[bpt/emacs.git] / lisp / vc-bzr.el

;;; vc-bzr.el --- VC backend for the bzr revision control system

;; Copyright (C) 2006, 2007  Free Software Foundation, Inc.

;; Author: Dave Love <fx@gnu.org>, Riccardo Murri <riccardo.murri@gmail.com>
;; Keywords: tools
;; Created: Sept 2006
;; Version: 2007-08-03
;; URL: http://launchpad.net/vc-bzr

;; This file 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 3, or (at your option)
;; any later version.

;; This file 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 GNU Emacs; see the file COPYING.  If not, write to the
;; Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
;; Boston, MA 02110-1301, USA.


;;; Commentary:

;; See <URL:http://bazaar-vcs.org/> concerning bzr.

;; Load this library to register bzr support in VC.  It covers basic VC 
;; functionality, but was only lightly exercised with a few Emacs/bzr
;; version combinations, namely those current on the authors' PCs.
;; See various Fixmes below.


;; Known bugs
;; ==========

;; When edititing a symlink and *both* the symlink and its target
;; are bzr-versioned, `vc-bzr` presently runs `bzr status` on the
;; symlink, thereby not detecting whether the actual contents
;; (that is, the target contents) are changed.  
;; See https://bugs.launchpad.net/vc-bzr/+bug/116607

;; For an up-to-date list of bugs, please see:
;;   https://bugs.launchpad.net/vc-bzr/+bugs


;;; Code:

(eval-when-compile
  (require 'cl)
  (require 'vc))                        ; for vc-exec-after

;; Clear up the cache to force vc-call to check again and discover
;; new functions when we reload this file.
(put 'Bzr 'vc-functions nil)

(defgroup vc-bzr nil
  "VC bzr backend."
;;   :version "22"
  :group 'vc)

(defcustom vc-bzr-program "bzr"
  "Name of the bzr command (excluding any arguments)."
  :group 'vc-bzr
  :type 'string)

;; Fixme: there's probably no call for this.
(defcustom vc-bzr-program-args nil
  "List of global arguments to pass to `vc-bzr-program'."
  :group 'vc-bzr
  :type '(repeat string))

(defcustom vc-bzr-diff-switches nil
  "String/list of strings specifying extra switches for bzr diff under VC."
  :type '(choice (const :tag "None" nil)
                 (string :tag "Argument String")
                 (repeat :tag "Argument List" :value ("") string))
  :group 'vc-bzr)

;; since v0.9, bzr supports removing the progress indicators
;; by setting environment variable BZR_PROGRESS_BAR to "none".
(defun vc-bzr-command (bzr-command buffer okstatus file-or-list &rest args)
  "Wrapper round `vc-do-command' using `vc-bzr-program' as COMMAND.
Invoke the bzr command adding `BZR_PROGRESS_BAR=none' to the environment."
  (let ((process-environment
         (list* "BZR_PROGRESS_BAR=none" ; Suppress progress output (bzr >=0.9)
                "LC_ALL=C"              ; Force English output
                process-environment)))
    (apply 'vc-do-command buffer okstatus vc-bzr-program
           file-or-list bzr-command (append vc-bzr-program-args args))))

;;;###autoload
(defconst vc-bzr-admin-dirname ".bzr"    ; FIXME: "_bzr" on w32?
  "Name of the directory containing Bzr repository status files.")
;;;###autoload
(defconst vc-bzr-admin-checkout-format-file
  (concat vc-bzr-admin-dirname "/checkout/format"))
(defconst vc-bzr-admin-dirstate
  (concat vc-bzr-admin-dirname "/checkout/dirstate"))
(defconst vc-bzr-admin-branch-format-file
  (concat vc-bzr-admin-dirname "/branch/format"))
(defconst vc-bzr-admin-revhistory
  (concat vc-bzr-admin-dirname "/branch/revision-history"))

;;;###autoload (defun vc-bzr-registered (file)
;;;###autoload   (if (vc-find-root file vc-bzr-admin-checkout-format-file)
;;;###autoload       (progn
;;;###autoload         (load "vc-bzr")
;;;###autoload         (vc-bzr-registered file))))

(defun vc-bzr-root (file)
  "Return the root directory of the bzr repository containing FILE."
  ;; Cache technique copied from vc-arch.el.
  (or (vc-file-getprop file 'bzr-root)
      (vc-file-setprop
       file 'bzr-root
       (vc-find-root file vc-bzr-admin-checkout-format-file))))

(defun vc-bzr-registered (file)
  "Return non-nil if FILE is registered with bzr.

