code.delx.au - gnu-emacs-elpa/blob - context-coloring.el

   1 ;;; context-coloring.el --- Highlight by scope  -*- lexical-binding: t; -*-
   2
   3 ;; Copyright (C) 2014-2015  Free Software Foundation, Inc.
   4
   5 ;; Author: Jackson Ray Hamilton <jackson@jacksonrayhamilton.com>
   6 ;; Version: 6.2.1
   7 ;; Keywords: convenience faces tools
   8 ;; Package-Requires: ((emacs "24") (js2-mode "20150126"))
   9 ;; URL: https://github.com/jacksonrayhamilton/context-coloring
  10
  11 ;; This file is part of GNU Emacs.
  12
  13 ;; This program is free software; you can redistribute it and/or modify
  14 ;; it under the terms of the GNU General Public License as published by
  15 ;; the Free Software Foundation, either version 3 of the License, or
  16 ;; (at your option) any later version.
  17
  18 ;; This program is distributed in the hope that it will be useful,
  19 ;; but WITHOUT ANY WARRANTY; without even the implied warranty of
  20 ;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  21 ;; GNU General Public License for more details.
  22
  23 ;; You should have received a copy of the GNU General Public License
  24 ;; along with this program.  If not, see <http://www.gnu.org/licenses/>.
  25
  26 ;;; Commentary:
  27
  28 ;; Highlights code by scope.  Top-level scopes are one color, second-level
  29 ;; scopes are another color, and so on.  Variables retain the color of the scope
  30 ;; in which they are defined.  A variable defined in an outer scope referenced
  31 ;; by an inner scope is colored the same as the outer scope.
  32
  33 ;; By default, comments and strings are still highlighted syntactically.
  34
  35 ;; To use with js2-mode, add the following to your init file:
  36
  37 ;; (require 'context-coloring)
  38 ;; (add-hook 'js2-mode-hook 'context-coloring-mode)
  39
  40 ;; To use with js-mode or js3-mode, install Node.js 0.10+ and the scopifier
  41 ;; executable:
  42
  43 ;; $ npm install -g scopifier
  44
  45 ;;; Code:
  46
  47 (require 'js2-mode)
  48
  49
  50 ;;; Local variables
  51
  52 (defvar-local context-coloring-buffer nil
  53   "Reference to this buffer (for timers).")
  54
  55
  56 ;;; Utilities
  57
  58 (defun context-coloring-join (strings delimiter)
  59   "Join a list of STRINGS with the string DELIMITER."
  60   (mapconcat 'identity strings delimiter))
  61
  62 (defsubst context-coloring-trim-right (string)
  63   "Remove leading whitespace from STRING."
  64   (if (string-match "[ \t\n\r]+\\'" string)
  65       (replace-match "" t t string)
  66     string))
  67
  68 (defsubst context-coloring-trim-left (string)
  69   "Remove trailing whitespace from STRING."
  70   (if (string-match "\\`[ \t\n\r]+" string)
  71       (replace-match "" t t string)
  72     string))
  73
  74 (defsubst context-coloring-trim (string)
  75   "Remove leading and trailing whitespace from STRING."
  76   (context-coloring-trim-left (context-coloring-trim-right string)))
  77
  78
  79 ;;; Faces
  80
  81 (defun context-coloring-defface (level tty light dark)
  82   "Define a face for LEVEL with colors for TTY, LIGHT and DARK
  83 backgrounds."
  84   (let ((face (intern (format "context-coloring-level-%s-face" level)))
  85         (doc (format "Context coloring face, level %s." level)))
  86     (custom-declare-face
  87      face
  88      `((((type tty)) (:foreground ,tty))
  89        (((background light)) (:foreground ,light))
  90        (((background dark)) (:foreground ,dark)))
  91      doc
  92      :group 'context-coloring)))
  93
  94 (defun context-coloring-defface-neutral (level)
  95   "Define a face for LEVEL with the default neutral colors."
  96   (context-coloring-defface level nil "#3f3f3f" "#cdcdcd"))
  97
  98 (context-coloring-defface 0 nil       "#000000" "#ffffff")
  99 (context-coloring-defface 1 "yellow"  "#008b8b" "#00ffff")
 100 (context-coloring-defface 2 "green"   "#0000ff" "#87cefa")
 101 (context-coloring-defface 3 "cyan"    "#483d8b" "#b0c4de")
 102 (context-coloring-defface 4 "blue"    "#a020f0" "#eedd82")
 103 (context-coloring-defface 5 "magenta" "#a0522d" "#98fb98")
 104 (context-coloring-defface 6 "red"     "#228b22" "#7fffd4")
 105 (context-coloring-defface-neutral 7)
 106
 107 (defvar context-coloring-maximum-face nil
 108   "Index of the highest face available for coloring.")
 109
 110 (defvar context-coloring-original-maximum-face nil
 111   "Fallback value for `context-coloring-maximum-face' when all
 112   themes have been disabled.")
 113
 114 (setq context-coloring-maximum-face 7)
 115
 116 (setq context-coloring-original-maximum-face
 117       context-coloring-maximum-face)
 118
 119 ;; Theme authors can have up to 26 levels: 1 (0th) for globals, 24 (1st-24th)
 120 ;; for nested levels, and 1 (25th) for infinity.
 121 (dotimes (number 18)
 122   (context-coloring-defface-neutral (+ number context-coloring-maximum-face 1)))
 123
 124
 125 ;;; Face functions
 126
 127 (defsubst context-coloring-level-face (level)
 128   "Return the symbol for a face with LEVEL."
 129   ;; `concat' is faster than `format' here.
 130   (intern-soft
 131    (concat "context-coloring-level-" (number-to-string level) "-face")))
 132
 133 (defsubst context-coloring-bounded-level-face (level)
 134   "Return the symbol for a face with LEVEL, bounded by
 135 `context-coloring-maximum-face'."
 136   (context-coloring-level-face (min level context-coloring-maximum-face)))
 137
 138
 139 ;;; Colorization utilities
 140
 141 (defsubst context-coloring-colorize-region (start end level)
 142   "Color characters from the 1-indexed START point (inclusive) to
 143 the END point (exclusive) with the face corresponding to LEVEL."
 144   (add-text-properties
 145    start
 146    end
 147    `(face ,(context-coloring-bounded-level-face level))))
 148
 149 (defcustom context-coloring-comments-and-strings nil
 150   "If non-nil, also color comments and strings using `font-lock'."
 151   :group 'context-coloring)
 152
 153 (make-obsolete-variable
 154  'context-coloring-comments-and-strings
 155  "use `context-coloring-syntactic-comments' and
 156  `context-coloring-syntactic-strings' instead."
 157  "6.1.0")
 158
 159 (defcustom context-coloring-syntactic-comments t
 160   "If non-nil, also color comments using `font-lock'."
