code.delx.au - gnu-emacs-elpa/blob - company-capf.el

   1 ;;; company-capf.el --- company-mode completion-at-point-functions back-end -*- lexical-binding: t -*-
   2
   3 ;; Copyright (C) 2013-2014  Free Software Foundation, Inc.
   4
   5 ;; Author: Stefan Monnier <monnier@iro.umontreal.ca>
   6
   7 ;; This file is part of GNU Emacs.
   8
   9 ;; GNU Emacs is free software: you can redistribute it and/or modify
  10 ;; it under the terms of the GNU General Public License as published by
  11 ;; the Free Software Foundation, either version 3 of the License, or
  12 ;; (at your option) any later version.
  13
  14 ;; GNU Emacs is distributed in the hope that it will be useful,
  15 ;; but WITHOUT ANY WARRANTY; without even the implied warranty of
  16 ;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  17 ;; GNU General Public License for more details.
  18
  19 ;; You should have received a copy of the GNU General Public License
  20 ;; along with GNU Emacs.  If not, see <http://www.gnu.org/licenses/>.
  21
  22
  23 ;;; Commentary:
  24 ;;
  25
  26 ;;; Code:
  27
  28 (require 'cl-lib)
  29
  30 (defvar company--capf-data nil)
  31 (make-variable-buffer-local 'company--capf-data)
  32
  33 (defun company--capf-clear-data (&optional _ignore)
  34   (setq company--capf-data nil)
  35   (remove-hook 'company-completion-cancelled-hook 'company--capf-clear-data t)
  36   (remove-hook 'company-completion-finished-hook 'company--capf-clear-data t))
  37
  38 (defun company--capf-data ()
  39   ;; Ignore tags-completion-at-point-function because it subverts company-etags
  40   ;; in the default value of company-backends, where the latter comes later.
  41   (cl-letf* (((default-value 'completion-at-point-functions) nil)
  42              (data (run-hook-wrapped 'completion-at-point-functions
  43                                      ;; Ignore misbehaving functions.
  44                                      #'completion--capf-wrapper 'optimist)))
  45     (when (and (consp (cdr data)) (numberp (nth 1 data))) data)))
  46
  47 (defun company-capf (command &optional arg &rest _args)
  48   "`company-mode' back-end using `completion-at-point-functions'.
  49 Requires Emacs 24.1 or newer."
  50   (interactive (list 'interactive))
  51   (pcase command
  52     (`interactive (company-begin-backend 'company-capf))
  53     (`prefix
  54      (let ((res (company--capf-data)))
  55        (when res
  56          (if (> (nth 2 res) (point))
  57              'stop
  58            (setq company--capf-data res)
  59            (add-hook 'company-completion-cancelled-hook 'company--capf-clear-data nil t)
  60            (add-hook 'company-completion-finished-hook 'company--capf-clear-data nil t)
  61            (buffer-substring-no-properties (nth 1 res) (point))))))
  62     (`candidates
  63      (let ((res company--capf-data))
  64        (when res
  65          (let* ((table (nth 3 res))
  66                 (pred (plist-get (nthcdr 4 res) :predicate))
  67                 (meta (completion-metadata
  68                       (buffer-substring (nth 1 res) (nth 2 res))
  69                       table pred))
  70                 (sortfun (cdr (assq 'display-sort-function meta)))
  71                 (candidates (completion-all-completions arg table pred (length arg)))
  72                 (last (last candidates))
  73                 (base-size (and (numberp (cdr last)) (cdr last))))
  74            (when base-size
  75              (setcdr last nil))
  76            (when sortfun
  77              (setq candidates (funcall sortfun candidates)))
  78            (if (not (zerop (or base-size 0)))
  79                (let ((before (substring arg 0 base-size)))
  80                  (mapcar (lambda (candidate)
  81                            (concat before candidate))
  82                          candidates))
  83              candidates)))))
  84     (`sorted
  85      (let ((res company--capf-data))
  86        (when res
  87          (let ((meta (completion-metadata
  88                       (buffer-substring (nth 1 res) (nth 2 res))
  89                       (nth 3 res) (plist-get (nthcdr 4 res) :predicate))))
  90            (cdr (assq 'display-sort-function meta))))))
  91     (`match
  92      ;; Can't just use 0 when base-size (see above) is non-zero.
  93      (let ((start (if (get-text-property 0 'font-lock-face arg)
  94                       0
  95                     (next-single-property-change 0 'font-lock-face arg))))
  96        (when start
  97          ;; completions-common-part comes first, but we can't just look for this
  98          ;; value because it can be in a list.
  99          (or
 100           (let ((value (get-text-property start 'font-lock-face arg)))
 101             (text-property-not-all start (length arg)
 102                                    'font-lock-face value arg))
 103           (length arg)))))
 104     (`duplicates t)
 105     (`no-cache t)   ;Not much can be done here, as long as we handle
 106                     ;non-prefix matches.
 107     (`meta
 108      (let ((f (plist-get (nthcdr 4 company--capf-data) :company-docsig)))
 109        (when f (funcall f arg))))
 110     (`doc-buffer
 111      (let ((f (plist-get (nthcdr 4 company--capf-data) :company-doc-buffer)))
 112        (when f (funcall f arg))))
 113     (`location
 114      (let ((f (plist-get (nthcdr 4 company--capf-data) :company-location)))
 115        (when f (funcall f arg))))
 116     (`annotation
 117      (save-excursion
 118        ;; FIXME: `company-begin' sets `company-point' after calling
 119        ;; `company--begin-new'.  We shouldn't rely on `company-point' here,
 120        ;; better to cache the capf-data value instead.
 121        (when company-point
 122          (goto-char company-point))
 123        (let ((f (plist-get (nthcdr 4 company--capf-data) :annotation-function)))
 124          (when f (funcall f arg)))))
 125     (`require-match
 126      (plist-get (nthcdr 4 company--capf-data) :company-require-match))
 127     (`init nil)      ;Don't bother: plenty of other ways to initialize the code.
 128     (`post-completion
 129      (let* ((res company--capf-data)
 130             (exit-function (plist-get (nthcdr 4 res) :exit-function)))
 131        (if exit-function
 132            (funcall exit-function arg 'finished))))
 133     ))
 134
 135 (provide 'company-capf)
 136
 137 ;;; company-capf.el ends here