Don't cut off last character of commit descriptions.
[git/git.git] / contrib / emacs / git-blame.el
1 ;;; git-blame.el --- Minor mode for incremental blame for Git -*- coding: utf-8 -*-
2 ;;
3 ;; Copyright (C) 2007 David Kågedal
4 ;;
5 ;; Authors: David Kågedal <davidk@lysator.liu.se>
6 ;; Created: 31 Jan 2007
7 ;; Message-ID: <87iren2vqx.fsf@morpheus.local>
8 ;; License: GPL
9 ;; Keywords: git, version control, release management
10 ;;
11 ;; Compatibility: Emacs21, Emacs22 and EmacsCVS
12 ;; Git 1.5 and up
13
14 ;; This file is *NOT* part of GNU Emacs.
15 ;; This file is distributed under the same terms as GNU Emacs.
16
17 ;; This program is free software; you can redistribute it and/or
18 ;; modify it under the terms of the GNU General Public License as
19 ;; published by the Free Software Foundation; either version 2 of
20 ;; the License, or (at your option) any later version.
21
22 ;; This program is distributed in the hope that it will be
23 ;; useful, but WITHOUT ANY WARRANTY; without even the implied
24 ;; warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR
25 ;; PURPOSE. See the GNU General Public License for more details.
26
27 ;; You should have received a copy of the GNU General Public
28 ;; License along with this program; if not, write to the Free
29 ;; Software Foundation, Inc., 59 Temple Place, Suite 330, Boston,
30 ;; MA 02111-1307 USA
31
32 ;; http://www.fsf.org/copyleft/gpl.html
33
34
35 ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
36 ;;
37 ;;; Commentary:
38 ;;
39 ;; Here is an Emacs implementation of incremental git-blame. When you
40 ;; turn it on while viewing a file, the editor buffer will be updated by
41 ;; setting the background of individual lines to a color that reflects
42 ;; which commit it comes from. And when you move around the buffer, a
43 ;; one-line summary will be shown in the echo area.
44
45 ;;; Installation:
46 ;;
47 ;; To use this package, put it somewhere in `load-path' (or add
48 ;; directory with git-blame.el to `load-path'), and add the following
49 ;; line to your .emacs:
50 ;;
51 ;; (require 'git-blame)
52 ;;
53 ;; If you do not want to load this package before it is necessary, you
54 ;; can make use of the `autoload' feature, e.g. by adding to your .emacs
55 ;; the following lines
56 ;;
57 ;; (autoload 'git-blame-mode "git-blame"
58 ;; "Minor mode for incremental blame for Git." t)
59 ;;
60 ;; Then first use of `M-x git-blame-mode' would load the package.
61
62 ;;; Compatibility:
63 ;;
64 ;; It requires GNU Emacs 21 or later and Git 1.5.0 and up
65 ;;
66 ;; If you'are using Emacs 20, try changing this:
67 ;;
68 ;; (overlay-put ovl 'face (list :background
69 ;; (cdr (assq 'color (cddddr info)))))
70 ;;
71 ;; to
72 ;;
73 ;; (overlay-put ovl 'face (cons 'background-color
74 ;; (cdr (assq 'color (cddddr info)))))
75
76
77 ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
78 ;;
79 ;;; Code:
80
81 (eval-when-compile (require 'cl)) ; to use `push', `pop'
82
83
84 (defun git-blame-color-scale (&rest elements)
85 "Given a list, returns a list of triples formed with each
86 elements of the list.
87
88 a b => bbb bba bab baa abb aba aaa aab"
89 (let (result)
90 (dolist (a elements)
91 (dolist (b elements)
92 (dolist (c elements)
93 (setq result (cons (format "#%s%s%s" a b c) result)))))
94 result))
95
96 ;; (git-blame-color-scale "0c" "04" "24" "1c" "2c" "34" "14" "3c") =>
97 ;; ("#3c3c3c" "#3c3c14" "#3c3c34" "#3c3c2c" "#3c3c1c" "#3c3c24"
98 ;; "#3c3c04" "#3c3c0c" "#3c143c" "#3c1414" "#3c1434" "#3c142c" ...)
99
100 (defmacro git-blame-random-pop (l)
101 "Select a random element from L and returns it. Also remove
102 selected element from l."