 161   :group 'context-coloring)
 162
 163 (defcustom context-coloring-syntactic-strings t
 164   "If non-nil, also color strings using `font-lock'."
 165   :group 'context-coloring)
 166
 167 (defun context-coloring-font-lock-syntactic-comment-function (state)
 168   "Tell `font-lock' to color a comment but not a string."
 169   (if (nth 3 state) nil font-lock-comment-face))
 170
 171 (defun context-coloring-font-lock-syntactic-string-function (state)
 172   "Tell `font-lock' to color a string but not a comment."
 173   (if (nth 3 state) font-lock-string-face nil))
 174
 175 (defsubst context-coloring-maybe-colorize-comments-and-strings ()
 176   "Color the current buffer's comments and strings if
 177 `context-coloring-comments-and-strings' is non-nil."
 178   (when (or context-coloring-comments-and-strings
 179             context-coloring-syntactic-comments
 180             context-coloring-syntactic-strings)
 181     (let ((old-function font-lock-syntactic-face-function)
 182           saved-function-p)
 183       (cond
 184        ((and context-coloring-syntactic-comments
 185              (not context-coloring-syntactic-strings))
 186         (setq font-lock-syntactic-face-function
 187               'context-coloring-font-lock-syntactic-comment-function)
 188         (setq saved-function-p t))
 189        ((and context-coloring-syntactic-strings
 190              (not context-coloring-syntactic-comments))
 191         (setq font-lock-syntactic-face-function
 192               'context-coloring-font-lock-syntactic-string-function)
 193         (setq saved-function-p t)))
 194       (save-excursion
 195         (font-lock-fontify-syntactically-region (point-min) (point-max)))
 196       (when saved-function-p
 197         (setq font-lock-syntactic-face-function old-function)))))
 198
 199
 200 ;;; js2-mode colorization
 201
 202 (defvar-local context-coloring-js2-scope-level-hash-table nil
 203   "Associate `js2-scope' structures and with their scope
 204   levels.")
 205
 206 (defcustom context-coloring-js-block-scopes nil
 207   "If non-nil, also color block scopes in the scope hierarchy in JavaScript.
 208
 209 The block-scoped `let' and `const' are introduced in ES6.  Enable
 210 this for ES6 code; disable it elsewhere.
 211
 212 Supported modes: `js2-mode'"
 213   :group 'context-coloring)
 214
 215 (defsubst context-coloring-js2-scope-level (scope)
 216   "Return the level of SCOPE."
 217   (cond ((gethash scope context-coloring-js2-scope-level-hash-table))
 218         (t
 219          (let ((level 0)
 220                (current-scope scope)
 221                enclosing-scope)
 222            (while (and current-scope
 223                        (js2-node-parent current-scope)
 224                        (setq enclosing-scope
 225                              (js2-node-get-enclosing-scope current-scope)))
 226              (when (or context-coloring-js-block-scopes
 227                        (let ((type (js2-scope-type current-scope)))
 228                          (or (= type js2-SCRIPT)
 229                              (= type js2-FUNCTION)
 230                              (= type js2-CATCH))))
 231                (setq level (+ level 1)))
 232              (setq current-scope enclosing-scope))
 233            (puthash scope level context-coloring-js2-scope-level-hash-table)))))
 234
 235 (defsubst context-coloring-js2-local-name-node-p (node)
 236   "Determine if NODE is a `js2-name-node' representing a local
 237 variable."
 238   (and (js2-name-node-p node)
 239        (let ((parent (js2-node-parent node)))
 240          (not (or (and (js2-object-prop-node-p parent)
 241                        (eq node (js2-object-prop-node-left parent)))
 242                   (and (js2-prop-get-node-p parent)
 243                        ;; For nested property lookup, the node on the left is a
 244                        ;; `js2-prop-get-node', so this always works.
 245                        (eq node (js2-prop-get-node-right parent))))))))
 246
 247 (defvar-local context-coloring-point-max nil
 248   "Cached value of `point-max'.")
 249
 250 (defsubst context-coloring-js2-colorize-node (node level)
 251   "Color NODE with the color for LEVEL."
 252   (let ((start (js2-node-abs-pos node)))
 253     (context-coloring-colorize-region
 254      start
 255      (min
 256       ;; End
 257       (+ start (js2-node-len node))
 258       ;; Somes nodes (like the ast when there is an unterminated multiline
 259       ;; comment) will stretch to the value of `point-max'.
 260       context-coloring-point-max)
 261      level)))
 262
 263 (defun context-coloring-js2-colorize ()
 264   "Color the current buffer using the abstract syntax tree
 265 generated by `js2-mode'."
 266   ;; Reset the hash table; the old one could be obsolete.
 267   (setq context-coloring-js2-scope-level-hash-table (make-hash-table :test 'eq))
 268   (setq context-coloring-point-max (point-max))
 269   (with-silent-modifications
 270     (js2-visit-ast
 271      js2-mode-ast
 272      (lambda (node end-p)
 273        (when (null end-p)
 274          (cond
 275           ((js2-scope-p node)
 276            (context-coloring-js2-colorize-node
 277             node
 278             (context-coloring-js2-scope-level node)))
 279           ((context-coloring-js2-local-name-node-p node)
 280            (let* ((enclosing-scope (js2-node-get-enclosing-scope node))
 281                   (defining-scope (js2-get-defining-scope
 282                                    enclosing-scope
 283                                    (js2-name-node-name node))))
 284              ;; The tree seems to be walked lexically, so an entire scope will
 285              ;; be colored, including its name nodes, before they are reached.
 286              ;; Coloring the nodes defined in that scope would be redundant, so
 287              ;; don't do it.
 288              (when (not (eq defining-scope enclosing-scope))
 289                (context-coloring-js2-colorize-node
 290                 node
 291                 (context-coloring-js2-scope-level defining-scope))))))
 292          ;; The `t' indicates to search children.
 293          t)))
 294     (context-coloring-maybe-colorize-comments-and-strings)))
 295
 296
 297 ;;; Emacs Lisp colorization
 298
 299 (defun context-coloring-make-scope (depth level)
 300   (list
 301    :depth depth
 302    :level level
 303    :variables (make-hash-table)))
 304
 305 (defun context-coloring-scope-get-depth (scope)
 306   (plist-get scope :depth))
 307
 308 (defun context-coloring-scope-get-level (scope)
 309   (plist-get scope :level))
 310
 311 (defun context-coloring-scope-add-variable (scope variable)
 312   (puthash variable t (plist-get scope :variables)))
 313
 314 (defun context-coloring-scope-get-variable (scope variable)
 315   (gethash variable (plist-get scope :variables)))
 316
 317 (defun context-coloring-get-variable-level (scope-stack variable)
 318   (let* (scope
 319          level)
 320     (while (and scope-stack (not level))
 321       (setq scope (car scope-stack))
 322       (cond
 323        ((context-coloring-scope-get-variable scope variable)
 324         (setq level (context-coloring-scope-get-level scope)))
 325        (t
 326         (setq scope-stack (cdr scope-stack)))))
 327     ;; Assume a global variable.