For speed, this function tries first to parse Bzr internal file
`checkout/dirstate', but it may fail if Bzr internal file format
has changed.  As a safeguard, the `checkout/dirstate' file is
only parsed if it contains the string `#bazaar dirstate flat
format 3' in the first line.

If the `checkout/dirstate' file cannot be parsed, fall back to
running `vc-bzr-state'."
  (condition-case nil
      (lexical-let ((root (vc-bzr-root file)))
    (and root ; Short cut.
         ;; This looks at internal files.  May break if they change
         ;; their format.
             (lexical-let
                 ((dirstate-file (expand-file-name vc-bzr-admin-dirstate root)))
               (if (file-exists-p dirstate-file)
         (with-temp-buffer
                     (insert-file-contents dirstate-file)
           (goto-char (point-min))
                     (when (looking-at "#bazaar dirstate flat format 3")
           (let* ((relfile (file-relative-name file root))
                  (reldir (file-name-directory relfile)))
             (re-search-forward
              (concat "^\0"
                      (if reldir (regexp-quote (directory-file-name reldir)))
                      "\0"
                      (regexp-quote (file-name-nondirectory relfile))
                      "\0")
                        nil t))))
                 t))
             (vc-bzr-state file)))  ; Expensive.
    (file-error nil))) ; vc-bzr-program not found

(defun vc-bzr-buffer-nonblank-p (&optional buffer)
  "Return non-nil if BUFFER contains any non-blank characters."
  (or (> (buffer-size buffer) 0)
      (save-excursion
        (set-buffer (or buffer (current-buffer)))
        (goto-char (point-min))
        (re-search-forward "[^ \t\n]" (point-max) t))))

(defconst vc-bzr-state-words
  "added\\|ignored\\|modified\\|removed\\|renamed\\|unknown"
  "Regexp matching file status words as reported in `bzr' output.")

(defun vc-bzr-file-name-relative (filename)
  "Return file name FILENAME stripped of the initial Bzr repository path."
  (lexical-let*
      ((filename* (expand-file-name filename))
       (rootdir (vc-bzr-root (file-name-directory filename*))))
    (and rootdir 
         (file-relative-name filename* rootdir))))

;; FIXME:  Also get this in a non-registered sub-directory.
(defun vc-bzr-state (file)
  (condition-case nil
  (with-temp-buffer
        (let ((ret (vc-bzr-command "status" t 0 file))
          (state 'up-to-date))
      ;; the only secure status indication in `bzr status' output
      ;; is a couple of lines following the pattern::
      ;;   | <status>:
      ;;   |   <file name>
      ;; if the file is up-to-date, we get no status report from `bzr',
      ;; so if the regexp search for the above pattern fails, we consider
      ;; the file to be up-to-date.
      (goto-char (point-min))
      (when
          (re-search-forward
               ;; bzr prints paths relative to the repository root
           (concat "^\\(" vc-bzr-state-words "\\):[ \t\n]+"
                       (regexp-quote (vc-bzr-file-name-relative file)) "[ \t\n]*$")
           (point-max) t)
        (let ((start (match-beginning 0))
              (end (match-end 0)))
          (goto-char start)
          (setq state
                (cond
                 ((not (equal ret 0)) nil)
                 ((looking-at "added\\|renamed\\|modified\\|removed") 'edited)
                 ((looking-at "unknown\\|ignored") nil)))
          ;; erase the status text that matched
          (delete-region start end)))
      (when (vc-bzr-buffer-nonblank-p)
            ;; "bzr" will output warnings and informational messages to
            ;; stderr; due to Emacs' `vc-do-command' (and, it seems,
            ;; `start-process' itself) limitations, we cannot catch stderr
        ;; and stdout into different buffers.  So, if there's anything
        ;; left in the buffer after removing the above status
        ;; keywords, let us just presume that any other message from
        ;; "bzr" is a user warning, and display it.
        (message "Warnings in `bzr' output: %s"
               (buffer-substring (point-min) (point-max))))
      (when state
        (vc-file-setprop file 'vc-workfile-version
                         (vc-bzr-workfile-version file))
        (vc-file-setprop file 'vc-state state))
          state))
    (file-error nil))) ; vc-bzr-program not found

