[elpa] externals/auto-correct 9147742 01/11: Added auto-correct package

[Stefan Monnier]

branch: externals/auto-correct
commit 91477427caee2c030dc93552887a01cc1c9f3fd4
Author: Ian Dunn <dunni@gnu.org>
Commit: Ian Dunn <dunni@gnu.org>

    Added auto-correct package
    
    Single-file package to automatically make corrections found by packages 
such as
    Ispell and flyspell.
    
    * packages/auto-correct/auto-correct.el: Added.
---
 auto-correct.el | 369 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 369 insertions(+)

diff --git a/auto-correct.el b/auto-correct.el
new file mode 100644
index 0000000..42f84de
--- /dev/null
+++ b/auto-correct.el
@@ -0,0 +1,369 @@
+;;; auto-correct.el --- Remembers and automatically fixes past corrections -*- 
lexical-binding: t; -*-
+
+;; Copyright (C) 2017 Free Software Foundation, Inc.
+
+;; Author: Ian Dunn <dunni@gnu.org>
+;; Maintainer: Ian Dunn <dunni@gnu.org>
+;; Keywords: editing
+;; Version: 1.0
+
+;; This file is part of GNU Emacs.
+
+;; This program is free software: you can redistribute it and/or modify
+;; it under the terms of the GNU General Public License as published by
+;; the Free Software Foundation, either version 3 of the License, or
+;; (at your option) any later version.
+
+;; This program is distributed in the hope that it will be useful,
+;; but WITHOUT ANY WARRANTY; without even the implied warranty of
+;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+;; GNU General Public License for more details.
+
+;; You should have received a copy of the GNU General Public License
+;; along with this program.  If not, see <http://www.gnu.org/licenses/>.
+
+;;; Commentary:
+
+;; To enable, use:
+
+;; M-x `auto-correct-mode'
+
+;; After that, any future corrections made with flyspell or Ispell (or any 
other
+;; supported package) will be automatically corrected for you as you type.
+
+;; For example, if you type "befroe" and fixed it with `ispell-word',
+;; `auto-correct-mode' will change "befroe" to "before" every time you type it
+;; from then on.
+
+;; Corrections are only made when `auto-correct-mode' is enabled.  Expansion is
+;; case-insensitive, so trying to fix alice as Alice won't work.
+
+;; For more fine-grained control over when corrections are made, set the
+;; buffer-local variable `auto-correct-predicate'.
+
+;; Behind the scenes, auto-correct uses an abbrev table, so in order to clean
+;; out or modify any fixes auto-correct has learned, use `list-abbrevs'.  This
+;; also means that fixes are saved between Emacs sessions along with the abbrev
+;; tables.
+
+;; Ispell and flyspell are the only two packages that auto-correct supports out
+;; of the box, but it's possible to add support for any package that corrects
+;; text:
+
+;; 1. Create a function that calls `auto-correct--add-or-update-correction' 
with
+;; the old text and the corrected text from your package.
+
+;; 2. Write two functions: an activation function and a deactivation function.
+;; These will be called by `auto-correct-mode' to activate and deactivate
+;; support.
+
+;; 3. Call `auto-correct--add-support' with your activation and deactivation
+;; functions.
+
+;; 4. You're done.
+
+;;; Code:
+
+(eval-when-compile (require 'subr-x))
+(require 'thingatpt)
+
+(defgroup auto-correct nil
+  "Auto correction support."
+  :prefix "auto-correct-"
+  :group 'editing)
+
+;; Core Functionality
+
+(defvar-local auto-correct-predicate nil
+  "Predicate to check whether automatic corrections should be made.
+
+This should be a function of no arguments that returns non-nil if
+auto-correct should operate on the current text.")
+
+(defun auto-correct-expand-p ()
+  "Return non-nil if auto-correct should operate on the current point.
+
+To customize this behavior, set `auto-correct-predicate'."
+  (when auto-correct-predicate (funcall auto-correct-predicate)))
+
+(define-abbrev-table 'auto-correct-abbrev-table nil
+  "Abbrev table where automatic corrections are stored."
+  :enable-function #'auto-correct-expand-p)
+
+(defun auto-correct--get-abbrev-table (local)
+  "Get the abbrev table to use with auto-correct.
+
+If LOCAL is non-nil, use the local table if it exists.
+Otherwise, use auto-correct's abbrev table."
+  (if local
+      (or local-abbrev-table auto-correct-abbrev-table)
+    auto-correct-abbrev-table))
+
+(defun auto-correct--add-or-update-correction (before after &optional local)
+  "Add or update a correction into auto-correct's table.
+
+BEFORE is the misspelled word, and AFTER is the correct spelling.
+
+Optional argument LOCAL determines whether to make the correction
+locally.  If nil, the correction will be made whenever