 328     (or level 0)))
 329
 330 (defun context-coloring-make-backtick (end enabled)
 331   (list
 332    :end end
 333    :enabled enabled))
 334
 335 (defun context-coloring-backtick-get-end (backtick)
 336   (plist-get backtick :end))
 337
 338 (defun context-coloring-backtick-get-enabled (backtick)
 339   (plist-get backtick :enabled))
 340
 341 (defun context-coloring-backtick-enabled-p (backtick-stack)
 342   (context-coloring-backtick-get-enabled (car backtick-stack)))
 343
 344 (defun context-coloring-forward-sws ()
 345   "Move forward through whitespace and comments."
 346   (while (forward-comment 1)))
 347
 348 (defun context-coloring-forward-sexp-position ()
 349   (scan-sexps (point) 1))
 350
 351 (defun context-coloring-emacs-lisp-identifier-syntax-p (syntax-code)
 352   (or (= 2 syntax-code)
 353       (= 3 syntax-code)))
 354
 355 (defun context-coloring-open-parenthesis-p (syntax-code)
 356   (= 4 syntax-code))
 357
 358 (defun context-coloring-close-parenthesis-p (syntax-code)
 359   (= 5 syntax-code))
 360
 361 (defun context-coloring-expression-prefix-p (syntax-code)
 362   (= 6 syntax-code))
 363
 364 (defun context-coloring-at-open-parenthesis-p ()
 365   (= 4 (logand #xFFFF (car (syntax-after (point))))))
 366
 367 (defun context-coloring-ppss-depth (ppss)
 368   ;; Same as (nth 0 ppss).
 369   (car ppss))
 370
 371 (defconst context-coloring-defun-regexp
 372   "\\`defun\\'\\|\\`defmacro\\'\\|\\`defsubst\\'")
 373
 374 (defconst context-coloring-arglist-arg-regexp
 375   "\\`[^&:]")
 376
 377 (defconst context-coloring-unbindable-constant-regexp
 378   "\\`[-+]?[0-9]\\|\\`t\\'\\|\\`nil\\'")
 379
 380 (defconst context-coloring-COMMA-CHAR 44)
 381 (defconst context-coloring-BACKTICK-CHAR 96)
 382
 383 (defun context-coloring-emacs-lisp-colorize ()
 384   "Color the current buffer by parsing emacs lisp sexps."
 385   (with-silent-modifications
 386     (save-excursion
 387       ;; TODO: Can probably make this lazy to the nearest defun.
 388       (goto-char (point-min))
 389       (let* ((inhibit-point-motion-hooks t)
 390              (end (point-max))
 391              (last-ppss-pos (point))
 392              (ppss (syntax-ppss))
 393              ; -1 never matches a depth.  This is a minor optimization.
 394              (scope-stack `(,(context-coloring-make-scope -1 0)))
 395              (backtick-stack '())
 396              one-word-found-p
 397              in-defun-p
 398              in-lambda-p
 399              in-let-p
 400              in-let*-p
 401              defun-arglist
 402              defun-arg
 403              let-varlist
 404              let-var
 405              variable
 406              variable-end
 407              variable-string
 408              variable-scope-level
 409              token-pos
 410              token-syntax
 411              token-syntax-code
 412              token-char
 413              child-0-pos
 414              child-0-end
 415              child-0-syntax
 416              child-0-syntax-code
 417              child-0-string
 418              child-1-pos
 419              child-1-end
 420              child-1-syntax
 421              child-1-syntax-code
 422              child-2-end)
 423         (while (> end (progn (skip-syntax-forward "^()w_'" end)
 424                              (point)))
 425           (setq token-pos (point))
 426           (setq token-syntax (syntax-after token-pos))
 427           (setq token-syntax-code (logand #xFFFF (car token-syntax)))
 428           (setq token-char (char-after))
 429           (setq ppss (parse-partial-sexp last-ppss-pos token-pos nil nil ppss))
 430           (setq last-ppss-pos token-pos)
 431           (cond
 432
 433            ;; Resolve an invalid state.
 434            ((cond
 435              ;; Inside string?
 436              ((nth 3 ppss)
 437               (skip-syntax-forward "^\"" end)
 438               (forward-char)
 439               t)
 440              ;; Inside comment?
 441              ((nth 4 ppss)
 442               (skip-syntax-forward "^>" end)
 443               t)))
 444
 445            ;; Need to check early in case there's a comma.
 446            ((context-coloring-expression-prefix-p token-syntax-code)
 447             (forward-char)
 448             (cond
 449              ;; Skip top-level symbols.
 450              ((not (or backtick-stack
 451                        (= token-char context-coloring-BACKTICK-CHAR)))
 452               (goto-char (context-coloring-forward-sexp-position)))
 453              ;; Push a backtick state.
 454              ((or (= token-char context-coloring-BACKTICK-CHAR)
 455                   (= token-char context-coloring-COMMA-CHAR))
 456               (setq backtick-stack (cons (context-coloring-make-backtick
 457                                           (context-coloring-forward-sexp-position)
 458                                           (= token-char context-coloring-BACKTICK-CHAR))
 459                                          backtick-stack)))))
 460
 461            ;; Pop a backtick state.
 462            ((and backtick-stack
 463                  (>= (point) (context-coloring-backtick-get-end (car backtick-stack))))
 464             (setq backtick-stack (cdr backtick-stack)))
 465
 466            ;; Restricted by an enabled backtick.
 467            ((and backtick-stack
 468                  (context-coloring-backtick-enabled-p backtick-stack))
 469             (forward-char))
 470
 471            ((context-coloring-open-parenthesis-p token-syntax-code)
 472             (forward-char)
 473             ;; Look for function calls.