(defun vc-bzr-workfile-unchanged-p (file)
  (eq 'up-to-date (vc-bzr-state file)))

(defun vc-bzr-workfile-version (file)
  (lexical-let*
      ((rootdir (vc-bzr-root file))
       (branch-format-file (concat rootdir "/" vc-bzr-admin-branch-format-file))
       (revhistory-file (concat rootdir "/" vc-bzr-admin-revhistory))
       (lastrev-file (concat rootdir "/" "branch/last-revision")))
    ;; Count lines in .bzr/branch/revision-history to avoid forking a
    ;; bzr process.  This looks at internal files.  May break if they
    ;; change their format.
    (if (file-exists-p branch-format-file)
  (with-temp-buffer
          (insert-file-contents branch-format-file) 
          (goto-char (point-min))
          (cond
           ((or
             (looking-at "Bazaar-NG branch, format 0.0.4")
             (looking-at "Bazaar-NG branch format 5"))
            ;; count lines in .bzr/branch/revision-history
          (insert-file-contents revhistory-file) 
            (number-to-string (count-lines (line-end-position) (point-max))))
           ((looking-at "Bazaar Branch Format 6 (bzr 0.15)")
            ;; revno is the first number in .bzr/branch/last-revision
            (insert-file-contents lastrev-file) 
            (goto-char (line-end-position))
            (if (re-search-forward "[0-9]+" nil t)
                (buffer-substring (match-beginning 0) (match-end 0))))))
      ;; fallback to calling "bzr revno"
      (lexical-let*
          ((result (vc-bzr-command-discarding-stderr
                    vc-bzr-program "revno" file))
           (exitcode (car result))
           (output (cdr result)))
        (cond
         ((eq exitcode 0) (substring output 0 -1))
         (t nil))))))

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

(defun vc-bzr-create-repo ()
  "Create a new Bzr repository."
  (vc-bzr-command "init" nil 0 nil))

(defun vc-bzr-register (files &optional rev comment)
  "Register FILE under bzr.
Signal an error unless REV is nil.
COMMENT is ignored."
  (if rev (error "Can't register explicit version with bzr"))
  (vc-bzr-command "add" nil 0 files))

;; Could run `bzr status' in the directory and see if it succeeds, but
;; that's relatively expensive.
(defalias 'vc-bzr-responsible-p 'vc-bzr-root
  "Return non-nil if FILE is (potentially) controlled by bzr.
The criterion is that there is a `.bzr' directory in the same
or a superior directory.")

(defun vc-bzr-could-register (file)
  "Return non-nil if FILE could be registered under bzr."
  (and (vc-bzr-responsible-p file)      ; shortcut
       (condition-case ()
           (with-temp-buffer
             (vc-bzr-command "add" t 0 file "--dry-run")
             ;; The command succeeds with no output if file is
             ;; registered (in bzr 0.8).
             (goto-char (point-min))
             (looking-at "added "))
         (error))))

(defun vc-bzr-unregister (file)
  "Unregister FILE from bzr."
  (vc-bzr-command "remove" nil 0 file))

(defun vc-bzr-checkin (files rev comment)
  "Check FILE in to bzr with log message COMMENT.
REV non-nil gets an error."
  (if rev (error "Can't check in a specific version with bzr"))
  (vc-bzr-command "commit" nil 0 files "-m" comment))

