contrib/emacs/vc-git.el - jrn/git - Git at Google

 ;;; vc-git.el --- VC backend for the git version control system

 ;; Copyright (C) 2006 Alexandre Julliard

 ;; This program is free software; you can redistribute it and/or
 ;; modify it under the terms of the GNU General Public License as
 ;; published by the Free Software Foundation; either version 2 of
 ;; the License, or (at your option) any later version.
 ;;
 ;; This program is distributed in the hope that it will be
 ;; useful, but WITHOUT ANY WARRANTY; without even the implied
 ;; warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR
 ;; PURPOSE.  See the GNU General Public License for more details.
 ;;
 ;; You should have received a copy of the GNU General Public
 ;; License along with this program; if not, write to the Free
 ;; Software Foundation, Inc., 59 Temple Place, Suite 330, Boston,
 ;; MA 02111-1307 USA

 ;;; Commentary:

 ;; This file contains a VC backend for the git version control
 ;; system.
 ;;
 ;; To install: put this file on the load-path and add GIT to the list
 ;; of supported backends in `vc-handled-backends'; the following line,
 ;; placed in your ~/.emacs, will accomplish this:
 ;;
 ;;     (add-to-list 'vc-handled-backends 'GIT)
 ;;
 ;; TODO
 ;;  - changelog generation
 ;;  - working with revisions other than HEAD
 ;;

 (eval-when-compile (require 'cl))

 (defvar git-commits-coding-system 'utf-8
   "Default coding system for git commits.")

 (defun vc-git--run-command-string (file &rest args)
   "Run a git command on FILE and return its output as string."
   (let* ((ok t)
          (str (with-output-to-string
                 (with-current-buffer standard-output
                   (unless (eq 0 (apply #'call-process "git" nil '(t nil) nil
                                        (append args (list (file-relative-name file)))))
                     (setq ok nil))))))
     (and ok str)))

 (defun vc-git--run-command (file &rest args)
   "Run a git command on FILE, discarding any output."
   (let ((name (file-relative-name file)))
     (eq 0 (apply #'call-process "git" nil (get-buffer "*Messages") nil (append args (list name))))))

 (defun vc-git-registered (file)
   "Check whether FILE is registered with git."
   (with-temp-buffer
     (let* ((dir (file-name-directory file))
            (name (file-relative-name file dir)))
       (and (ignore-errors
              (when dir (cd dir))
              (eq 0 (call-process "git" nil '(t nil) nil "ls-files" "-c" "-z" "--" name)))
            (let ((str (buffer-string)))
              (and (> (length str) (length name))
                   (string= (substring str 0 (1+ (length name))) (concat name "\0"))))))))

 (defun vc-git-state (file)
   "git-specific version of `vc-state'."
   (let ((diff (vc-git--run-command-string file "diff-index" "-z" "HEAD" "--")))
     (if (and diff (string-match ":[0-7]\\{6\\} [0-7]\\{6\\} [0-9a-f]\\{40\\} [0-9a-f]\\{40\\} [ADMU]\0[^\0]+\0" diff))
         'edited
       'up-to-date)))

 (defun vc-git-workfile-version (file)
   "git-specific version of `vc-workfile-version'."
   (let ((str (with-output-to-string
                (with-current-buffer standard-output
                  (call-process "git" nil '(t nil) nil "symbolic-ref" "HEAD")))))
     (if (string-match "^\\(refs/heads/\\)?\\(.+\\)$" str)
         (match-string 2 str)
       str)))

 (defun vc-git-revert (file &optional contents-done)
   "Revert FILE to the version stored in the git repository."
   (if contents-done
       (vc-git--run-command file "update-index" "--")
     (vc-git--run-command file "checkout" "HEAD")))

 (defun vc-git-checkout-model (file)
   'implicit)

 (defun vc-git-workfile-unchanged-p (file)
   (let ((sha1 (vc-git--run-command-string file "hash-object" "--"))
         (head (vc-git--run-command-string file "ls-tree" "-z" "HEAD" "--")))
     (and head
          (string-match "[0-7]\\{6\\} blob \\([0-9a-f]\\{40\\}\\)\t[^\0]+\0" head)
          (string= (car (split-string sha1 "\n")) (match-string 1 head)))))

 (defun vc-git-register (file &optional rev comment)
   "Register FILE into the git version-control system."
   (vc-git--run-command file "update-index" "--add" "--"))

 (defun vc-git-print-log (file &optional buffer)
   (let ((name (file-relative-name file))
         (coding-system-for-read git-commits-coding-system))
     (vc-do-command buffer 'async "git" name "rev-list" "--pretty" "HEAD" "--")))

