1 ;;; git-blame.el --- Minor mode for incremental blame for Git -*- coding: utf-8 -*-
3 ;; Copyright (C) 2007 David Kågedal
5 ;; Authors: David Kågedal <davidk@lysator.liu.se>
6 ;; Created: 31 Jan 2007
7 ;; Message-ID: <87iren2vqx.fsf@morpheus.local>
9 ;; Keywords: git, version control, release management
11 ;; Compatibility: Emacs21, Emacs22 and EmacsCVS
14 ;; This file is *NOT* part of GNU Emacs.
15 ;; This file is distributed under the same terms as GNU Emacs.
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.
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.
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,
32 ;; http://www.fsf.org/copyleft/gpl.html
35 ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
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.
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:
51 ;; (require 'git-blame)
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
57 ;; (autoload 'git-blame-mode "git-blame"
58 ;; "Minor mode for incremental blame for Git." t)
60 ;; Then first use of `M-x git-blame-mode' would load the package.
64 ;; It requires GNU Emacs 21 or later and Git 1.5.0 and up
66 ;; If you'are using Emacs 20, try changing this:
68 ;; (overlay-put ovl 'face (list :background
69 ;; (cdr (assq 'color (cddddr info)))))
73 ;; (overlay-put ovl 'face (cons 'background-color
74 ;; (cdr (assq 'color (cddddr info)))))
77 ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
81 (eval-when-compile (require 'cl)) ; to use `push', `pop'
82 (require 'format-spec)
84 (defface git-blame-prefix-face
85 '((((background dark)) (:foreground "gray"
87 (((background light)) (:foreground "gray"
90 "The face used for the hash prefix."
93 (defgroup git-blame nil
94 "A minor mode showing Git blame information."
96 :link '(function-link git-blame-mode))
99 (defcustom git-blame-use-colors t
100 "Use colors to indicate commits in `git-blame-mode'."
104 (defcustom git-blame-prefix-format
106 "The format of the prefix added to each line in `git-blame'
107 mode. The format is passed to `format-spec' with the following format keys:
109 %h - the abbreviated hash
112 %A - the author email
113 %c - the committer name
114 %C - the committer email
115 %s - the commit summary
119 (defcustom git-blame-mouseover-format
121 "The format of the description shown when pointing at a line in
122 `git-blame' mode. The format string is passed to `format-spec'
123 with the following format keys:
125 %h - the abbreviated hash
128 %A - the author email
129 %c - the committer name
130 %C - the committer email
131 %s - the commit summary
136 (defun git-blame-color-scale (&rest elements)
137 "Given a list, returns a list of triples formed with each
138 elements of the list.
140 a b => bbb bba bab baa abb aba aaa aab"
145 (setq result (cons (format "#%s%s%s" a b c) result)))))
148 ;; (git-blame-color-scale "0c" "04" "24" "1c" "2c" "34" "14" "3c") =>
149 ;; ("#3c3c3c" "#3c3c14" "#3c3c34" "#3c3c2c" "#3c3c1c" "#3c3c24"
150 ;; "#3c3c04" "#3c3c0c" "#3c143c" "#3c1414" "#3c1434" "#3c142c" ...)
152 (defmacro git-blame-random-pop (l)
153 "Select a random element from L and returns it. Also remove
154 selected element from l."
155 ;; only works on lists with unique elements
156 `(let ((e (elt ,l (random (length ,l)))))
157 (setq ,l (remove e ,l))
160 (defvar git-blame-log-oneline-format
161 "format:[%cr] %cn: %s"
162 "*Formatting option used for describing current line in the minibuffer.
164 This option is used to pass to git log --pretty= command-line option,
165 and describe which commit the current line was made.")
167 (defvar git-blame-dark-colors
168 (git-blame-color-scale "0c" "04" "24" "1c" "2c" "34" "14" "3c")
169 "*List of colors (format #RGB) to use in a dark environment.
171 To check out the list, evaluate (list-colors-display git-blame-dark-colors).")
173 (defvar git-blame-light-colors
174 (git-blame-color-scale "c4" "d4" "cc" "dc" "f4" "e4" "fc" "ec")
175 "*List of colors (format #RGB) to use in a light environment.
177 To check out the list, evaluate (list-colors-display git-blame-light-colors).")
179 (defvar git-blame-colors '()
180 "Colors used by git-blame. The list is built once when activating git-blame
183 (defvar git-blame-ancient-color "dark green"
184 "*Color to be used for ancient commit.")
186 (defvar git-blame-autoupdate t
187 "*Automatically update the blame display while editing")
189 (defvar git-blame-proc nil
190 "The running git-blame process")
191 (make-variable-buffer-local 'git-blame-proc)
193 (defvar git-blame-overlays nil
194 "The git-blame overlays used in the current buffer.")
