code.delx.au - gnu-emacs-elpa/blob - packages/swiper/ivy.el

   1 ;;; ivy.el --- Incremental Vertical completYon -*- lexical-binding: t -*-
   2
   3 ;; Copyright (C) 2015  Free Software Foundation, Inc.
   4
   5 ;; Author: Oleh Krehel <ohwoeowho@gmail.com>
   6 ;; URL: https://github.com/abo-abo/swiper
   7 ;; Version: 0.2.2
   8 ;; Package-Requires: ((emacs "24.1"))
   9 ;; Keywords: matching
  10
  11 ;; This file is part of GNU Emacs.
  12
  13 ;; This file 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, or (at your option)
  16 ;; 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 ;; For a full copy of the GNU General Public License
  24 ;; see <http://www.gnu.org/licenses/>.
  25
  26 ;;; Commentary:
  27 ;;
  28 ;; This package provides `ivy-read' as an alternative to
  29 ;; `completing-read' and similar functions.
  30 ;;
  31 ;; There's no intricate code to determine the best candidate.
  32 ;; Instead, the user can navigate to it with `ivy-next-line' and
  33 ;; `ivy-previous-line'.
  34 ;;
  35 ;; The matching is done by splitting the input text by spaces and
  36 ;; re-building it into a regex.
  37 ;; So "for example" is transformed into "\\(for\\).*\\(example\\)".
  38
  39 ;;; Code:
  40 ;;* Customization
  41 (defgroup ivy nil
  42   "Incremental vertical completion."
  43   :group 'convenience)
  44
  45 (defface ivy-current-match
  46   '((t (:inherit highlight)))
  47   "Face used by Ivy for highlighting first match.")
  48
  49 (defcustom ivy-height 10
  50   "Number of lines for the minibuffer window."
  51   :type 'integer)
  52
  53 (defcustom ivy-count-format "%-4d "
  54   "The style of showing the current candidate count for `ivy-read'.
  55 Set this to nil if you don't want the count."
  56   :type 'string)
  57
  58 (defcustom ivy-wrap nil
  59   "Whether to wrap around after the first and last candidate."
  60   :type 'boolean)
  61
  62 (defcustom ivy-on-del-error-function 'minibuffer-keyboard-quit
  63   "The handler for when `ivy-backward-delete-char' throws.
  64 This is usually meant as a quick exit out of the minibuffer."
  65   :type 'function)
  66
  67 ;;* User Visible
  68 ;;** Keymap
  69 (require 'delsel)
  70 (defvar ivy-minibuffer-map
  71   (let ((map (make-sparse-keymap)))
  72     (define-key map (kbd "C-m") 'ivy-done)
  73     (define-key map (kbd "C-n") 'ivy-next-line)
  74     (define-key map (kbd "C-p") 'ivy-previous-line)
  75     (define-key map (kbd "C-s") 'ivy-next-line-or-history)
  76     (define-key map (kbd "C-r") 'ivy-previous-line-or-history)
  77     (define-key map (kbd "SPC") 'self-insert-command)
  78     (define-key map (kbd "DEL") 'ivy-backward-delete-char)
  79     (define-key map (kbd "M-<") 'ivy-beginning-of-buffer)
  80     (define-key map (kbd "M->") 'ivy-end-of-buffer)
  81     (define-key map (kbd "M-n") 'ivy-next-history-element)
  82     (define-key map (kbd "M-p") 'ivy-previous-history-element)
  83     (define-key map (kbd "C-g") 'minibuffer-keyboard-quit)
  84     map)
  85   "Keymap used in the minibuffer.")
  86
  87 (defvar ivy-history nil
  88   "History list of candidates entered in the minibuffer.
  89
  90 Maximum length of the history list is determined by the value
  91 of `history-length', which see.")
  92
  93 (defvar ivy-require-match t
  94   "Store require-match. See `completing-read'.")
  95
  96 ;;** Commands
  97 (defun ivy-done ()
  98   "Exit the minibuffer with the selected candidate."
  99   (interactive)
 100   (delete-minibuffer-contents)
 101   (if (zerop ivy--length)
 102       (when (memq ivy-require-match '(nil confirm confirm-after-completion))
 103         (insert ivy-text)
 104         (setq ivy-exit 'done))
 105     (insert ivy--current)
 106     (setq ivy-exit 'done))
 107   (exit-minibuffer))
 108
 109 (defun ivy-beginning-of-buffer ()
 110   "Select the first completion candidate."
 111   (interactive)
 112   (setq ivy--index 0))
 113
 114 (defun ivy-end-of-buffer ()
 115   "Select the last completion candidate."
 116   (interactive)
 117   (setq ivy--index (1- ivy--length)))
 118
 119 (defun ivy-next-line (&optional arg)
 120   "Move cursor vertically down ARG candidates."