 474             (context-coloring-forward-sws)
 475             (setq child-0-pos (point))
 476             (setq child-0-syntax (syntax-after child-0-pos))
 477             (setq child-0-syntax-code (logand #xFFFF (car child-0-syntax)))
 478             (cond
 479              ((context-coloring-emacs-lisp-identifier-syntax-p child-0-syntax-code)
 480               (setq one-word-found-p t)
 481               (setq child-0-end (scan-sexps child-0-pos 1))
 482               (setq child-0-string (buffer-substring-no-properties child-0-pos child-0-end))
 483               (cond
 484                ((string-match-p context-coloring-defun-regexp child-0-string)
 485                 (setq in-defun-p t))
 486                ((string-match-p "\\`lambda\\'" child-0-string)
 487                 (setq in-lambda-p t))
 488                ((string-match-p "\\`let\\'" child-0-string)
 489                 (setq in-let-p t))
 490                ((string-match-p "\\`let\\*\\'" child-0-string)
 491                 (setq in-let*-p t)))))
 492             (when (or in-defun-p
 493                       in-lambda-p
 494                       in-let-p
 495                       in-let*-p)
 496               (setq scope-stack (cons (context-coloring-make-scope
 497                                        (context-coloring-ppss-depth ppss)
 498                                        (1+ (context-coloring-scope-get-level
 499                                             (car scope-stack))))
 500                                       scope-stack)))
 501             ;; TODO: Probably redundant and wasteful.
 502             (context-coloring-colorize-region token-pos
 503                                               (scan-sexps token-pos 1)
 504                                               (context-coloring-scope-get-level
 505                                                (car scope-stack)))
 506             (cond
 507              ((or in-defun-p
 508                   in-lambda-p)
 509               (goto-char child-0-end)
 510               (when in-defun-p
 511                 ;; Look for a function name.
 512                 (context-coloring-forward-sws)
 513                 (setq child-1-pos (point))
 514                 (setq child-1-syntax (syntax-after child-1-pos))
 515                 (setq child-1-syntax-code (logand #xFFFF (car child-1-syntax)))
 516                 (cond
 517                  ((context-coloring-emacs-lisp-identifier-syntax-p child-1-syntax-code)
 518                   (setq child-1-end (scan-sexps child-1-pos 1))
 519                   ;; Defuns are global, so use level 0.
 520                   (context-coloring-colorize-region child-1-pos child-1-end 0)
 521                   (goto-char child-1-end))))
 522               ;; Look for an arglist.
 523               (context-coloring-forward-sws)
 524               (when (context-coloring-at-open-parenthesis-p)
 525                 ;; (Actually it should be `child-1-end' for `lambda'.)
 526                 (setq child-2-end (context-coloring-forward-sexp-position))
 527                 (setq defun-arglist (read (buffer-substring-no-properties
 528                                            (point)
 529                                            child-2-end)))
 530                 (while defun-arglist
 531                   (setq defun-arg (car defun-arglist))
 532                   (when (and (symbolp defun-arg)
 533                              (string-match-p
 534                               context-coloring-arglist-arg-regexp
 535                               (symbol-name defun-arg)))
 536                     (context-coloring-scope-add-variable
 537                      (car scope-stack)
 538                      defun-arg))
 539                   (setq defun-arglist (cdr defun-arglist)))
 540                 (goto-char child-2-end))
 541               ;; Cleanup.
 542               (setq in-defun-p nil)
 543               (setq in-lambda-p nil))
 544              ((or in-let-p
 545                   in-let*-p)
 546               (goto-char child-0-end)
 547               ;; Look for bindings.
 548               (context-coloring-forward-sws)
 549               (setq child-1-pos (point))
 550               (setq child-1-syntax (syntax-after child-1-pos))
 551               (setq child-1-syntax-code (logand #xFFFF (car child-1-syntax)))
 552               (when (= 4 child-1-syntax-code)
 553                 (setq child-1-end (context-coloring-forward-sexp-position))
 554                 (setq let-varlist (read (buffer-substring-no-properties
 555                                          (point)
 556                                          child-1-end)))
 557                 (while let-varlist
 558                   (setq let-var (car let-varlist))
 559                   (cond
 560                    ((symbolp let-var)
 561                     (context-coloring-scope-add-variable
 562                      (car scope-stack)
 563                      let-var))
 564                    ((listp let-var)
 565                     (context-coloring-scope-add-variable
 566                      (car scope-stack)
 567                      (car let-var))
 568                     ;; TODO: Recurse or use stack to eval var value.
 569                     ))
 570                   (setq let-varlist (cdr let-varlist)))
 571                 (goto-char child-1-end))
 572               ;; Cleanup.
 573               (setq in-let-p nil)
 574               (setq in-let*-p nil))
 575              (t
 576               (goto-char (cond
 577                           ;; If there was a word, continue parsing after it.
 578                           (one-word-found-p
 579                            (1+ child-0-end))
 580                           (t
 581                            (1+ token-pos))))))
 582             ;; Cleanup.
 583             (setq one-word-found-p nil))
 584
 585            ((context-coloring-emacs-lisp-identifier-syntax-p token-syntax-code)
 586             (setq variable-end (context-coloring-forward-sexp-position))
 587             (setq variable-string (buffer-substring-no-properties
 588                                    token-pos
 589                                    variable-end))
 590             (cond
 591              ;; Ignore constants such as numbers, keywords, t, nil.  These can't
 592              ;; be rebound, so they should be treated like syntax.
 593              ((string-match-p context-coloring-unbindable-constant-regexp variable-string))
 594              ((keywordp (read variable-string)))
 595              (t
 596               (setq variable (intern variable-string))
 597               (setq variable-scope-level
 598                     (context-coloring-get-variable-level scope-stack variable))
 599               (when (/= variable-scope-level (context-coloring-scope-get-level
 600                                               (car scope-stack)))
 601                 (context-coloring-colorize-region
 602                  token-pos
 603                  variable-end
 604                  variable-scope-level))))
 605             (goto-char variable-end))
 606
 607            ((context-coloring-close-parenthesis-p token-syntax-code)
 608             (forward-char)
 609             (setq ppss (parse-partial-sexp last-ppss-pos (point) nil nil ppss))
 610             (setq last-ppss-pos (point))
 611             (when (= (context-coloring-ppss-depth ppss)
 612                      (context-coloring-scope-get-depth (car scope-stack)))
 613               (setq scope-stack (cdr scope-stack))))
 614
 615            ))))
 616     (context-coloring-maybe-colorize-comments-and-strings)))
 617
 618
 619 ;;; Shell command scopification / colorization
 620
 621 (defun context-coloring-apply-tokens (tokens)
 622   "Process a vector of TOKENS to apply context-based coloring to
 623 the current buffer.  Tokens are 3 integers: start, end, level.
 624 The vector is flat, with a new token occurring after every 3rd
 625 element."
 626   (with-silent-modifications
 627     (let ((i 0)
 628           (len (length tokens)))
 629       (while (< i len)
 630         (context-coloring-colorize-region
 631          (elt tokens i)
 632          (elt tokens (+ i 1))
 633          (elt tokens (+ i 2)))
 634         (setq i (+ i 3))))
 635     (context-coloring-maybe-colorize-comments-and-strings)))
 636
 637 (defun context-coloring-parse-array (array)
 638   "Parse ARRAY as a flat JSON array of numbers."
