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

   1 ;;; company-elisp.el --- A company-mode completion back-end for emacs-lisp-mode
   2
   3 ;; Copyright (C) 2009, 2011  Free Software Foundation, Inc.
   4
   5 ;; Author: Nikolaj Schumacher
   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 'company)
  29 (eval-when-compile (require 'cl))
  30 (require 'help-mode)
  31
  32 (defcustom company-elisp-detect-function-context t
  33   "*If enabled, offer Lisp functions only in appropriate contexts.
  34 Functions are offered for completion only after ' and \(."
  35   :group 'company
  36   :type '(choice (const :tag "Off" nil)
  37                  (const :tag "On" t)))
  38
  39 (defun company-grab-lisp-symbol ()
  40   (let ((prefix (company-grab-symbol)))
  41     (if prefix
  42         (unless (and (company-in-string-or-comment)
  43                      (/= (char-before (- (point) (length prefix))) ?`))
  44           prefix)
  45       'stop)))
  46
  47 (defun company-elisp-predicate (symbol)
  48   (or (boundp symbol)
  49       (fboundp symbol)))
  50
  51 (defvar company-elisp-parse-limit 30)
  52 (defvar company-elisp-parse-depth 100)
  53
  54 (defvar company-elisp-binding-regexp
  55   (concat "([ \t\n]*\\_<" (regexp-opt '("let" "defun" "defmacro" "defsubst"
  56                                         "lambda" "lexical-let" "flet" "labels"))
  57           "\\*?")
  58   "Regular expression matching sexps containing variable bindings.")
  59
  60 (defvar company-elisp-binding-regexp-1
  61   (concat "([ \t\n]*\\_<" (regexp-opt '("dolist" "dotimes")))
  62   "Regular expression matching sexps containing one variable binding.")
  63
  64 (defun company-elisp-parse-local (prefix vars)
  65   (let ((regexp (concat "[ \t\n]*\\(\\_<" (regexp-quote prefix)
  66                         "\\(?:\\sw\\|\\s_\\)*\\_>\\)"))
  67         (pos (point)))
  68     (ignore-errors
  69       (save-excursion
  70         (dotimes (i company-elisp-parse-depth)
  71           (up-list -1)
  72           (save-excursion
  73             (cond
  74              ((looking-at company-elisp-binding-regexp)
  75               (down-list 2)
  76               (ignore-errors
  77                 (dotimes (i company-elisp-parse-limit)
  78                   (save-excursion
  79                     (when (looking-at "[ \t\n]*(")
  80                       (down-list 1))
  81                     (and (looking-at regexp)
  82                          ;; Don't add incomplete text as candidate.
  83                          (not (eq (match-end 0) pos))
  84                          (add-to-list 'vars (match-string-no-properties 1))))
  85                   (forward-sexp))))
  86              ((looking-at company-elisp-binding-regexp-1)
  87               (down-list 2)
  88               (and (looking-at regexp)
  89                    ;; Don't add incomplete text as candidate.
  90                    (not (eq (match-end 0) pos))
  91                    (add-to-list 'vars (match-string-no-properties 1)))))))))
  92     vars))
  93
  94 (defun company-elisp-candidates (prefix)
  95   (let* ((completion-ignore-case nil)
  96          (before (char-before (- (point) (length prefix))))
  97          (predicate (if (and company-elisp-detect-function-context
  98                              (not (eq before ?')))
  99                         (if (eq before ?\()
 100                             'fboundp
 101                           'boundp)
 102                       'company-elisp-predicate))
 103          (candidates (all-completions prefix obarray predicate)))
 104     (company-elisp-parse-local prefix candidates)))
 105
 106 (defun company-elisp-doc (symbol)
 107   (let* ((symbol (intern symbol))
 108          (doc (if (fboundp symbol)
 109                   (documentation symbol t)
 110                 (documentation-property symbol 'variable-documentation t))))
 111     (and (stringp doc)
 112          (string-match ".*$" doc)
 113          (match-string 0 doc))))
 114
 115 ;;;###autoload
 116 (defun company-elisp (command &optional arg &rest ignored)
 117   "A `company-mode' completion back-end for `emacs-lisp-mode'."
 118   (interactive (list 'interactive))
 119   (case command
 120     (interactive (company-begin-backend 'company-elisp))
 121     (prefix (and (eq (derived-mode-p 'emacs-lisp-mode) 'emacs-lisp-mode)
 122                  (company-grab-lisp-symbol)))
 123     (candidates (company-elisp-candidates arg))
 124     (meta (company-elisp-doc arg))
 125     (doc-buffer (let ((symbol (intern arg)))
 126                   (save-window-excursion
 127                     (when (or (ignore-errors (describe-function symbol))
 128                               (ignore-errors (describe-variable symbol)))
 129                       (help-buffer)))))
 130     (location (let ((sym (intern arg)))
 131                 (or (ignore-errors (find-definition-noselect sym nil))
 132                     (ignore-errors (find-definition-noselect sym 'defvar))
 133                     (ignore-errors (find-definition-noselect sym t)))))))
 134
 135 (provide 'company-elisp)
 136 ;;; company-elisp.el ends here