195 (make-variable-buffer-local 'git-blame-overlays)
197 (defvar git-blame-cache nil
198 "A cache of git-blame information for the current buffer")
199 (make-variable-buffer-local 'git-blame-cache)
201 (defvar git-blame-idle-timer nil
202 "An idle timer that updates the blame")
203 (make-variable-buffer-local 'git-blame-cache)
205 (defvar git-blame-update-queue nil
206 "A queue of update requests")
207 (make-variable-buffer-local 'git-blame-update-queue)
210 (defvar git-blame-file nil)
211 (defvar git-blame-current nil)
213 (defvar git-blame-mode nil)
214 (make-variable-buffer-local 'git-blame-mode)
216 (defvar git-blame-mode-line-string " blame"
217 "String to display on the mode line when git-blame is active.")
219 (or (assq 'git-blame-mode minor-mode-alist)
220 (setq minor-mode-alist
221 (cons '(git-blame-mode git-blame-mode-line-string) minor-mode-alist)))
224 (defun git-blame-mode (&optional arg)
225 "Toggle minor mode for displaying Git blame
227 With prefix ARG, turn the mode on if ARG is positive."
231 (if git-blame-mode (git-blame-mode-off) (git-blame-mode-on)))
232 ((> (prefix-numeric-value arg) 0) (git-blame-mode-on))
233 (t (git-blame-mode-off))))
235 (defun git-blame-mode-on ()
236 "Turn on git-blame mode.
238 See also function `git-blame-mode'."
239 (make-local-variable 'git-blame-colors)
240 (if git-blame-autoupdate
241 (add-hook 'after-change-functions 'git-blame-after-change nil t)
242 (remove-hook 'after-change-functions 'git-blame-after-change t))
244 (let ((bgmode (cdr (assoc 'background-mode (frame-parameters)))))
245 (if (eq bgmode 'dark)
246 (setq git-blame-colors git-blame-dark-colors)
247 (setq git-blame-colors git-blame-light-colors)))
248 (setq git-blame-cache (make-hash-table :test 'equal))
249 (setq git-blame-mode t)
252 (defun git-blame-mode-off ()
253 "Turn off git-blame mode.
255 See also function `git-blame-mode'."
257 (if git-blame-idle-timer (cancel-timer git-blame-idle-timer))
258 (setq git-blame-mode nil))
261 (defun git-reblame ()
262 "Recalculate all blame information in the current buffer"
264 (unless git-blame-mode
265 (error "Git-blame is not active"))
270 (defun git-blame-run (&optional startline endline)
272 ;; Should maybe queue up a new run here
273 (message "Already running git blame")
274 (let ((display-buf (current-buffer))
275 (blame-buf (get-buffer-create
276 (concat " git blame for " (buffer-name))))
277 (args '("--incremental" "--contents" "-")))
279 (setq args (append args
280 (list "-L" (format "%d,%d" startline endline)))))
281 (setq args (append args
282 (list (file-name-nondirectory buffer-file-name))))
284 (apply 'start-process
285 "git-blame" blame-buf
288 (with-current-buffer blame-buf
290 (make-local-variable 'git-blame-file)
291 (make-local-variable 'git-blame-current)
292 (setq git-blame-file display-buf)
293 (setq git-blame-current nil))
294 (set-process-filter git-blame-proc 'git-blame-filter)
295 (set-process-sentinel git-blame-proc 'git-blame-sentinel)
296 (process-send-region git-blame-proc (point-min) (point-max))
297 (process-send-eof git-blame-proc))))
299 (defun remove-git-blame-text-properties (start end)
300 (let ((modified (buffer-modified-p))
301 (inhibit-read-only t))
302 (remove-text-properties start end '(point-entered nil))
303 (set-buffer-modified-p modified)))
305 (defun git-blame-cleanup ()
306 "Remove all blame properties"
307 (mapcar 'delete-overlay git-blame-overlays)
308 (setq git-blame-overlays nil)
309 (remove-git-blame-text-properties (point-min) (point-max)))
311 (defun git-blame-update-region (start end)
312 "Rerun blame to get updates between START and END"
313 (let ((overlays (overlays-in start end)))
315 (let ((overlay (pop overlays)))
316 (if (< (overlay-start overlay) start)
317 (setq start (overlay-start overlay)))
318 (if (> (overlay-end overlay) end)
319 (setq end (overlay-end overlay)))
320 (setq git-blame-overlays (delete overlay git-blame-overlays))
321 (delete-overlay overlay))))
322 (remove-git-blame-text-properties start end)
323 ;; We can be sure that start and end are at line breaks
324 (git-blame-run (1+ (count-lines (point-min) start))
325 (count-lines (point-min) end)))
327 (defun git-blame-sentinel (proc status)
328 (with-current-buffer (process-buffer proc)
329 (with-current-buffer git-blame-file
330 (setq git-blame-proc nil)
331 (if git-blame-update-queue
332 (git-blame-delayed-update))))
333 ;;(kill-buffer (process-buffer proc))
334 ;;(message "git blame finished")
337 (defvar in-blame-filter nil)
339 (defun git-blame-filter (proc str)
341 (set-buffer (process-buffer proc))