 (defun vc-git-diff (file &optional rev1 rev2 buffer)
   (let ((name (file-relative-name file))
         (buf (or buffer "*vc-diff*")))
     (if (and rev1 rev2)
         (vc-do-command buf 0 "git" name "diff-tree" "-p" rev1 rev2 "--")
       (vc-do-command buf 0 "git" name "diff-index" "-p" (or rev1 "HEAD") "--"))
     ; git-diff-index doesn't set exit status like diff does
     (if (vc-git-workfile-unchanged-p file) 0 1)))

 (defun vc-git-checkin (file rev comment)
   (let ((coding-system-for-write git-commits-coding-system))
     (vc-git--run-command file "commit" "-m" comment "--only" "--")))

 (defun vc-git-checkout (file &optional editable rev destfile)
   (if destfile
       (let ((fullname (substring
                        (vc-git--run-command-string file "ls-files" "-z" "--full-name" "--")
                        0 -1))
             (coding-system-for-read 'no-conversion)
             (coding-system-for-write 'no-conversion))
         (with-temp-file destfile
           (eq 0 (call-process "git" nil t nil "cat-file" "blob"
                               (concat (or rev "HEAD") ":" fullname)))))
     (vc-git--run-command file "checkout" (or rev "HEAD"))))

 (defun vc-git-annotate-command (file buf &optional rev)
   ; FIXME: rev is ignored
   (let ((name (file-relative-name file)))
     (call-process "git" nil buf nil "blame" name)))

 (defun vc-git-annotate-time ()
   (and (re-search-forward "[0-9a-f]+ (.* \\([0-9]+\\)-\\([0-9]+\\)-\\([0-9]+\\) \\([0-9]+\\):\\([0-9]+\\):\\([0-9]+\\) \\([-+0-9]+\\) +[0-9]+)" nil t)
        (vc-annotate-convert-time
         (apply #'encode-time (mapcar (lambda (match) (string-to-number (match-string match))) '(6 5 4 3 2 1 7))))))

 ;; Not really useful since we can't do anything with the revision yet
 ;;(defun vc-annotate-extract-revision-at-line ()
 ;;  (save-excursion
 ;;    (move-beginning-of-line 1)
 ;;    (and (looking-at "[0-9a-f]+")
 ;;         (buffer-substring (match-beginning 0) (match-end 0)))))

 (provide 'vc-git)
	;;; vc-git.el --- VC backend for the git version control system

	;; Copyright (C) 2006 Alexandre Julliard

	;; This program is free software; you can redistribute it and/or
	;; modify it under the terms of the GNU General Public License as
	;; published by the Free Software Foundation; either version 2 of
	;; the License, or (at your option) any later version.
	;;
	;; This program is distributed in the hope that it will be
	;; useful, but WITHOUT ANY WARRANTY; without even the implied
	;; warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR
	;; PURPOSE. See the GNU General Public License for more details.
	;;
	;; You should have received a copy of the GNU General Public
	;; License along with this program; if not, write to the Free
	;; Software Foundation, Inc., 59 Temple Place, Suite 330, Boston,
	;; MA 02111-1307 USA

	;;; Commentary:

	;; This file contains a VC backend for the git version control
	;; system.
	;;
	;; To install: put this file on the load-path and add GIT to the list
	;; of supported backends in `vc-handled-backends'; the following line,
	;; placed in your ~/.emacs, will accomplish this:
	;;
	;; (add-to-list 'vc-handled-backends 'GIT)
	;;
	;; TODO
	;; - changelog generation
	;; - working with revisions other than HEAD
	;;

	(eval-when-compile (require 'cl))

	(defvar git-commits-coding-system 'utf-8
	"Default coding system for git commits.")

	(defun vc-git--run-command-string (file &rest args)
	"Run a git command on FILE and return its output as string."
	(let* ((ok t)
	(str (with-output-to-string
	(with-current-buffer standard-output
	(unless (eq 0 (apply #'call-process "git" nil '(t nil) nil
	(append args (list (file-relative-name file)))))
	(setq ok nil))))))
	(and ok str)))

	(defun vc-git--run-command (file &rest args)
	"Run a git command on FILE, discarding any output."
	(let ((name (file-relative-name file)))
	(eq 0 (apply #'call-process "git" nil (get-buffer "*Messages") nil (append args (list name))))))