103 ;; only works on lists with unique elements
104 `(let ((e (elt ,l (random (length ,l)))))
105 (setq ,l (remove e ,l))
106 e))
107
108 (defvar git-blame-log-oneline-format
109 "format:[%cr] %cn: %s"
110 "*Formatting option used for describing current line in the minibuffer.
111
112 This option is used to pass to git log --pretty= command-line option,
113 and describe which commit the current line was made.")
114
115 (defvar git-blame-dark-colors
116 (git-blame-color-scale "0c" "04" "24" "1c" "2c" "34" "14" "3c")
117 "*List of colors (format #RGB) to use in a dark environment.
118
119 To check out the list, evaluate (list-colors-display git-blame-dark-colors).")
120
121 (defvar git-blame-light-colors
122 (git-blame-color-scale "c4" "d4" "cc" "dc" "f4" "e4" "fc" "ec")
123 "*List of colors (format #RGB) to use in a light environment.
124
125 To check out the list, evaluate (list-colors-display git-blame-light-colors).")
126
127 (defvar git-blame-colors '()
128 "Colors used by git-blame. The list is built once when activating git-blame
129 minor mode.")
130
131 (defvar git-blame-ancient-color "dark green"
132 "*Color to be used for ancient commit.")
133
134 (defvar git-blame-autoupdate t
135 "*Automatically update the blame display while editing")
136
137 (defvar git-blame-proc nil
138 "The running git-blame process")
139 (make-variable-buffer-local 'git-blame-proc)
140
141 (defvar git-blame-overlays nil
142 "The git-blame overlays used in the current buffer.")
143 (make-variable-buffer-local 'git-blame-overlays)
144
145 (defvar git-blame-cache nil
146 "A cache of git-blame information for the current buffer")
147 (make-variable-buffer-local 'git-blame-cache)
148
149 (defvar git-blame-idle-timer nil
150 "An idle timer that updates the blame")
151 (make-variable-buffer-local 'git-blame-cache)
152
153 (defvar git-blame-update-queue nil
154 "A queue of update requests")
155 (make-variable-buffer-local 'git-blame-update-queue)
156
157 ;; FIXME: docstrings
158 (defvar git-blame-file nil)
159 (defvar git-blame-current nil)
160
161 (defvar git-blame-mode nil)
162 (make-variable-buffer-local 'git-blame-mode)
163
164 (defvar git-blame-mode-line-string " blame"
165 "String to display on the mode line when git-blame is active.")
166
167 (or (assq 'git-blame-mode minor-mode-alist)
168 (setq minor-mode-alist
169 (cons '(git-blame-mode git-blame-mode-line-string) minor-mode-alist)))
170
171 ;;;###autoload
172 (defun git-blame-mode (&optional arg)
173 "Toggle minor mode for displaying Git blame
174
175 With prefix ARG, turn the mode on if ARG is positive."
176 (interactive "P")
177 (cond
178 ((null arg)
179 (if git-blame-mode (git-blame-mode-off) (git-blame-mode-on)))
180 ((> (prefix-numeric-value arg) 0) (git-blame-mode-on))
181 (t (git-blame-mode-off))))
182
183 (defun git-blame-mode-on ()
184 "Turn on git-blame mode.
185
186 See also function `git-blame-mode'."
187 (make-local-variable 'git-blame-colors)
188 (if git-blame-autoupdate
189 (add-hook 'after-change-functions 'git-blame-after-change nil t)
190 (remove-hook 'after-change-functions 'git-blame-after-change t))
191 (git-blame-cleanup)
192 (let ((bgmode (cdr (assoc 'background-mode (frame-parameters)))))
193 (if (eq bgmode 'dark)
194 (setq git-blame-colors git-blame-dark-colors)
195 (setq git-blame-colors git-blame-light-colors)))
196 (setq git-blame-cache (make-hash-table :test 'equal))
197 (setq git-blame-mode t)
198 (git-blame-run))
199
200 (defun git-blame-mode-off ()
201 "Turn off git-blame mode.