+`auto-correct-mode' is enabled."
+  (let ((table (auto-correct--get-abbrev-table local))
+        (bef (downcase before))
+        (aft (downcase after)))
+    (define-abbrev table bef aft nil :count 1)
+    ;; Save the abbrevs.
+    (write-abbrev-file)
+    (message "\"%s\" now expands to \"%s\"" bef aft)))
+
+;; Extension Support
+
+(defvar auto-correct-activate-functions nil
+  "Functions to run to activate auto-correct support in various packages.
+
+These are called by `auto-correct-mode' when it is enabled.")
+
+(defvar auto-correct-deactivate-functions nil
+  "Functions to run to deactivate auto-correct support in various packages.
+
+These are called by `auto-correct-mode' when it is disabled.")
+
+;; The mode
+
+;;;###autoload
+(define-minor-mode auto-correct-mode
+  "Activate automatic corrections.
+
+Auto correct expansions will only work when this mode is enabled,
+but auto-correct can be trained with `auto-correct-fix-and-add'
+even if this mode is disabled.
+
+When this mode is enabled, corrections made with flyspell and
+Ispell will be made automatically after fixing them once.
+
+In order to add corrections to the auto-correct abbrev table in
+flyspell (and thus have them corrected later), set
+`flyspell-use-global-abbrev-table-p' to non-nil.
+
+In order to set corrections as local using Ispell, use
+the command `auto-correct-toggle-ispell-local'.
+
+\\{auto-correct-mode-map}"
+  :group 'auto-correct
+  :global t
+  :init-value nil
+  :lighter " Auto-Correct"
+  (if auto-correct-mode
+      (run-hooks 'auto-correct-activate-functions)
+    (run-hooks 'auto-correct-deactivate-functions)))
+
+;; Only enable the abbrev list when auto-correct-mode is active.
+(add-to-list 'abbrev-minor-mode-table-alist
+             `(auto-correct-mode ,auto-correct-abbrev-table)
+             'append
+             #'equal)
+
+(defun auto-correct--add-support (activate-fun deactivate-fun)
+  "Add auto-correct support for a spelling package.
+
+Support will be activated by ACTIVATE-FUN and deactivated by DEACTIVATE-FUN."
+  (add-hook 'auto-correct-activate-functions activate-fun)
+  (add-hook 'auto-correct-deactivate-functions deactivate-fun)
+  ;; If `auto-correct-mode' is enabled, activate this package's support.
+  (when auto-correct-mode
+    (funcall activate-fun)))
+
+(defun auto-correct--remove-support (activate-fun deactivate-fun)
+  "Remove support for a spelling package.
+
+Support will be activated by ACTIVATE-FUN and deactivated by DEACTIVATE-FUN."
+  (remove-hook 'auto-correct-activate-functions activate-fun)
+  (remove-hook 'auto-correct-deactivate-functions deactivate-fun)
+  ;; If `auto-correct-mode' is enabled, deactivate this package's support.
+  (when auto-correct-mode
+    (funcall deactivate-fun)))
+
+(defun auto-correct--handle-support (add activate-fun deactivate-fun)
+  "Helper function to add or remove auto-correct support for a package.
+
+If ADD is non-nil, add support, otherwise remove it.
+ACTIVATE-FUN and DEACTIVATE-FUN are exactly as they are in
+`auto-correct--add-support'."
+  (if add
+      (auto-correct--add-support activate-fun deactivate-fun)
+    (auto-correct--remove-support activate-fun deactivate-fun)))
+
+;; Flyspell Support
+
+(defvar flyspell-auto-correct-word)
+(defvar flyspell-use-global-abbrev-table-p)
+(defvar flyspell-insert-function)
+
+(defun auto-correct-flyspell-insert (word)
+  "Insert WORD and add it as a correction.
+
+The original (misspelled) word is drawn from the variable
+`flyspell-auto-correct-word'.
+
+When `auto-correct-mode' is enabled, this function is set as
+`flyspell-insert-function'."
+  (let ((old-word flyspell-auto-correct-word)
+        (new-word word)
+        (local (not flyspell-use-global-abbrev-table-p)))
+    (auto-correct--add-or-update-correction old-word new-word local)
+    (insert word)))
+
+(defun auto-correct--flyspell-activate ()
+  "Activate flyspell auto-correct support.
+
+Sets `flyspell-insert-function' to `auto-correct-flyspell-insert'."
+  ;; Add flyspell corrections as auto-corrections
+  (setq flyspell-insert-function 'auto-correct-flyspell-insert))
+
+(defun auto-correct--flyspell-deactivate ()
+  "Deactivate flyspell auto-correct support."
+  (setq flyspell-insert-function 'insert))
+
+(defcustom auto-correct-enable-flyspell-support t
+  "Whether to automatically correct corrections made in flyspell."
+  :group 'auto-correct
+  :type 'boolean
+  :set (lambda (sym val)
+         (set sym val)
+         (auto-correct--handle-support
+          val
+          'auto-correct--flyspell-activate
+          'auto-correct--flyspell-deactivate)))
+
+;; Ispell support