 121   (interactive "p")
 122   (setq arg (or arg 1))
 123   (cl-incf ivy--index arg)
 124   (when (>= ivy--index (1- ivy--length))
 125     (if ivy-wrap
 126         (ivy-beginning-of-buffer)
 127       (setq ivy--index (1- ivy--length)))))
 128
 129 (defun ivy-next-line-or-history (&optional arg)
 130   "Move cursor vertically down ARG candidates.
 131 If the input is empty, select the previous history element instead."
 132   (interactive "p")
 133   (when (string= ivy-text "")
 134     (ivy-previous-history-element 1))
 135   (ivy-next-line arg))
 136
 137 (defun ivy-previous-line (&optional arg)
 138   "Move cursor vertically up ARG candidates."
 139   (interactive "p")
 140   (setq arg (or arg 1))
 141   (cl-decf ivy--index arg)
 142   (when (< ivy--index 0)
 143     (if ivy-wrap
 144         (ivy-end-of-buffer)
 145       (setq ivy--index 0))))
 146
 147 (defun ivy-previous-line-or-history (arg)
 148   "Move cursor vertically up ARG candidates.
 149 If the input is empty, select the previous history element instead."
 150   (interactive "p")
 151   (when (string= ivy-text "")
 152     (ivy-previous-history-element 1))
 153   (ivy-previous-line arg))
 154
 155 (defun ivy-previous-history-element (arg)
 156   "Forward to `previous-history-element' with ARG."
 157   (interactive "p")
 158   (previous-history-element arg)
 159   (move-end-of-line 1))
 160
 161 (defun ivy-next-history-element (arg)
 162   "Forward to `next-history-element' with ARG."
 163   (interactive "p")
 164   (next-history-element arg)
 165   (move-end-of-line 1))
 166
 167 (defun ivy-backward-delete-char ()
 168   "Forward to `backward-delete-char'.
 169 On error (read-only), call `ivy-on-del-error-function'."
 170   (interactive)
 171   (condition-case nil
 172       (backward-delete-char 1)
 173     (error
 174      (when ivy-on-del-error-function
 175        (funcall ivy-on-del-error-function)))))
 176
 177 ;;** Entry Point
 178 (defun ivy-read (prompt collection
 179                  &optional initial-input keymap preselect update-fn)
 180   "Read a string in the minibuffer, with completion.
 181
 182 PROMPT is a string to prompt with; normally it ends in a colon
 183 and a space.  When PROMPT contains %d, it will be updated with
 184 the current number of matching candidates.
 185 See also `ivy-count-format'.
 186
 187 COLLECTION is a list of strings.
 188
 189 If INITIAL-INPUT is non-nil, insert it in the minibuffer initially.
 190
 191 KEYMAP is composed together with `ivy-minibuffer-map'.
 192
 193 If PRESELECT is non-nil select the corresponding candidate out of
 194 the ones that match INITIAL-INPUT.
 195
 196 UPDATE-FN is called each time the current candidate(s) is changed."
 197   (cl-case (length collection)
 198     (0 nil)
 199     (1 (car collection))
 200     (t
 201      (setq ivy--index (or
 202                        (and preselect
 203                             (ivy--preselect-index
 204                              collection initial-input preselect))
 205                        0))
 206      (setq ivy--old-re nil)
 207      (setq ivy--old-cands nil)
 208      (setq ivy-text "")
 209      (setq ivy--all-candidates collection)
 210      (setq ivy--update-fn update-fn)
 211      (setq ivy-exit nil)
 212      (setq ivy--default (or (thing-at-point 'symbol) ""))
 213      (setq ivy--prompt
 214            (cond ((string-match "%.*d" prompt)
 215                   prompt)
 216                  ((string-match "%.*d" ivy-count-format)
 217                   (concat ivy-count-format prompt))
 218                  (t
 219                   nil)))
 220      (setq ivy--action nil)
 221      (prog1
 222          (unwind-protect
 223               (minibuffer-with-setup-hook
 224                   #'ivy--minibuffer-setup
 225                 (let ((res (read-from-minibuffer
 226                             prompt
 227                             initial-input
 228                             (make-composed-keymap keymap ivy-minibuffer-map)
 229                             nil
 230                             'ivy-history)))
 231                   (when (eq ivy-exit 'done)
 232                     (pop ivy-history)
 233                     (setq ivy-history
 234                           (cons ivy-text (delete ivy-text ivy-history)))
 235                     res)))
 236            (remove-hook 'post-command-hook #'ivy--exhibit))
 237        (when ivy--action
 238          (funcall ivy--action))))))
 239
 240 (defun ivy-completing-read (prompt collection
 241                             &optional predicate require-match initial-input
 242                               _history def _inherit-input-method)
 243   "Read a string in the minibuffer, with completion.