 639   (let ((braceless (substring (context-coloring-trim array) 1 -1)))
 640     (cond
 641      ((> (length braceless) 0)
 642       (vconcat
 643        (mapcar 'string-to-number (split-string braceless ","))))
 644      (t
 645       (vector)))))
 646
 647 (defvar-local context-coloring-scopifier-process nil
 648   "The single scopifier process that can be running.")
 649
 650 (defun context-coloring-kill-scopifier ()
 651   "Kill the currently-running scopifier process."
 652   (when (not (null context-coloring-scopifier-process))
 653     (delete-process context-coloring-scopifier-process)
 654     (setq context-coloring-scopifier-process nil)))
 655
 656 (defun context-coloring-scopify-shell-command (command callback)
 657   "Invoke a scopifier via COMMAND, read its response
 658 asynchronously and invoke CALLBACK with its output."
 659
 660   ;; Prior running tokenization is implicitly obsolete if this function is
 661   ;; called.
 662   (context-coloring-kill-scopifier)
 663
 664   ;; Start the process.
 665   (setq context-coloring-scopifier-process
 666         (start-process-shell-command "scopifier" nil command))
 667
 668   (let ((output ""))
 669
 670     ;; The process may produce output in multiple chunks.  This filter
 671     ;; accumulates the chunks into a message.
 672     (set-process-filter
 673      context-coloring-scopifier-process
 674      (lambda (_process chunk)
 675        (setq output (concat output chunk))))
 676
 677     ;; When the process's message is complete, this sentinel parses it as JSON
 678     ;; and applies the tokens to the buffer.
 679     (set-process-sentinel
 680      context-coloring-scopifier-process
 681      (lambda (_process event)
 682        (when (equal "finished\n" event)
 683          (funcall callback output))))))
 684
 685 (defun context-coloring-send-buffer-to-scopifier ()
 686   "Give the scopifier process its input so it can begin
 687 scopifying."
 688   (process-send-region
 689    context-coloring-scopifier-process
 690    (point-min) (point-max))
 691   (process-send-eof
 692    context-coloring-scopifier-process))
 693
 694 (defun context-coloring-scopify-and-colorize (command &optional callback)
 695   "Invoke a scopifier via COMMAND with the current buffer's contents,
 696 read the scopifier's response asynchronously and apply a parsed
 697 list of tokens to `context-coloring-apply-tokens'.
 698
 699 Invoke CALLBACK when complete."
 700   (let ((buffer context-coloring-buffer))
 701     (context-coloring-scopify-shell-command
 702      command
 703      (lambda (output)
 704        (let ((tokens (context-coloring-parse-array output)))
 705          (with-current-buffer buffer
 706            (context-coloring-apply-tokens tokens))
 707          (setq context-coloring-scopifier-process nil)
 708          (when callback (funcall callback))))))
 709   (context-coloring-send-buffer-to-scopifier))
 710
 711
 712 ;;; Dispatch
 713
 714 (defvar context-coloring-dispatch-hash-table (make-hash-table :test 'eq)
 715   "Map dispatch strategy names to their corresponding property
 716   lists, which contain details about the strategies.")
 717
 718 (defvar context-coloring-mode-hash-table (make-hash-table :test 'eq)
 719   "Map major mode names to dispatch property lists.")
 720
 721 (defun context-coloring-define-dispatch (symbol &rest properties)
 722   "Define a new dispatch named SYMBOL with PROPERTIES.
 723
 724 A \"dispatch\" is a property list describing a strategy for
 725 coloring a buffer.  There are three possible strategies: Parse
 726 and color in a single function (`:colorizer'), parse in a
 727 function that returns scope data (`:scopifier'), or parse with a
 728 shell command that returns scope data (`:command').  In the
 729 latter two cases, the scope data will be used to automatically
 730 color the buffer.
 731
 732 PROPERTIES must include `:modes' and one of `:colorizer',
 733 `:scopifier' or `:command'.
 734
 735 `:modes' - List of major modes this dispatch is valid for.
 736
 737 `:colorizer' - Symbol referring to a function that parses and
 738 colors the buffer.
 739
 740 `:scopifier' - Symbol referring to a function that parses the
 741 buffer a returns a flat vector of start, end and level data.
 742
 743 `:executable' - Optional name of an executable required by
 744 `:command'.
 745
 746 `:command' - Shell command to execute with the current buffer
 747 sent via stdin, and with a flat JSON array of start, end and
 748 level data returned via stdout.
 749
 750 `:version' - Minimum required version that should be printed when
 751 executing `:command' with a \"--version\" flag.  The version
 752 should be numeric, e.g. \"2\", \"19700101\", \"1.2.3\",
 753 \"v1.2.3\" etc.
 754
 755 `:setup' - Arbitrary code to set up this dispatch when
 756 `context-coloring-mode' is enabled.
 757
 758 `:teardown' - Arbitrary code to tear down this dispatch when
 759 `context-coloring-mode' is disabled."
 760   (let ((modes (plist-get properties :modes))
 761         (colorizer (plist-get properties :colorizer))
 762         (scopifier (plist-get properties :scopifier))
 763         (command (plist-get properties :command)))
 764     (when (null modes)
 765       (error "No mode defined for dispatch"))
 766     (when (not (or colorizer
 767                    scopifier
 768                    command))
 769       (error "No colorizer, scopifier or command defined for dispatch"))
 770     (puthash symbol properties context-coloring-dispatch-hash-table)
 771     (dolist (mode modes)
 772       (when (null (gethash mode context-coloring-mode-hash-table))
 773         (puthash mode properties context-coloring-mode-hash-table)))))
 774
 775 (context-coloring-define-dispatch
 776  'javascript-node
 777  :modes '(js-mode js3-mode)
 778  :executable "scopifier"
 779  :command "scopifier"
 780  :version "v1.1.1")
 781
 782 (context-coloring-define-dispatch
 783  'javascript-js2
 784  :modes '(js2-mode)
 785  :colorizer 'context-coloring-js2-colorize
 786  :setup
 787  (lambda ()
 788    (add-hook 'js2-post-parse-callbacks 'context-coloring-colorize nil t))
 789  :teardown
 790  (lambda ()
 791    (remove-hook 'js2-post-parse-callbacks 'context-coloring-colorize t)))
 792
 793 (context-coloring-define-dispatch
 794  'emacs-lisp
 795  :modes '(emacs-lisp-mode)
 796  :colorizer 'context-coloring-emacs-lisp-colorize)
 797
 798 (defun context-coloring-dispatch (&optional callback)
 799   "Determine the optimal track for scopification / coloring of
 800 the current buffer, then execute it.
 801
 802 Invoke CALLBACK when complete.  It is invoked synchronously for
 803 elisp tracks, and asynchronously for shell command tracks."