+
+(defvar ispell-following-word)
+
+(defvar auto-correct--ispell-use-local-table nil
+  "Whether to use the local table with Ispell.
+
+Toggle this interactively with `auto-correct-toggle-ispell-local'.")
+
+(defun auto-correct-toggle-ispell-local ()
+  "Toggle whether to use the local or auto-correct table for Ispell."
+  (interactive)
+  (setq auto-correct--ispell-use-local-table
+        (not auto-correct--ispell-use-local-table))
+  (message "Auto-Correct is now using the %s table"
+           (if auto-correct--ispell-use-local-table "local" "global")))
+
+(defun auto-correct--ispell-handler (ispell-result)
+  "Add ISPELL-RESULT as a correction.
+
+The original (misspelled) word is drawn from the function
+`word-at-point'.
+
+This is intended to be added as advice to `ispell-command-loop'."
+  (when-let ((word-before (word-at-point))
+             (correction ispell-result))
+    (when (and correction (consp correction))
+      ;; The correction was entered by hand.
+      (setq correction (car correction)))
+    (if (and (not (or (eq correction 0)  ;; Word was corrected from list
+                    (eq correction 'quit))) ;; Session was exited
+             (not (equal word-before correction))) ;; Word was corrected
+        (auto-correct--add-or-update-correction word-before correction
+                                          
auto-correct--ispell-use-local-table)))
+  ispell-result)
+
+(defun auto-correct--ispell-activate ()
+  "Activate Ispell auto-correct support.
+
+Adds advice to `ispell-command-loop' that adds the result as a
+correction."
+  ;; Add corrections from ispell as auto-corrections
+  (advice-add 'ispell-command-loop :filter-return
+              #'auto-correct--ispell-handler))
+
+(defun auto-correct--ispell-deactivate ()
+  "Deactivate Ispell auto-correct support."
+  (advice-remove 'ispell-command-loop #'auto-correct--ispell-handler))
+
+(defcustom auto-correct-enable-ispell-support t
+  "Whether to automatically correct corrections made in Ispell."
+  :group 'auto-correct
+  :type 'boolean
+  :set (lambda (sym val)
+         (set sym val)
+         (auto-correct--handle-support
+          val
+          'auto-correct--ispell-activate
+          'auto-correct--ispell-deactivate)))
+
+;; Standalone (piggybacks on Ispell)
+
+;;;###autoload
+(defun auto-correct-fix-and-add (local)
+  "Use `ispell-word' to fix a misspelled word at point.
+
+Once the misspelled word is fixed, auto-correct will remember the
+fix and auto-correct it from then on, so long as
+`auto-correct-mode' is enabled.
+
+With a non-nil argument LOCAL (interactively, the prefix argument),
+create a fix for the typo that will be auto-corrected for buffers
+using the current local mode.
+
+This is pointless to use when `auto-correct-mode' is enabled;
+instead, use `ispell-word' and `auto-correct-toggle-ispell-local'
+to use the local abbrev table."
+  (interactive "P")
+  (let ((auto-correct--ispell-use-local-table local))
+    (auto-correct--ispell-handler (ispell-word ispell-following-word 
'quietly))))
+
+;;;###autoload
+(defun auto-correct-scan-buffer ()
+  "Scan current buffer for misspelled words.
+
+When a misspelled word is found, offer to correct the misspelled
+word and auto-correct the typo in the future.
+
+When `auto-correct-mode' is enabled, use the `ispell' command
+instead."
+  (interactive)
+  (save-excursion
+    (goto-char (point-min))
+    ;; Stop from being prompted to save the personal dictionary after every
+    ;; change.
+    (cl-letf (((symbol-function 'ispell-pdict-save) #'ignore))
+      (while (forward-word)
+        (auto-correct-fix-and-add nil)))
+    (ispell-pdict-save)))
+
+;;;###autoload
+(defun auto-correct-scan-region (start end)
+  "Scan the region between START and END for misspelled words.
+
+Interactively, START and END are the current region.
+
+When a misspelled word is found, offer to correct the misspelled
+word and auto-correct the typo in the future.
+
+When `auto-correct-mode' is enabled, use the `ispell' command
+instead."
+  (interactive "r")
+  (save-restriction
+    (narrow-to-region start end)
+    (auto-correct-scan-buffer)))
+
+;;;###autoload
+(defun auto-correct-scan ()
+  "Scan the buffer or region for misspelled words.
+
+When a misspelled word is found, offer to correct the misspelled
+word and auto-correct the typo in the future.
+
+When `auto-correct-mode' is enabled, use the `ispell' command
+instead."
+  (interactive)
+  (if (region-active-p)
+      (auto-correct-scan-region (region-beginning) (region-end))
+    (auto-correct-scan-buffer)))
+
+(provide 'auto-correct)
+
+;;; auto-correct.el ends here