mode 'scala-mode) (boundp 'scala-mode-indent:step))
 192          scala-mode-indent:step)
 193         ((and (or (eq major-mode 'scss-mode) (eq major-mode 'css-mode)) (boundp 'css-indent-offset))
 194          css-indent-offset)
 195         ((and (eq major-mode 'nxml-mode) (boundp 'nxml-child-indent))
 196          nxml-child-indent)
 197         ((and (eq major-mode 'coffee-mode) (boundp 'coffee-tab-width))
 198          coffee-tab-width)
 199         ((and (eq major-mode 'js-mode) (boundp 'js-indent-level))
 200          js-indent-level)
 201         ((and (eq major-mode 'js2-mode) (boundp 'js2-basic-offset))
 202          js2-basic-offset)
 203         ((and (fboundp 'derived-mode-class) (eq (derived-mode-class major-mode) 'sws-mode) (boundp 'sws-tab-width))
 204          sws-tab-width)
 205         ((and (eq major-mode 'web-mode) (boundp 'web-mode-markup-indent-offset))
 206          web-mode-markup-indent-offset) ; other similar vars: web-mode-{css-indent,scripts}-offset
 207         ((and (eq major-mode 'web-mode) (boundp 'web-mode-html-offset)) ; old var
 208          web-mode-html-offset)
 209         ((and (local-variable-p 'c-basic-offset) (boundp 'c-basic-offset))
 210          c-basic-offset)
 211         ((and (eq major-mode 'yaml-mode) (boundp 'yaml-indent-offset))
 212          yaml-indent-offset)
 213         ((and (eq major-mode 'elixir-mode) (boundp 'elixir-smie-indent-basic))
 214          elixir-smie-indent-basic)
 215         (t
 216          (default-value 'highlight-indentation-offset))))
 217
 218 ;;;###autoload
 219 (define-minor-mode highlight-indentation-mode
 220   "Highlight indentation minor mode highlights indentation based on spaces"
 221   :lighter " ||"
 222   (when (not highlight-indentation-mode) ;; OFF
 223     (highlight-indentation-delete-overlays-buffer 'highlight-indentation-overlay)
 224     (dolist (hook highlight-indentation-hooks)
 225       (remove-hook (car hook) (nth 1 hook) (nth 3 hook))))
 226
 227   (when highlight-indentation-mode ;; ON
 228     (when (not (local-variable-p 'highlight-indentation-offset))
 229       (set (make-local-variable 'highlight-indentation-offset)
 230            (highlight-indentation-guess-offset)))
 231
 232     ;; Setup hooks
 233     (dolist (hook highlight-indentation-hooks)
 234       (apply 'add-hook hook))
 235     (highlight-indentation-redraw-all-windows 'highlight-indentation-overlay
 236                                               'highlight-indentation-put-overlays-region)))
 237
 238 ;;;###autoload
 239 (defun highlight-indentation-set-offset (offset)
 240   "Set indentation offset locally in buffer, will prevent
 241 highlight-indentation from trying to guess indentation offset
 242 from major mode"
 243   (interactive
 244    (if (and current-prefix-arg (not (consp current-prefix-arg)))
 245        (list (prefix-numeric-value current-prefix-arg))
 246      (list (read-number "Indentation offset: "))))
 247   (set (make-local-variable 'highlight-indentation-offset) offset)
 248   (when highlight-indentation-mode
 249     (highlight-indentation-mode)))
 250
 251 ;;; This minor mode will highlight the indentation of the current line
 252 ;;; as a vertical bar (grey background color) aligned with the column of the
 253 ;;; first character of the current line.
 254 (defface highlight-indentation-current-column-face
 255   ;; Fringe has non intrusive color in most color-themes
 256   '((t (:background "black")))
 257   "Basic face for highlighting indentation guides."
 258   :group 'highlight-indentation)
 259
 260 (defconst highlight-indentation-current-column-hooks
 261   '((post-command-hook (lambda ()
 262                          (highlight-indentation-redraw-all-windows 'highlight-indentation-current-column-overlay
 263                                                                    'highlight-indentation-current-column-put-overlays-region)) nil t)))
 264
 265 (defun highlight-indentation-current-column-put-overlays-region (start end overlay)
 266   "Place overlays between START and END."
 267   (let (o ;; overlay
 268         (last-indent 0)
 269         (indent (save-excursion (back-to-indentation) (current-column)))
 270         (pos start))
 271     (goto-char start)
 272     ;; (message "doing it %d" indent)
 273     (while (< pos end)
 274       (beginning-of-line)
 275       (while (and (integerp (char-after))
 276                   (not (= 10 (char-after))) ;; newline
 277                   (= 32 (char-after))) ;; space
 278         (when (= (current-column) indent)
 279           (setq pos (point)
 280                 last-indent pos
 281                 o (make-overlay pos (+ pos 1)))
 282           (overlay-put o overlay t)
 283           (overlay-put o 'priority highlight-indentation-current-column-overlay-priority)
 284           (overlay-put o 'face 'highlight-indentation-current-column-face))
 285         (forward-char))
 286       (forward-line) ;; Next line
 287       (setq pos (point)))))
 288
 289 ;;;###autoload
 290 (define-minor-mode highlight-indentation-current-column-mode
 291   "Highlight Indentation minor mode displays a vertical bar
 292 corresponding to the indentation of the current line"
 293   :lighter " |"
 294
 295   (when (not highlight-indentation-current-column-mode) ;; OFF
 296     (highlight-indentation-delete-overlays-buffer 'highlight-indentation-current-column-overlay)
 297     (dolist (hook highlight-indentation-current-column-hooks)
 298       (remove-hook (car hook) (nth 1 hook) (nth 3 hook))))
 299
 300   (when highlight-indentation-current-column-mode ;; ON
 301     (when (not (local-variable-p 'highlight-indentation-offset))
 302       (set (make-local-variable 'highlight-indentation-offset)
 303            (highlight-indentation-guess-offset)))
 304
 305     ;; Setup hooks
 306     (dolist (hook highlight-indentation-current-column-hooks)
 307       (apply 'add-hook hook))
 308     (highlight-indentation-redraw-all-windows 'highlight-indentation-current-column-overlay
 309                                               'highlight-indentation-current-column-put-overlays-region)))
 310
 311 (provide 'highlight-indentation)
 312
 313 ;;; highlight-indentation.el ends here