 804   (let ((dispatch (gethash major-mode context-coloring-mode-hash-table))
 805         colorizer
 806         scopifier
 807         command)
 808     (cond
 809      ((setq colorizer (plist-get dispatch :colorizer))
 810       (funcall colorizer)
 811       (when callback (funcall callback)))
 812      ((setq scopifier (plist-get dispatch :scopifier))
 813       (context-coloring-apply-tokens (funcall scopifier))
 814       (when callback (funcall callback)))
 815      ((setq command (plist-get dispatch :command))
 816       (context-coloring-scopify-and-colorize command callback)))))
 817
 818
 819 ;;; Colorization
 820
 821 (defvar context-coloring-colorize-hook nil
 822   "Hooks to run after coloring a buffer.")
 823
 824 (defun context-coloring-colorize (&optional callback)
 825   "Color the current buffer by function context.
 826
 827 Invoke CALLBACK when complete; see `context-coloring-dispatch'."
 828   (interactive)
 829   (context-coloring-dispatch
 830    (lambda ()
 831      (when callback (funcall callback))
 832      (run-hooks 'context-coloring-colorize-hook))))
 833
 834 (defvar-local context-coloring-changed nil
 835   "Indication that the buffer has changed recently, which implies
 836 that it should be colored again by
 837 `context-coloring-colorize-idle-timer' if that timer is being
 838 used.")
 839
 840 (defun context-coloring-change-function (_start _end _length)
 841   "Register a change so that a buffer can be colorized soon."
 842   ;; Tokenization is obsolete if there was a change.
 843   (context-coloring-kill-scopifier)
 844   (setq context-coloring-changed t))
 845
 846 (defun context-coloring-maybe-colorize ()
 847   "Colorize the current buffer if it has changed."
 848   (when (and (eq context-coloring-buffer (window-buffer (selected-window)))
 849              context-coloring-changed)
 850     (setq context-coloring-changed nil)
 851     (context-coloring-colorize)))
 852
 853
 854 ;;; Versioning
 855
 856 (defun context-coloring-parse-version (string)
 857   "Extract segments of a version STRING into a list.  \"v1.0.0\"
 858 produces (1 0 0), \"19700101\" produces (19700101), etc."
 859   (let (version)
 860     (while (string-match "[0-9]+" string)
 861       (setq version (append version
 862                             (list (string-to-number (match-string 0 string)))))
 863       (setq string (substring string (match-end 0))))
 864     version))
 865
 866 (defun context-coloring-check-version (expected actual)
 867   "Check that version EXPECTED is less than or equal to ACTUAL."
 868   (let ((expected (context-coloring-parse-version expected))
 869         (actual (context-coloring-parse-version actual))
 870         (continue t)
 871         (acceptable t))
 872     (while (and continue expected)
 873       (let ((an-expected (car expected))
 874             (an-actual (car actual)))
 875         (cond
 876          ((> an-actual an-expected)
 877           (setq acceptable t)
 878           (setq continue nil))
 879          ((< an-actual an-expected)
 880           (setq acceptable nil)
 881           (setq continue nil))))
 882       (setq expected (cdr expected))
 883       (setq actual (cdr actual)))
 884     acceptable))
 885
 886 (defvar context-coloring-check-scopifier-version-hook nil
 887   "Hooks to run after checking the scopifier version.")
 888
 889 (defun context-coloring-check-scopifier-version (&optional callback)
 890   "Asynchronously invoke CALLBACK with a predicate indicating
 891 whether the current scopifier version satisfies the minimum
 892 version number required for the current major mode."
 893   (let ((dispatch (gethash major-mode context-coloring-mode-hash-table)))
 894     (when dispatch
 895       (let ((version (plist-get dispatch :version))
 896             (command (plist-get dispatch :command)))
 897         (context-coloring-scopify-shell-command
 898          (context-coloring-join (list command "--version") " ")
 899          (lambda (output)
 900            (if (context-coloring-check-version version output)
 901                (progn
 902                  (when callback (funcall callback t)))
 903              (when callback (funcall callback nil)))
 904            (run-hooks 'context-coloring-check-scopifier-version-hook)))))))
 905
 906
 907 ;;; Themes
 908
 909 (defvar context-coloring-theme-hash-table (make-hash-table :test 'eq)
 910   "Map theme names to theme properties.")
 911
 912 (defun context-coloring-theme-p (theme)
 913   "Return t if THEME is defined, nil otherwise."
 914   (and (gethash theme context-coloring-theme-hash-table)))
 915
 916 (defconst context-coloring-level-face-regexp
 917   "context-coloring-level-\\([[:digit:]]+\\)-face"
 918   "Extract a level from a face.")
 919
 920 (defvar context-coloring-originally-set-theme-hash-table
 921   (make-hash-table :test 'eq)
 922   "Cache custom themes who originally set their own
 923   `context-coloring-level-N-face' faces.")
 924
 925 (defun context-coloring-theme-originally-set-p (theme)
 926   "Return t if there is a `context-coloring-level-N-face'
 927 originally set for THEME, nil otherwise."
 928   (let (originally-set)
 929     (cond
 930      ;; `setq' might return a non-nil value for the sake of this `cond'.
 931      ((setq
 932        originally-set
 933        (gethash
 934         theme
 935         context-coloring-originally-set-theme-hash-table))
 936       (eq originally-set 'yes))
 937      (t
 938       (let* ((settings (get theme 'theme-settings))
 939              (tail settings)
 940              found)
 941         (while (and tail (not found))
 942           (and (eq (nth 0 (car tail)) 'theme-face)
 943                (string-match
 944                 context-coloring-level-face-regexp
 945                 (symbol-name (nth 1 (car tail))))
 946                (setq found t))
 947           (setq tail (cdr tail)))
 948         found)))))
 949
 950 (defun context-coloring-cache-originally-set (theme originally-set)
 951   "Remember if THEME had colors originally set for it.  If
 952 ORIGINALLY-SET is non-nil, it did, otherwise it didn't."
 953   ;; Caching whether a theme was originally set is kind of dirty, but we have to
 954   ;; do it to remember the past state of the theme.  There are probably some
 955   ;; edge cases where caching will be an issue, but they are probably rare.
 956   (puthash
 957    theme
 958    (if originally-set 'yes 'no)
 959    context-coloring-originally-set-theme-hash-table))
 960
 961 (defun context-coloring-warn-theme-originally-set (theme)
 962   "Warn the user that the colors for THEME are already originally
 963 set."
 964   (warn "Context coloring colors for theme `%s' are already defined" theme))
 965
 966 (defun context-coloring-theme-highest-level (theme)
 967   "Return the highest level N of a face like
 968 `context-coloring-level-N-face' set for THEME, or `-1' if there
 969 is none."