(defun vc-bzr-checkout (file &optional editable rev destfile)
  "Checkout revision REV of FILE from bzr to DESTFILE.
EDITABLE is ignored."
  (unless destfile
    (setq destfile (vc-version-backup-file-name file rev)))
  (let ((coding-system-for-read 'binary)
        (coding-system-for-write 'binary))
  (with-temp-file destfile
    (if rev
        (vc-bzr-command "cat" t 0 file "-r" rev)
      (vc-bzr-command "cat" t 0 file)))))

(defun vc-bzr-revert (file &optional contents-done)
  (unless contents-done
    (with-temp-buffer (vc-bzr-command "revert" t 'async file))))

(defvar log-view-message-re)
(defvar log-view-file-re)
(defvar log-view-font-lock-keywords)
(defvar log-view-current-tag-function)

(define-derived-mode vc-bzr-log-view-mode log-view-mode "Bzr-Log-View"
  (remove-hook 'log-view-mode-hook 'vc-bzr-log-view-mode) ;Deactivate the hack.
  (require 'add-log)
  ;; Don't have file markers, so use impossible regexp.
  (set (make-local-variable 'log-view-file-re) "\\'\\`")
  (set (make-local-variable 'log-view-message-re)
       "^ *-+\n *\\(?:revno: \\([0-9]+\\)\\|merged: .+\\)")
  (set (make-local-variable 'log-view-font-lock-keywords)
       ;; log-view-font-lock-keywords is careful to use the buffer-local
       ;; value of log-view-message-re only since Emacs-23.
       (append `((,log-view-message-re . 'log-view-message-face))
               ;; log-view-font-lock-keywords
               '(("^ *committer: \
\\([^<(]+?\\)[  ]*[(<]\\([[:alnum:]_.+-]+@[[:alnum:]_.-]+\\)[>)]"
                  (1 'change-log-name)
                  (2 'change-log-email))
                 ("^ *timestamp: \\(.*\\)" (1 'change-log-date-face))))))

(defun vc-bzr-print-log (files &optional buffer) ; get buffer arg in Emacs 22
  "Get bzr change log for FILES into specified BUFFER."
  ;; Fixme: This might need the locale fixing up if things like `revno'
  ;; got localized, but certainly it shouldn't use LC_ALL=C.
  ;; NB.  Can't be async -- see `vc-bzr-post-command-function'.
  (vc-bzr-command "log" buffer 0 files)
  ;; FIXME: Until Emacs-23, VC was missing a hook to sort out the mode for
  ;; the buffer, or at least set the regexps right.
  (unless (fboundp 'vc-default-log-view-mode)
    (add-hook 'log-view-mode-hook 'vc-bzr-log-view-mode)))

(defun vc-bzr-show-log-entry (version)
  "Find entry for patch name VERSION in bzr change log buffer."
  (goto-char (point-min))
  (let (case-fold-search)
    (if (re-search-forward (concat "^-+\nrevno: " version "$") nil t)
        (beginning-of-line 0)
      (goto-char (point-min)))))

(autoload 'vc-diff-switches-list "vc" nil nil t)

(defun vc-bzr-diff (files &optional rev1 rev2 buffer)
  "VC bzr backend for diff."
  (let ((working (vc-workfile-version (if (consp files) (car files) files))))
    (if (and (equal rev1 working) (not rev2))
        (setq rev1 nil))
    (if (and (not rev1) rev2)
        (setq rev1 working))
    ;; NB.  Can't be async -- see `vc-bzr-post-command-function'.
    ;; bzr diff produces condition code 1 for some reason.
    (apply #'vc-bzr-command "diff" (or buffer "*vc-diff*") 1 files
           "--diff-options" (mapconcat 'identity (vc-diff-switches-list bzr)
                                       " ")
           (when rev1
             (if rev2
                 (list "-r" (format "%s..%s" rev1 rev2))
               (list "-r" rev1))))))

(defalias 'vc-bzr-diff-tree 'vc-bzr-diff)

;; Fixme: implement vc-bzr-dir-state, vc-bzr-dired-state-info

;; Fixme: vc-{next,previous}-version need fixing in vc.el to deal with
;; straight integer versions.