202
203 See also function `git-blame-mode'."
204 (git-blame-cleanup)
205 (if git-blame-idle-timer (cancel-timer git-blame-idle-timer))
206 (setq git-blame-mode nil))
207
208 ;;;###autoload
209 (defun git-reblame ()
210 "Recalculate all blame information in the current buffer"
211 (interactive)
212 (unless git-blame-mode
213 (error "Git-blame is not active"))
214
215 (git-blame-cleanup)
216 (git-blame-run))
217
218 (defun git-blame-run (&optional startline endline)
219 (if git-blame-proc
220 ;; Should maybe queue up a new run here
221 (message "Already running git blame")
222 (let ((display-buf (current-buffer))
223 (blame-buf (get-buffer-create
224 (concat " git blame for " (buffer-name))))
225 (args '("--incremental" "--contents" "-")))
226 (if startline
227 (setq args (append args
228 (list "-L" (format "%d,%d" startline endline)))))
229 (setq args (append args
230 (list (file-name-nondirectory buffer-file-name))))
231 (setq git-blame-proc
232 (apply 'start-process
233 "git-blame" blame-buf
234 "git" "blame"
235 args))
236 (with-current-buffer blame-buf
237 (erase-buffer)
238 (make-local-variable 'git-blame-file)
239 (make-local-variable 'git-blame-current)
240 (setq git-blame-file display-buf)
241 (setq git-blame-current nil))
242 (set-process-filter git-blame-proc 'git-blame-filter)
243 (set-process-sentinel git-blame-proc 'git-blame-sentinel)
244 (process-send-region git-blame-proc (point-min) (point-max))
245 (process-send-eof git-blame-proc))))
246
247 (defun remove-git-blame-text-properties (start end)
248 (let ((modified (buffer-modified-p))
249 (inhibit-read-only t))
250 (remove-text-properties start end '(point-entered nil))
251 (set-buffer-modified-p modified)))
252
253 (defun git-blame-cleanup ()
254 "Remove all blame properties"
255 (mapcar 'delete-overlay git-blame-overlays)
256 (setq git-blame-overlays nil)
257 (remove-git-blame-text-properties (point-min) (point-max)))
258
259 (defun git-blame-update-region (start end)
260 "Rerun blame to get updates between START and END"
261 (let ((overlays (overlays-in start end)))
262 (while overlays
263 (let ((overlay (pop overlays)))
264 (if (< (overlay-start overlay) start)
265 (setq start (overlay-start overlay)))
266 (if (> (overlay-end overlay) end)
267 (setq end (overlay-end overlay)))
268 (setq git-blame-overlays (delete overlay git-blame-overlays))
269 (delete-overlay overlay))))
270 (remove-git-blame-text-properties start end)
271 ;; We can be sure that start and end are at line breaks
272 (git-blame-run (1+ (count-lines (point-min) start))
273 (count-lines (point-min) end)))
274
275 (defun git-blame-sentinel (proc status)
276 (with-current-buffer (process-buffer proc)
277 (with-current-buffer git-blame-file
278 (setq git-blame-proc nil)
279 (if git-blame-update-queue
280 (git-blame-delayed-update))))
281 ;;(kill-buffer (process-buffer proc))
282 ;;(message "git blame finished")
283 )
284
285 (defvar in-blame-filter nil)
286
287 (defun git-blame-filter (proc str)
288 (save-excursion
289 (set-buffer (process-buffer proc))
290 (goto-char (process-mark proc))
291 (insert-before-markers str)
292 (goto-char 0)
293 (unless in-blame-filter
294 (let ((more t)
295 (in-blame-filter t))
296 (while more
297 (setq more (git-blame-parse)))))))
298
299 (defun git-blame-parse ()
300 (cond ((looking-at "\\([0-9a-f]\\{40\\}\\) \\([0-9]+\\) \\([0-9]+\\) \\([0-9]+\\)\n")
301 (let ((hash (match-string 1))
302 (src-line (string-to-number (match-string 2)))
303 (res-line (string-to-number (match-string 3)))
304 (num-lines (string-to-number (match-string 4))))
305 (setq git-blame-current
306 (if (string= hash "0000000000000000000000000000000000000000")
307 nil
308 (git-blame-new-commit
309 hash src-line res-line num-lines))))
310 (delete-region (point) (match-end 0))
311 t)
312 ((looking-at "filename \\(.+\\)\n")
313 (let ((filename (match-string 1)))
314 (git-blame-add-info "filename" filename))
315 (delete-region (point) (match-end 0))
316 t)
317 ((looking-at "\\([a-z-]+\\) \\(.+\\)\n")
318 (let ((key (match-string 1))
319 (value (match-string 2)))