 970   (let* ((settings (get theme 'theme-settings))
 971          (tail settings)
 972          face-string
 973          number
 974          (found -1))
 975     (while tail
 976       (and (eq (nth 0 (car tail)) 'theme-face)
 977            (setq face-string (symbol-name (nth 1 (car tail))))
 978            (string-match
 979             context-coloring-level-face-regexp
 980             face-string)
 981            (setq number (string-to-number
 982                          (substring face-string
 983                                     (match-beginning 1)
 984                                     (match-end 1))))
 985            (> number found)
 986            (setq found number))
 987       (setq tail (cdr tail)))
 988     found))
 989
 990 (defun context-coloring-apply-theme (theme)
 991   "Apply THEME's properties to its respective custom theme,
 992 which must already exist and which *should* already be enabled."
 993   (let* ((properties (gethash theme context-coloring-theme-hash-table))
 994          (colors (plist-get properties :colors))
 995          (level -1))
 996     ;; Only clobber when we have to.
 997     (when (custom-theme-enabled-p theme)
 998       (setq context-coloring-maximum-face (- (length colors) 1)))
 999     (apply
1000      'custom-theme-set-faces
1001      theme
1002      (mapcar
1003       (lambda (color)
1004         (setq level (+ level 1))
1005         `(,(context-coloring-level-face level) ((t (:foreground ,color)))))
1006       colors))))
1007
1008 (defun context-coloring-define-theme (theme &rest properties)
1009   "Define a context theme named THEME for coloring scope levels.
1010
1011 PROPERTIES is a property list specifiying the following details:
1012
1013 `:aliases': List of symbols of other custom themes that these
1014 colors are applicable to.
1015
1016 `:colors': List of colors that this context theme uses.
1017
1018 `:override': If non-nil, this context theme is intentionally
1019 overriding colors set by a custom theme.  Don't set this non-nil
1020 unless there is a custom theme you want to use which sets
1021 `context-coloring-level-N-face' faces that you want to replace.
1022
1023 `:recede': If non-nil, this context theme should not apply its
1024 colors if a custom theme already sets
1025 `context-coloring-level-N-face' faces.  This option is
1026 optimistic; set this non-nil if you would rather confer the duty
1027 of picking colors to a custom theme author (if / when he ever
1028 gets around to it).
1029
1030 By default, context themes will always override custom themes,
1031 even if those custom themes set `context-coloring-level-N-face'
1032 faces.  If a context theme does override a custom theme, a
1033 warning will be raised, at which point you may want to enable the
1034 `:override' option, or just delete your context theme and opt to
1035 use your custom theme's author's colors instead.
1036
1037 Context themes only work for the custom theme with the highest
1038 precedence, i.e. the car of `custom-enabled-themes'."
1039   (let ((aliases (plist-get properties :aliases))
1040         (override (plist-get properties :override))
1041         (recede (plist-get properties :recede)))
1042     (dolist (name (append `(,theme) aliases))
1043       (puthash name properties context-coloring-theme-hash-table)
1044       (when (custom-theme-p name)
1045         (let ((originally-set (context-coloring-theme-originally-set-p name)))
1046           (context-coloring-cache-originally-set name originally-set)
1047           ;; In the particular case when you innocently define colors that a
1048           ;; custom theme originally set, warn.  Arguably this only has to be
1049           ;; done at enable time, but it is probably more useful to do it at
1050           ;; definition time for prompter feedback.
1051           (when (and originally-set
1052                      (not recede)
1053                      (not override))
1054             (context-coloring-warn-theme-originally-set name))
1055           ;; Set (or overwrite) colors.
1056           (when (not (and originally-set
1057                           recede))
1058             (context-coloring-apply-theme name)))))))
1059
1060 (defun context-coloring-enable-theme (theme)
1061   "Apply THEME if its colors are not already set, else just set
1062 `context-coloring-maximum-face' to the correct value for THEME."
1063   (let* ((properties (gethash theme context-coloring-theme-hash-table))
1064          (recede (plist-get properties :recede))
1065          (override (plist-get properties :override)))
1066     (cond
1067      (recede
1068       (let ((highest-level (context-coloring-theme-highest-level theme)))
1069         (cond
1070          ;; This can be true whether originally set by a custom theme or by a
1071          ;; context theme.
1072          ((> highest-level -1)
1073           (setq context-coloring-maximum-face highest-level))
1074          ;; It is possible that the corresponding custom theme did not exist at
1075          ;; the time of defining this context theme, and in that case the above
1076          ;; condition proves the custom theme did not originally set any faces,
1077          ;; so we have license to apply the context theme for the first time
1078          ;; here.
1079          (t
1080           (context-coloring-apply-theme theme)))))
1081      (t
1082       (let ((originally-set (context-coloring-theme-originally-set-p theme)))
1083         ;; Cache now in case the context theme was defined after the custom
1084         ;; theme.
1085         (context-coloring-cache-originally-set theme originally-set)
1086         (when (and originally-set
1087                    (not override))
1088           (context-coloring-warn-theme-originally-set theme))
1089         (context-coloring-apply-theme theme))))))
1090
1091 (defadvice enable-theme (after context-coloring-enable-theme (theme) activate)
1092   "Enable colors for context themes just-in-time."
1093   (when (and (not (eq theme 'user)) ; Called internally by `enable-theme'.
1094              (custom-theme-p theme) ; Guard against non-existent themes.
1095              (context-coloring-theme-p theme))
1096     (when (= (length custom-enabled-themes) 1)
1097       ;; Cache because we can't reliably figure it out in reverse.
1098       (setq context-coloring-original-maximum-face
1099             context-coloring-maximum-face))
1100     (context-coloring-enable-theme theme)))
1101
1102 (defadvice disable-theme (after context-coloring-disable-theme (theme) activate)
1103   "Update `context-coloring-maximum-face'."
1104   (when (custom-theme-p theme) ; Guard against non-existent themes.
1105     (let ((enabled-theme (car custom-enabled-themes)))
1106       (if (context-coloring-theme-p enabled-theme)
1107           (progn
1108             (context-coloring-enable-theme enabled-theme))
1109         ;; Assume we are back to no theme; act as if nothing ever happened.
1110         ;; This is still prone to intervention, but rather extraordinarily.