(defun vc-bzr-delete-file (file)
  "Delete FILE and delete it in the bzr repository."
  (condition-case ()
      (delete-file file)
    (file-error nil))
  (vc-bzr-command "remove" nil 0 file))

(defun vc-bzr-rename-file (old new)
  "Rename file from OLD to NEW using `bzr mv'."
  (vc-bzr-command "mv" nil 0 new old))

(defvar vc-bzr-annotation-table nil
  "Internal use.")
(make-variable-buffer-local 'vc-bzr-annotation-table)

(defun vc-bzr-annotate-command (file buffer &optional version)
  "Prepare BUFFER for `vc-annotate' on FILE.
Each line is tagged with the revision number, which has a `help-echo'
property containing author and date information."
  (apply #'vc-bzr-command "annotate" buffer 0 file "-l" "--all"
         (if version (list "-r" version)))
  (with-current-buffer buffer
    ;; Store the tags for the annotated source lines in a hash table
    ;; to allow saving space by sharing the text properties.
    (setq vc-bzr-annotation-table (make-hash-table :test 'equal))
    (goto-char (point-min))
    (while (re-search-forward "^\\( *[0-9]+\\) \\(.+\\) +\\([0-9]\\{8\\}\\) |"
                              nil t)
      (let* ((rev (match-string 1))
             (author (match-string 2))
             (date (match-string 3))
             (key (match-string 0))
             (tag (gethash key vc-bzr-annotation-table)))
        (unless tag
          (save-match-data
            (string-match " +\\'" author)
            (setq author (substring author 0 (match-beginning 0))))
          (setq tag (propertize rev 'help-echo (concat "Author: " author
                                                       ", date: " date)
                                'mouse-face 'highlight))
          (puthash key tag vc-bzr-annotation-table))
        (replace-match "")
        (insert tag " |")))))

;; Definition from Emacs 22
(unless (fboundp 'vc-annotate-convert-time)
(defun vc-annotate-convert-time (time)
  "Convert a time value to a floating-point number of days.
The argument TIME is a list as returned by `current-time' or
`encode-time', only the first two elements of that list are considered."
  (/ (+ (* (float (car time)) (lsh 1 16)) (cadr time)) 24 3600)))

(defun vc-bzr-annotate-time ()
  (when (re-search-forward "^ *[0-9]+ |" nil t)
    (let ((prop (get-text-property (line-beginning-position) 'help-echo)))
      (string-match "[0-9]+\\'" prop)
      (vc-annotate-convert-time
       (encode-time 0 0 0
                    (string-to-number (substring (match-string 0 prop) 6 8))
                    (string-to-number (substring (match-string 0 prop) 4 6))
                    (string-to-number (substring (match-string 0 prop) 0 4))
                    )))))

(defun vc-bzr-annotate-extract-revision-at-line ()
  "Return revision for current line of annoation buffer, or nil.
Return nil if current line isn't annotated."
  (save-excursion
    (beginning-of-line)
    (if (looking-at " *\\([0-9]+\\) | ")
        (match-string-no-properties 1))))

;; Not needed for Emacs 22
(defun vc-bzr-annotate-difference (point)
  (let ((next-time (vc-bzr-annotate-time)))
    (if next-time
        (- (vc-annotate-convert-time (current-time)) next-time))))

(defun vc-bzr-command-discarding-stderr (command &rest args)
  "Execute shell command COMMAND (with ARGS); return its output and exitcode.
Return value is a cons (EXITCODE . OUTPUT), where EXITCODE is
the (numerical) exit code of the process, and OUTPUT is a string
containing whatever the process sent to its standard output
stream.  Standard error output is discarded."
  (with-temp-buffer
    (cons
     (apply 'call-process command nil (list (current-buffer) nil) nil args)
     (buffer-substring (point-min) (point-max)))))

