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1 ;;; company-semantic.el --- company-mode completion back-end using Semantic
2
3 ;; Copyright (C) 2009-2011, 2013 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
31 (defvar semantic-idle-summary-function)
32 (declare-function semantic-documentation-for-tag "semantic/doc" )
33 (declare-function semantic-analyze-current-context "semantic/analyze")
34 (declare-function semantic-analyze-possible-completions "semantic/complete")
35 (declare-function semantic-analyze-find-tags-by-prefix "semantic/analyze/fcn")
36 (declare-function semantic-tag-class "semantic/tag")
37 (declare-function semantic-tag-name "semantic/tag")
38 (declare-function semantic-tag-start "semantic/tag")
39 (declare-function semantic-tag-buffer "semantic/tag")
40 (declare-function semantic-active-p "semantic")
41
42 (defgroup company-semantic nil
43 "Completion back-end using Semantic."
44 :group 'company)
45
46 (defcustom company-semantic-metadata-function 'company-semantic-summary-and-doc
47 "The function turning a semantic tag into doc information."
48 :type 'function)
49
50 (defvar company-semantic-modes '(c-mode c++-mode jde-mode java-mode))
51
52 (defvar company-semantic--current-tags nil
53 "Tags for the current context.")
54 (make-variable-buffer-local 'company-semantic--current-tags)
55
56 (defun company-semantic-documentation-for-tag (tag)
57 (when (semantic-tag-buffer tag)
58 ;; When TAG's buffer is unknown, the function below raises an error.
59 (semantic-documentation-for-tag tag)))
60
61 (defun company-semantic-doc-or-summary (tag)
62 (or (company-semantic-documentation-for-tag tag)
63 (and (require 'semantic-idle nil t)
64 (require 'semantic/idle nil t)
65 (funcall semantic-idle-summary-function tag nil t))))
66
67 (defun company-semantic-summary-and-doc (tag)
68 (debug)
69 (let ((doc (company-semantic-documentation-for-tag tag))
70 (summary (funcall semantic-idle-summary-function tag nil t)))
71 (and (stringp doc)
72 (string-match "\n*\\(.*\\)$" doc)
73 (setq doc (match-string 1 doc)))
74 (concat summary
75 (when doc
76 (if (< (+ (length doc) (length summary) 4) (window-width))
77 " -- "
78 "\n"))
79 doc)))
80
81 (defun company-semantic-doc-buffer (tag)
82 (let ((doc (company-semantic-documentation-for-tag tag)))
83 (when doc
84 (company-doc-buffer
85 (concat (funcall semantic-idle-summary-function tag nil t)
86 "\n"
87 doc)))))
88
89 (defsubst company-semantic-completions (prefix)
90 (ignore-errors
91 (let ((completion-ignore-case nil)
92 (context (semantic-analyze-current-context)))
93 (setq company-semantic--current-tags
94 (semantic-analyze-possible-completions context))
95 (all-completions prefix company-semantic--current-tags))))
96
97 (defun company-semantic-completions-raw (prefix)
98 (setq company-semantic--current-tags nil)
99 (dolist (tag (semantic-analyze-find-tags-by-prefix prefix))
100 (unless (eq (semantic-tag-class tag) 'include)
101 (push tag company-semantic--current-tags)))
102 (delete "" (mapcar 'semantic-tag-name company-semantic--current-tags)))
103
104 (defun company-semantic--pre-prefix-length (prefix-length)
105 "Sum up the length of all chained symbols before POS.
106 Symbols are chained by \".\" or \"->\"."
107 (save-excursion
108 (let ((pos (point)))
109 (goto-char (- (point) prefix-length))
110 (while (looking-back "->\\|\\.")
111 (goto-char (match-beginning 0))
112 (skip-syntax-backward "w_"))
113 (- pos (point)))))
114
115 (defun company-semantic--grab ()
116 "Grab the semantic prefix, but return everything before -> or . as length."
117 (let ((symbol (company-grab-symbol)))
118 (when symbol
119 (cons symbol (company-semantic--pre-prefix-length (length symbol))))))
120
121 ;;;###autoload
122 (defun company-semantic (command &optional arg &rest ignored)
123 "`company-mode' completion back-end using CEDET Semantic."
124 (interactive (list 'interactive))
125 (case command
126 (interactive (company-begin-backend 'company-semantic))
127 (prefix (and (featurep 'semantic)
128 (semantic-active-p)
129 (memq major-mode company-semantic-modes)
130 (not (company-in-string-or-comment))
131 (or (company-semantic--grab) 'stop)))
132 (candidates (if (and (equal arg "")
133 (not (looking-back "->\\|\\.")))
134 (company-semantic-completions-raw arg)
135 (company-semantic-completions arg)))
136 (meta (funcall company-semantic-metadata-function
137 (assoc arg company-semantic--current-tags)))
138 (doc-buffer (company-semantic-doc-buffer
139 (assoc arg company-semantic--current-tags)))
140 ;; Because "" is an empty context and doesn't return local variables.
141 (no-cache (equal arg ""))
142 (location (let ((tag (assoc arg company-semantic--current-tags)))
143 (when (buffer-live-p (semantic-tag-buffer tag))
144 (cons (semantic-tag-buffer tag)
145 (semantic-tag-start tag)))))))
146
147 (provide 'company-semantic)
148 ;;; company-semantic.el ends here