1111         (setq context-coloring-maximum-face
1112               context-coloring-original-maximum-face)))))
1113
1114 (context-coloring-define-theme
1115  'ample
1116  :recede t
1117  :colors '("#bdbdb3"
1118            "#baba36"
1119            "#6aaf50"
1120            "#5180b3"
1121            "#ab75c3"
1122            "#cd7542"
1123            "#df9522"
1124            "#454545"))
1125
1126 (context-coloring-define-theme
1127  'anti-zenburn
1128  :recede t
1129  :colors '("#232333"
1130            "#6c1f1c"
1131            "#401440"
1132            "#0f2050"
1133            "#205070"
1134            "#336c6c"
1135            "#23733c"
1136            "#6b400c"
1137            "#603a60"
1138            "#2f4070"
1139            "#235c5c"))
1140
1141 (context-coloring-define-theme
1142  'grandshell
1143  :recede t
1144  :colors '("#bebebe"
1145            "#5af2ee"
1146            "#b2baf6"
1147            "#f09fff"
1148            "#efc334"
1149            "#f6df92"
1150            "#acfb5a"
1151            "#888888"))
1152
1153 (context-coloring-define-theme
1154  'leuven
1155  :recede t
1156  :colors '("#333333"
1157            "#0000ff"
1158            "#6434a3"
1159            "#ba36a5"
1160            "#d0372d"
1161            "#036a07"
1162            "#006699"
1163            "#006fe0"
1164            "#808080"))
1165
1166 (context-coloring-define-theme
1167  'monokai
1168  :recede t
1169  :colors '("#f8f8f2"
1170            "#66d9ef"
1171            "#a1efe4"
1172            "#a6e22e"
1173            "#e6db74"
1174            "#fd971f"
1175            "#f92672"
1176            "#fd5ff0"
1177            "#ae81ff"))
1178
1179 (context-coloring-define-theme
1180  'solarized
1181  :recede t
1182  :aliases '(solarized-light
1183             solarized-dark
1184             sanityinc-solarized-light
1185             sanityinc-solarized-dark)
1186  :colors '("#839496"
1187            "#268bd2"
1188            "#2aa198"
1189            "#859900"
1190            "#b58900"
1191            "#cb4b16"
1192            "#dc322f"
1193            "#d33682"
1194            "#6c71c4"
1195            "#69b7f0"
1196            "#69cabf"
1197            "#b4c342"
1198            "#deb542"
1199            "#f2804f"
1200            "#ff6e64"
1201            "#f771ac"
1202            "#9ea0e5"))
1203
1204 (context-coloring-define-theme
1205  'spacegray
1206  :recede t
1207  :colors '("#ffffff"
1208            "#89aaeb"
1209            "#c189eb"
1210            "#bf616a"
1211            "#dca432"
1212            "#ebcb8b"
1213            "#b4eb89"
1214            "#89ebca"))
1215
1216 (context-coloring-define-theme
1217  'tango
1218  :recede t
1219  :colors '("#2e3436"
1220            "#346604"
1221            "#204a87"
1222            "#5c3566"
1223            "#a40000"
1224            "#b35000"
1225            "#c4a000"
1226            "#8ae234"
1227            "#8cc4ff"
1228            "#ad7fa8"
1229            "#ef2929"
1230            "#fcaf3e"
1231            "#fce94f"))
1232
1233 (context-coloring-define-theme
1234  'zenburn
1235  :recede t
1236  :colors '("#dcdccc"
1237            "#93e0e3"
1238            "#bfebbf"
1239            "#f0dfaf"
1240            "#dfaf8f"
1241            "#cc9393"
1242            "#dc8cc3"
1243            "#94bff3"
1244            "#9fc59f"
1245            "#d0bf8f"
1246            "#dca3a3"))
1247
1248
1249 ;;; Minor mode
1250
1251 (defvar-local context-coloring-colorize-idle-timer nil
1252   "The currently-running idle timer.")
1253
1254 (defcustom context-coloring-delay 0.25
1255   "Delay between a buffer update and colorization.
1256
1257 Increase this if your machine is high-performing.  Decrease it if
1258 it ain't.
1259
1260 Supported modes: `js-mode', `js3-mode'"
1261   :group 'context-coloring)
1262
1263 (defun context-coloring-setup-idle-change-detection ()
1264   "Setup idle change detection."
1265   (add-hook
1266    'after-change-functions 'context-coloring-change-function nil t)
1267   (setq context-coloring-colorize-idle-timer
1268         (run-with-idle-timer
1269          context-coloring-delay
1270          t
1271          'context-coloring-maybe-colorize)))
1272
1273 ;;;###autoload
1274 (define-minor-mode context-coloring-mode
1275   "Context-based code coloring, inspired by Douglas Crockford."
1276   nil " Context" nil
1277   (if (not context-coloring-mode)
1278       (progn
1279         (context-coloring-kill-scopifier)
1280         (when context-coloring-colorize-idle-timer
1281           (cancel-timer context-coloring-colorize-idle-timer))
1282         (let ((dispatch (gethash major-mode context-coloring-mode-hash-table)))
1283           (when dispatch
1284             (let ((command (plist-get dispatch :command))
1285                   (teardown (plist-get dispatch :teardown)))
1286               (when command
1287                 (remove-hook
1288                  'after-change-functions 'context-coloring-change-function t))
1289               (when teardown
1290                 (funcall teardown)))))
1291         (font-lock-mode)
1292         (jit-lock-mode t))
1293
1294     ;; Remember this buffer.  This value should not be dynamically-bound.
1295     (setq context-coloring-buffer (current-buffer))
1296
1297     ;; Font lock is incompatible with this mode; the converse is also true.
1298     (font-lock-mode 0)
1299     (jit-lock-mode nil)
1300
1301     ;; Safely change the valye of this function as necessary.
1302     (make-local-variable 'font-lock-syntactic-face-function)
1303
1304     (let ((dispatch (gethash major-mode context-coloring-mode-hash-table)))
1305       (if dispatch
1306           (progn
1307             (let ((command (plist-get dispatch :command))
1308                   (version (plist-get dispatch :version))
1309                   (executable (plist-get dispatch :executable))
1310                   (setup (plist-get dispatch :setup))
1311                   (colorize-initially-p t))
1312               (when command
1313                 ;; Shell commands recolor on change, idly.
1314                 (cond
1315                  ((and executable
1316                        (null (executable-find executable)))
1317                   (message "Executable \"%s\" not found" executable)
1318                   (setq colorize-initially-p nil))
1319                  (version
1320                   (context-coloring-check-scopifier-version
1321                    (lambda (sufficient-p)
1322                      (if sufficient-p
1323                          (progn
1324                            (context-coloring-setup-idle-change-detection)
1325                            (context-coloring-colorize))
1326                        (message "Update to the minimum version of \"%s\" (%s)"
1327                                 executable version))))
1328                   (setq colorize-initially-p nil))
1329                  (t
1330                   (context-coloring-setup-idle-change-detection))))
1331               (when setup
1332                 (funcall setup))
1333               ;; Colorize once initially.
1334               (when colorize-initially-p
1335                 (context-coloring-colorize))))
1336         (when (null dispatch)
1337           (message "Context coloring is not available for this major mode"))))))
1338
1339 (provide 'context-coloring)
1340
1341 ;;; context-coloring.el ends here