 244
 245 This is an interface that conforms to `completing-read', so that
 246 it can be used for `completing-read-function'.
 247
 248 PROMPT is a string to prompt with; normally it ends in a colon and a space.
 249 COLLECTION can be a list of strings, an alist, an obarray or a hash table.
 250 PREDICATE limits completion to a subset of COLLECTION.
 251
 252 REQUIRE-MATCH is stored into `ivy-require-match'. See `completing-read'.
 253 INITIAL-INPUT is a string that can be inserted into the minibuffer initially.
 254 _HISTORY is ignored for now.
 255 DEF is the default value.
 256 _INHERIT-INPUT-METHOD is ignored for now.
 257
 258 The history, defaults and input-method arguments are ignored for now."
 259   (cond ((functionp collection)
 260          (setq collection (all-completions "" collection))
 261          (setq initial-input nil))
 262         ((hash-table-p collection)
 263          (error "Hash table as a collection unsupported"))
 264         ((listp (car collection))
 265          (setq collection (mapcar #'car collection))))
 266   (when predicate
 267     (setq collection (cl-remove-if-not predicate collection)))
 268   (when (listp def)
 269     (setq def (car def)))
 270   (setq ivy-require-match require-match)
 271   (ivy-read prompt collection initial-input nil def))
 272
 273 ;;;###autoload
 274 (define-minor-mode ivy-mode
 275     "Toggle Ivy mode on or off.
 276 With ARG, turn Ivy mode on if arg is positive, off otherwise.
 277 Turning on Ivy mode will set `completing-read-function' to
 278 `ivy-completing-read'."
 279   :group 'ivy
 280   :global t
 281   :lighter " ivy"
 282   (if ivy-mode
 283       (setq completing-read-function 'ivy-completing-read)
 284     (setq completing-read-function 'completing-read-default)))
 285
 286 (defvar ivy--action nil
 287   "Store a function to call at the end of `ivy--read'.")
 288
 289 (defun ivy--preselect-index (candidates initial-input preselect)
 290   "Return the index in CANDIDATES filtered by INITIAL-INPUT for PRESELECT."
 291   (when initial-input
 292     (setq candidates
 293           (cl-remove-if-not
 294            (lambda (x)
 295              (string-match initial-input x))
 296            candidates)))
 297   (cl-position-if
 298    (lambda (x)
 299      (string-match preselect x))
 300    candidates))
 301
 302 (defvar ivy-text ""
 303   "Stores the user's string as it is typed in.")
 304
 305 (defvar ivy-exit nil
 306   "Store 'done if the completion was successfully selected.
 307 Otherwise, store nil.")
 308
 309 ;;* Implementation
 310 ;;** Regex
 311 (defvar ivy--subexps 0
 312   "Number of groups in the current `ivy--regex'.")
 313
 314 (defvar ivy--regex-hash
 315   (make-hash-table :test 'equal)
 316   "Store pre-computed regex.")
 317
 318 (defun ivy--regex (str)
 319   "Re-build regex from STR in case it has a space."
 320   (let ((hashed (gethash str ivy--regex-hash)))
 321     (if hashed
 322         (prog1 (cdr hashed)
 323           (setq ivy--subexps (car hashed)))
 324       (cdr (puthash str
 325                     (let ((subs (split-string str " +" t)))
 326                       (if (= (length subs) 1)
 327                           (cons
 328                            (setq ivy--subexps 0)
 329                            (car subs))
 330                         (cons
 331                          (setq ivy--subexps (length subs))
 332                          (mapconcat
 333                           (lambda (x) (format "\\(%s\\)" x))
 334                           subs
 335                           ".*"))))
 336                     ivy--regex-hash)))))
 337
 338 ;;** Rest
 339 (defun ivy--minibuffer-setup ()
 340   "Setup ivy completion in the minibuffer."
 341   (set (make-local-variable 'completion-show-inline-help) nil)
 342   (set (make-local-variable 'minibuffer-default-add-function)
 343        (lambda ()
 344          (list ivy--default)))
 345   (use-local-map (make-composed-keymap ivy-minibuffer-map
 346                                        (current-local-map)))
 347   (setq-local max-mini-window-height ivy-height)
 348   (add-hook 'post-command-hook #'ivy--exhibit nil t)
 349   ;; show completions with empty input
 350   (ivy--exhibit))
 351
 352 (defvar ivy--all-candidates nil
 353   "Store the candidates passed to `ivy-read'.")
 354
 355 (defvar ivy--index 0
 356   "Store the index of the current candidate.")
 357
 358 (defvar ivy--length 0
 359   "Store the amount of viable candidates.")
 360
 361 (defvar ivy--current ""
 362   "Current candidate.")
 363
 364 (defvar ivy--default nil
 365   "Default initial input.")