320 (git-blame-add-info key value))
321 (delete-region (point) (match-end 0))
322 t)
323 ((looking-at "boundary\n")
324 (setq git-blame-current nil)
325 (delete-region (point) (match-end 0))
326 t)
327 (t
328 nil)))
329
330 (defun git-blame-new-commit (hash src-line res-line num-lines)
331 (save-excursion
332 (set-buffer git-blame-file)
333 (let ((info (gethash hash git-blame-cache))
334 (inhibit-point-motion-hooks t)
335 (inhibit-modification-hooks t))
336 (when (not info)
337 ;; Assign a random color to each new commit info
338 ;; Take care not to select the same color multiple times
339 (let ((color (if git-blame-colors
340 (git-blame-random-pop git-blame-colors)
341 git-blame-ancient-color)))
342 (setq info (list hash src-line res-line num-lines
343 (git-describe-commit hash)
344 (cons 'color color))))
345 (puthash hash info git-blame-cache))
346 (goto-line res-line)
347 (while (> num-lines 0)
348 (if (get-text-property (point) 'git-blame)
349 (forward-line)
350 (let* ((start (point))
351 (end (progn (forward-line 1) (point)))
352 (ovl (make-overlay start end)))
353 (push ovl git-blame-overlays)
354 (overlay-put ovl 'git-blame info)
355 (overlay-put ovl 'help-echo hash)
356 (overlay-put ovl 'face (list :background
357 (cdr (assq 'color (nthcdr 5 info)))))
358 ;; the point-entered property doesn't seem to work in overlays
359 ;;(overlay-put ovl 'point-entered
360 ;; `(lambda (x y) (git-blame-identify ,hash)))
361 (let ((modified (buffer-modified-p)))
362 (put-text-property (if (= start 1) start (1- start)) (1- end)
363 'point-entered
364 `(lambda (x y) (git-blame-identify ,hash)))
365 (set-buffer-modified-p modified))))
366 (setq num-lines (1- num-lines))))))
367
368 (defun git-blame-add-info (key value)
369 (if git-blame-current
370 (nconc git-blame-current (list (cons (intern key) value)))))
371
372 (defun git-blame-current-commit ()
373 (let ((info (get-char-property (point) 'git-blame)))
374 (if info
375 (car info)
376 (error "No commit info"))))
377
378 (defun git-describe-commit (hash)
379 (with-temp-buffer
380 (call-process "git" nil t nil
381 "log" "-1"
382 (concat "--pretty=" git-blame-log-oneline-format)
383 hash)
384 (buffer-substring (point-min) (point-max))))
385
386 (defvar git-blame-last-identification nil)
387 (make-variable-buffer-local 'git-blame-last-identification)
388 (defun git-blame-identify (&optional hash)
389 (interactive)
390 (let ((info (gethash (or hash (git-blame-current-commit)) git-blame-cache)))
391 (when (and info (not (eq info git-blame-last-identification)))
392 (message "%s" (nth 4 info))
393 (setq git-blame-last-identification info))))
394
395 ;; (defun git-blame-after-save ()
396 ;; (when git-blame-mode
397 ;; (git-blame-cleanup)
398 ;; (git-blame-run)))
399 ;; (add-hook 'after-save-hook 'git-blame-after-save)
400
401 (defun git-blame-after-change (start end length)
402 (when git-blame-mode
403 (git-blame-enq-update start end)))
404
405 (defvar git-blame-last-update nil)
406 (make-variable-buffer-local 'git-blame-last-update)
407 (defun git-blame-enq-update (start end)
408 "Mark the region between START and END as needing blame update"
409 ;; Try to be smart and avoid multiple callouts for sequential
410 ;; editing
411 (cond ((and git-blame-last-update
412 (= start (cdr git-blame-last-update)))
413 (setcdr git-blame-last-update end))
414 ((and git-blame-last-update
415 (= end (car git-blame-last-update)))
416 (setcar git-blame-last-update start))
417 (t
418 (setq git-blame-last-update (cons start end))
419 (setq git-blame-update-queue (nconc git-blame-update-queue
420 (list git-blame-last-update)))))
421 (unless (or git-blame-proc git-blame-idle-timer)
422 (setq git-blame-idle-timer
423 (run-with-idle-timer 0.5 nil 'git-blame-delayed-update))))
424
425 (defun git-blame-delayed-update ()
426 (setq git-blame-idle-timer nil)
427 (if git-blame-update-queue
428 (let ((first (pop git-blame-update-queue))
429 (inhibit-point-motion-hooks t))
430 (git-blame-update-region (car first) (cdr first)))))
431
432 (provide 'git-blame)
433
434 ;;; git-blame.el ends here