342 (goto-char (process-mark proc))
343 (insert-before-markers str)
345 (unless in-blame-filter
349 (setq more (git-blame-parse)))))))
351 (defun git-blame-parse ()
352 (cond ((looking-at "\\([0-9a-f]\\{40\\}\\) \\([0-9]+\\) \\([0-9]+\\) \\([0-9]+\\)\n")
353 (let ((hash (match-string 1))
354 (src-line (string-to-number (match-string 2)))
355 (res-line (string-to-number (match-string 3)))
356 (num-lines (string-to-number (match-string 4))))
357 (delete-region (point) (match-end 0))
358 (setq git-blame-current (list (git-blame-new-commit hash)
359 src-line res-line num-lines)))
361 ((looking-at "\\([a-z-]+\\) \\(.+\\)\n")
362 (let ((key (match-string 1))
363 (value (match-string 2)))
364 (delete-region (point) (match-end 0))
365 (git-blame-add-info (car git-blame-current) key value)
366 (when (string= key "filename")
367 (git-blame-create-overlay (car git-blame-current)
368 (caddr git-blame-current)
369 (cadddr git-blame-current))
370 (setq git-blame-current nil)))
375 (defun git-blame-new-commit (hash)
376 (with-current-buffer git-blame-file
377 (or (gethash hash git-blame-cache)
378 ;; Assign a random color to each new commit info
379 ;; Take care not to select the same color multiple times
380 (let* ((color (if git-blame-colors
381 (git-blame-random-pop git-blame-colors)
382 git-blame-ancient-color))
383 (info `(,hash (color . ,color))))
384 (puthash hash info git-blame-cache)
387 (defun git-blame-create-overlay (info start-line num-lines)
389 (set-buffer git-blame-file)
390 (let ((inhibit-point-motion-hooks t)
391 (inhibit-modification-hooks t))
392 (goto-line start-line)
393 (let* ((start (point))
394 (end (progn (forward-line num-lines) (point)))
395 (ovl (make-overlay start end))
397 (spec `((?h . ,(substring hash 0 6))
399 (?a . ,(git-blame-get-info info 'author))
400 (?A . ,(git-blame-get-info info 'author-mail))
401 (?c . ,(git-blame-get-info info 'committer))
402 (?C . ,(git-blame-get-info info 'committer-mail))
403 (?s . ,(git-blame-get-info info 'summary)))))
404 (push ovl git-blame-overlays)
405 (overlay-put ovl 'git-blame info)
406 (overlay-put ovl 'help-echo
407 (format-spec git-blame-mouseover-format spec))
408 (if git-blame-use-colors
409 (overlay-put ovl 'face (list :background
410 (cdr (assq 'color (cdr info))))))
411 (overlay-put ovl 'line-prefix
412 (propertize (format-spec git-blame-prefix-format spec)
413 'face 'git-blame-prefix-face))))))
415 (defun git-blame-add-info (info key value)
416 (nconc info (list (cons (intern key) value))))
418 (defun git-blame-get-info (info key)
419 (cdr (assq key (cdr info))))
421 (defun git-blame-current-commit ()
422 (let ((info (get-char-property (point) 'git-blame)))
425 (error "No commit info"))))
427 (defun git-describe-commit (hash)
429 (call-process "git" nil t nil
431 (concat "--pretty=" git-blame-log-oneline-format)
433 (buffer-substring (point-min) (point-max))))
435 (defvar git-blame-last-identification nil)
436 (make-variable-buffer-local 'git-blame-last-identification)
437 (defun git-blame-identify (&optional hash)
439 (let ((info (gethash (or hash (git-blame-current-commit)) git-blame-cache)))
440 (when (and info (not (eq info git-blame-last-identification)))
441 (message "%s" (nth 4 info))
442 (setq git-blame-last-identification info))))
444 ;; (defun git-blame-after-save ()
445 ;; (when git-blame-mode
446 ;; (git-blame-cleanup)
448 ;; (add-hook 'after-save-hook 'git-blame-after-save)
450 (defun git-blame-after-change (start end length)
452 (git-blame-enq-update start end)))
454 (defvar git-blame-last-update nil)
455 (make-variable-buffer-local 'git-blame-last-update)
456 (defun git-blame-enq-update (start end)
457 "Mark the region between START and END as needing blame update"
458 ;; Try to be smart and avoid multiple callouts for sequential
460 (cond ((and git-blame-last-update
461 (= start (cdr git-blame-last-update)))
462 (setcdr git-blame-last-update end))
463 ((and git-blame-last-update
464 (= end (car git-blame-last-update)))
465 (setcar git-blame-last-update start))
467 (setq git-blame-last-update (cons start end))
468 (setq git-blame-update-queue (nconc git-blame-update-queue
469 (list git-blame-last-update)))))
470 (unless (or git-blame-proc git-blame-idle-timer)
471 (setq git-blame-idle-timer
472 (run-with-idle-timer 0.5 nil 'git-blame-delayed-update))))
474 (defun git-blame-delayed-update ()
475 (setq git-blame-idle-timer nil)
476 (if git-blame-update-queue
477 (let ((first (pop git-blame-update-queue))
478 (inhibit-point-motion-hooks t))
479 (git-blame-update-region (car first) (cdr first)))))
483 ;;; git-blame.el ends here