 366
 367 (defvar ivy--update-fn nil
 368   "Current function to call when current candidate(s) update.")
 369
 370 (defun ivy--input ()
 371   "Return the current minibuffer input."
 372   ;; assume one-line minibuffer input
 373   (buffer-substring-no-properties
 374    (minibuffer-prompt-end)
 375    (line-end-position)))
 376
 377 (defun ivy--cleanup ()
 378   "Delete the displayed completion candidates."
 379   (save-excursion
 380     (goto-char (minibuffer-prompt-end))
 381     (delete-region (line-end-position) (point-max))))
 382
 383 (defvar ivy--prompt nil
 384   "Store the format-style prompt.
 385 When non-nil, it should contain one %d.")
 386
 387 (defun ivy--insert-prompt ()
 388   "Update the prompt according to `ivy--prompt'."
 389   (when ivy--prompt
 390     (let ((inhibit-read-only t)
 391           (n-str (format ivy--prompt ivy--length)))
 392       (save-excursion
 393         (goto-char (point-min))
 394         (delete-region (point-min) (minibuffer-prompt-end))
 395         (set-text-properties
 396          0 (length n-str)
 397          '(front-sticky t rear-nonsticky t field t read-only t face minibuffer-prompt)
 398          n-str)
 399         (insert n-str))
 400       ;; get out of the prompt area
 401       (constrain-to-field nil (point-max)))))
 402
 403 (defun ivy--exhibit ()
 404   "Insert Ivy completions display.
 405 Should be run via minibuffer `post-command-hook'."
 406   (setq ivy-text (ivy--input))
 407   (ivy--cleanup)
 408   (let ((text (ivy-completions
 409                ivy-text
 410                ivy--all-candidates))
 411         (buffer-undo-list t)
 412         deactivate-mark)
 413     (when ivy--update-fn
 414       (funcall ivy--update-fn))
 415     (ivy--insert-prompt)
 416     ;; Do nothing if while-no-input was aborted.
 417     (when (stringp text)
 418       (save-excursion
 419         (forward-line 1)
 420         (insert text)))))
 421
 422 (defvar ivy--old-re nil
 423   "Store the old regexp.")
 424
 425 (defvar ivy--old-cands nil
 426   "Store the candidates matched by `ivy--old-re'.")
 427
 428 (defun ivy--add-face (str face)
 429   "Propertize STR with FACE.
 430 `font-lock-append-text-property' is used, since it's better than
 431 `propertize' or `add-face-text-property' in this case."
 432   (font-lock-append-text-property 0 (length str) 'face face str)
 433   str)
 434
 435 (defun ivy-completions (name candidates)
 436   "Return as text the current completions.
 437 NAME is a string of words separated by spaces that is used to
 438 build a regex.
 439 CANDIDATES is a list of strings."
 440   (let* ((re (ivy--regex name))
 441          (cands (if (and (equal re ivy--old-re)
 442                          ivy--old-cands)
 443                     ivy--old-cands
 444                   (ignore-errors
 445                     (cl-remove-if-not
 446                      (lambda (x) (string-match re x))
 447                      candidates))))
 448          (tail (nthcdr ivy--index ivy--old-cands))
 449          (ww (window-width))
 450          idx)
 451     (when (and tail ivy--old-cands)
 452       (unless (and (not (equal re ivy--old-re))
 453                    (setq ivy--index (cl-position re cands :test 'equal)))
 454         (while (and tail (null idx))
 455           ;; Compare with eq to handle equal duplicates in cands
 456           (setq idx (cl-position (pop tail) cands)))
 457         (setq ivy--index (or idx 0))))
 458     (setq ivy--old-re re)
 459     (setq ivy--length (length cands))
 460     (setq ivy--old-cands cands)
 461     (when (>= ivy--index ivy--length)
 462       (setq ivy--index (max (1- ivy--length) 0)))
 463     (if (null cands)
 464         ""
 465       (let* ((half-height (/ ivy-height 2))
 466              (start (max 0 (- ivy--index half-height)))
 467              (end (min (+ start (1- ivy-height)) ivy--length))
 468              (cands (cl-subseq cands start end))
 469              (index (min ivy--index half-height (1- (length cands)))))
 470         (setq ivy--current (copy-sequence (nth index cands)))
 471         (setf (nth index cands)
 472               (ivy--add-face ivy--current 'ivy-current-match))
 473         (let ((res (concat "\n" (mapconcat
 474                                  (lambda (s)
 475                                    (if (> (length s) ww)
 476                                        (concat (substring s 0 (- ww 3)) "...")
 477                                      s))
 478                                  cands "\n"))))
 479           (put-text-property 0 (length res) 'read-only nil res)
 480           res)))))
 481
 482 (provide 'ivy)
 483
 484 ;;; ivy.el ends here