	(defun vc-git-registered (file)
	"Check whether FILE is registered with git."
	(with-temp-buffer
	(let* ((dir (file-name-directory file))
	(name (file-relative-name file dir)))
	(and (ignore-errors
	(when dir (cd dir))
	(eq 0 (call-process "git" nil '(t nil) nil "ls-files" "-c" "-z" "--" name)))
	(let ((str (buffer-string)))
	(and (> (length str) (length name))
	(string= (substring str 0 (1+ (length name))) (concat name "\0"))))))))

	(defun vc-git-state (file)
	"git-specific version of `vc-state'."
	(let ((diff (vc-git--run-command-string file "diff-index" "-z" "HEAD" "--")))
	(if (and diff (string-match ":[0-7]\\{6\\} [0-7]\\{6\\} [0-9a-f]\\{40\\} [0-9a-f]\\{40\\} [ADMU]\0[^\0]+\0" diff))
	'edited
	'up-to-date)))

	(defun vc-git-workfile-version (file)
	"git-specific version of `vc-workfile-version'."
	(let ((str (with-output-to-string
	(with-current-buffer standard-output
	(call-process "git" nil '(t nil) nil "symbolic-ref" "HEAD")))))
	(if (string-match "^\\(refs/heads/\\)?\\(.+\\)$" str)
	(match-string 2 str)
	str)))

	(defun vc-git-revert (file &optional contents-done)
	"Revert FILE to the version stored in the git repository."
	(if contents-done
	(vc-git--run-command file "update-index" "--")
	(vc-git--run-command file "checkout" "HEAD")))

	(defun vc-git-checkout-model (file)
	'implicit)

	(defun vc-git-workfile-unchanged-p (file)
	(let ((sha1 (vc-git--run-command-string file "hash-object" "--"))
	(head (vc-git--run-command-string file "ls-tree" "-z" "HEAD" "--")))
	(and head
	(string-match "[0-7]\\{6\\} blob \\([0-9a-f]\\{40\\}\\)\t[^\0]+\0" head)
	(string= (car (split-string sha1 "\n")) (match-string 1 head)))))

	(defun vc-git-register (file &optional rev comment)
	"Register FILE into the git version-control system."
	(vc-git--run-command file "update-index" "--add" "--"))

	(defun vc-git-print-log (file &optional buffer)
	(let ((name (file-relative-name file))
	(coding-system-for-read git-commits-coding-system))
	(vc-do-command buffer 'async "git" name "rev-list" "--pretty" "HEAD" "--")))

	(defun vc-git-diff (file &optional rev1 rev2 buffer)
	(let ((name (file-relative-name file))
	(buf (or buffer "vc-diff")))
	(if (and rev1 rev2)
	(vc-do-command buf 0 "git" name "diff-tree" "-p" rev1 rev2 "--")
	(vc-do-command buf 0 "git" name "diff-index" "-p" (or rev1 "HEAD") "--"))
	; git-diff-index doesn't set exit status like diff does
	(if (vc-git-workfile-unchanged-p file) 0 1)))

	(defun vc-git-checkin (file rev comment)
	(let ((coding-system-for-write git-commits-coding-system))
	(vc-git--run-command file "commit" "-m" comment "--only" "--")))

	(defun vc-git-checkout (file &optional editable rev destfile)
	(if destfile
	(let ((fullname (substring
	(vc-git--run-command-string file "ls-files" "-z" "--full-name" "--")
	0 -1))
	(coding-system-for-read 'no-conversion)
	(coding-system-for-write 'no-conversion))
	(with-temp-file destfile
	(eq 0 (call-process "git" nil t nil "cat-file" "blob"
	(concat (or rev "HEAD") ":" fullname)))))
	(vc-git--run-command file "checkout" (or rev "HEAD"))))

	(defun vc-git-annotate-command (file buf &optional rev)
	; FIXME: rev is ignored
	(let ((name (file-relative-name file)))
	(call-process "git" nil buf nil "blame" name)))

	(defun vc-git-annotate-time ()
	(and (re-search-forward "[0-9a-f]+ (.* \\([0-9]+\\)-\\([0-9]+\\)-\\([0-9]+\\) \\([0-9]+\\):\\([0-9]+\\):\\([0-9]+\\) \\([-+0-9]+\\) +[0-9]+)" nil t)
	(vc-annotate-convert-time
	(apply #'encode-time (mapcar (lambda (match) (string-to-number (match-string match))) '(6 5 4 3 2 1 7))))))

	;; Not really useful since we can't do anything with the revision yet
	;;(defun vc-annotate-extract-revision-at-line ()
	;; (save-excursion
	;; (move-beginning-of-line 1)
	;; (and (looking-at "[0-9a-f]+")
	;; (buffer-substring (match-beginning 0) (match-end 0)))))

	(provide 'vc-git)