;; TODO: it would be nice to mark the conflicted files in  VC Dired,
;; and implement a command to run ediff and `bzr resolve' once the 
;; changes have been merged.
(defun vc-bzr-dir-state (dir &optional localp)
  "Find the VC state of all files in DIR.
Optional argument LOCALP is always ignored."
  (let ((bzr-root-directory (vc-bzr-root dir))
        (at-start t)
        current-bzr-state current-vc-state)
    ;; Check that DIR is a bzr repository.
    (unless (file-name-absolute-p bzr-root-directory)
      (error "Cannot find bzr repository for directory `%s'" dir))
    ;; `bzr ls --versioned' lists all versioned files;
    ;; assume they are up-to-date, unless we are given
    ;; evidence of the contrary.
    (setq at-start t)
    (with-temp-buffer
      (vc-bzr-command "ls" t 0 nil "--versioned" "--non-recursive")
      (goto-char (point-min))
      (while (or at-start
                 (eq 0 (forward-line)))
        (setq at-start nil)
        (let ((file (expand-file-name
                     (buffer-substring-no-properties 
                      (line-beginning-position) (line-end-position))
                     bzr-root-directory)))
          (vc-file-setprop file 'vc-state 'up-to-date)
          ;; XXX: is this correct? what happens if one 
          ;; mixes different SCMs in the same dir?
          (vc-file-setprop file 'vc-backend 'Bzr))))
    ;; `bzr status' reports on added/modified/renamed and unknown/ignored files
    (setq at-start t)
    (with-temp-buffer 
      (vc-bzr-command "status" t 0 nil)
      (goto-char (point-min))
      (while (or at-start
                 (eq 0 (forward-line)))
        (setq at-start nil)
        (cond 
         ((looking-at "^added") 
          (setq current-vc-state 'edited)
          (setq current-bzr-state 'added))
         ((looking-at "^modified") 
          (setq current-vc-state 'edited)
          (setq current-bzr-state 'modified))
         ((looking-at "^renamed") 
          (setq current-vc-state 'edited)
          (setq current-bzr-state 'renamed))
         ((looking-at "^\\(unknown\\|ignored\\)")
          (setq current-vc-state nil)
          (setq current-bzr-state 'not-versioned))
         ((looking-at "  ")
          ;; file names are indented by two spaces
          (when current-vc-state
            (let ((file (expand-file-name
                         (buffer-substring-no-properties
                          (match-end 0) (line-end-position))
                         bzr-root-directory)))
              (vc-file-setprop file 'vc-state current-vc-state)
              (vc-file-setprop file 'vc-bzr-state current-bzr-state)
              (when (eq 'added current-bzr-state)
                (vc-file-setprop file 'vc-workfile-version "0"))))
          (when (eq 'not-versioned current-bzr-state)
            (let ((file (expand-file-name
                         (buffer-substring-no-properties
                          (match-end 0) (line-end-position))
                         bzr-root-directory)))
              (vc-file-setprop file 'vc-backend 'none)
              (vc-file-setprop file 'vc-state nil))))
         (t
          ;; skip this part of `bzr status' output
          (setq current-vc-state nil)
          (setq current-bzr-state nil)))))))

(defun vc-bzr-dired-state-info (file)
  "Bzr-specific version of `vc-dired-state-info'."
  (if (eq 'edited (vc-state file))
      (let ((bzr-state (vc-file-getprop file 'vc-bzr-state)))
        (if bzr-state
            (concat "(" (symbol-name bzr-state) ")")
          ;; else fall back to default vc representation
          (vc-default-dired-state-info 'Bzr file)))))

;; In case of just `(load "vc-bzr")', but that's probably the wrong
;; way to do it.
(add-to-list 'vc-handled-backends 'Bzr)

(eval-after-load "vc"
  '(add-to-list 'vc-directory-exclusion-list vc-bzr-admin-dirname t))

(defconst vc-bzr-unload-hook
  (lambda ()
    (setq vc-handled-backends (delq 'Bzr vc-handled-backends))
    (remove-hook 'vc-post-command-functions 'vc-bzr-post-command-function)))

(provide 'vc-bzr)
;; arch-tag: 8101bad8-4e92-4e7d-85ae-d8e08b4e7c06
;;; vc-bzr.el ends here