lisp/vc/log-view.el

   1 ;;; log-view.el --- Major mode for browsing revision log histories -*- lexical-binding: t -*-
   2
   3 ;; Copyright (C) 1999-2018 Free Software Foundation, Inc.
   4
   5 ;; Author: Stefan Monnier <monnier@iro.umontreal.ca>
   6 ;; Keywords: tools, vc
   7
   8 ;; This file is part of GNU Emacs.
   9
  10 ;; GNU Emacs is free software: you can redistribute it and/or modify
  11 ;; it under the terms of the GNU General Public License as published by
  12 ;; the Free Software Foundation, either version 3 of the License, or
  13 ;; (at your option) any later version.
  14
  15 ;; GNU Emacs is distributed in the hope that it will be useful,
  16 ;; but WITHOUT ANY WARRANTY; without even the implied warranty of
  17 ;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  18 ;; GNU General Public License for more details.
  19
  20 ;; You should have received a copy of the GNU General Public License
  21 ;; along with GNU Emacs.  If not, see <https://www.gnu.org/licenses/>.
  22
  23 ;;; Commentary:
  24
  25 ;; Major mode to browse revision log histories.
  26 ;; Currently supports the format output by:
  27 ;; SCCS, RCS, CVS, Subversion, DaRCS, and Mercurial.
  28
  29 ;; Examples of log output:
  30
  31 ;;;; SCCS:
  32
  33 ;;;; RCS/CVS:
  34
  35 ;; ----------------------------
  36 ;; revision 1.35        locked by: turlutut
  37 ;; date: 2005-03-22 18:48:38 +0000;  author: monnier;  state: Exp;  lines: +6 -8
  38 ;; (gnus-display-time-event-handler):
  39 ;; Check display-time-timer at runtime rather than only at load time
  40 ;; in case display-time-mode is turned off in the mean time.
  41 ;; ----------------------------
  42 ;; revision 1.34
  43 ;; date: 2005-02-09 15:50:38 +0000;  author: kfstorm;  state: Exp;  lines: +7 -7
  44 ;; branches:  1.34.2;
  45 ;; Change release version from 21.4 to 22.1 throughout.
  46 ;; Change development version from 21.3.50 to 22.0.50.
  47
  48 ;;;; Subversion:
  49
  50 ;; ------------------------------------------------------------------------
  51 ;; r4622 | ckuethe | 2007-12-23 18:18:01 -0500 (Sun, 23 Dec 2007) | 2 lines
  52 ;;
  53 ;; uBlox AEK-4T in binary mode. Added to unstable because it breaks gpsfake
  54 ;;
  55 ;; ------------------------------------------------------------------------
  56 ;; r4621 | ckuethe | 2007-12-23 16:48:11 -0500 (Sun, 23 Dec 2007) | 3 lines
  57 ;;
  58 ;; Add a note about requiring usbfs to use the garmin gps18 (usb)
  59 ;; Mention firmware testing the AC12 with firmware BQ00 and BQ04
  60 ;;
  61 ;; ------------------------------------------------------------------------
  62 ;; r4620 | ckuethe | 2007-12-23 15:52:34 -0500 (Sun, 23 Dec 2007) | 1 line
  63 ;;
  64 ;; add link to latest hardware reference
  65 ;; ------------------------------------------------------------------------
  66 ;; r4619 | ckuethe | 2007-12-23 14:37:31 -0500 (Sun, 23 Dec 2007) | 1 line
  67 ;;
  68 ;; there is now a regression test for AC12 without raw data output
  69
  70 ;;;; Darcs:
  71
  72 ;; Changes to darcsum.el:
  73 ;;
  74 ;; Mon Nov 28 15:19:38 GMT 2005  Dave Love <fx@gnu.org>
  75 ;;   * Abstract process startup into darcsum-start-process.  Use TERM=dumb.
  76 ;;   TERM=dumb avoids escape characters, at least, for any old darcs that
  77 ;;   doesn't understand DARCS_DONT_COLOR & al.
  78 ;;
  79 ;; Thu Nov 24 15:20:45 GMT 2005  Dave Love <fx@gnu.org>
  80 ;;   * darcsum-mode-related changes.
  81 ;;   Don't call font-lock-mode (unnecessary) or use-local-map (redundant).
  82 ;;   Use mode-class 'special.  Add :group.
  83 ;;   Add trailing-whitespace option to mode hook and fix
  84 ;;   darcsum-display-changeset not to use trailing whitespace.
  85
  86 ;;;; Mercurial
  87
  88 ;; changeset:   11:8ff1a4166444
  89 ;; tag:         tip
  90 ;; user:        Eric S. Raymond <esr@thyrsus.com>
  91 ;; date:        Wed Dec 26 12:18:58 2007 -0500
  92 ;; summary:     Explain keywords.  Add markup fixes.
  93 ;;
  94 ;; changeset:   10:20abc7ab09c3
  95 ;; user:        Eric S. Raymond <esr@thyrsus.com>
  96 ;; date:        Wed Dec 26 11:37:28 2007 -0500
  97 ;; summary:     Typo fixes.
  98 ;;
  99 ;; changeset:   9:ada9f4da88aa
 100 ;; user:        Eric S. Raymond <esr@thyrsus.com>
 101 ;; date:        Wed Dec 26 11:23:00 2007 -0500
 102 ;; summary:     Add RCS example session.
 103
 104 ;;; Todo:
 105
 106 ;; - add ability to modify a log-entry (via cvs-mode-admin ;-)
 107 ;; - remove references to cvs-*
 108 ;; - make it easier to add support for new backends without changing the code.
 109
 110 ;;; Code:
 111
 112 (require 'pcvs-util)
 113 (autoload 'vc-find-revision "vc")
 114 (autoload 'vc-diff-internal "vc")
 115
 116 (defvar cvs-minor-wrap-function)
 117 (defvar cvs-force-command)
 118
 119 (defgroup log-view nil
 120   "Major mode for browsing log output of revision log histories."
 121   :group 'pcl-cvs
 122   :prefix "log-view-")
 123
 124 (easy-mmode-defmap log-view-mode-map
 125   '(
 126     ("-"        .       negative-argument)
 127     ("0"        .       digit-argument)
 128     ("1"        .       digit-argument)
 129     ("2"        .       digit-argument)
 130     ("3"        .       digit-argument)
 131     ("4"        .       digit-argument)
 132     ("5"        .       digit-argument)
 133     ("6"        .       digit-argument)
 134     ("7"        .       digit-argument)
 135     ("8"        .       digit-argument)
 136     ("9"        .       digit-argument)
 137
 138     ("\C-m" . log-view-toggle-entry-display)
 139     ("m" . log-view-toggle-mark-entry)
 140     ("e" . log-view-modify-change-comment)
 141     ("d" . log-view-diff)
 142     ("=" . log-view-diff)
 143     ("D" . log-view-diff-changeset)
 144     ("a" . log-view-annotate-version)
 145     ("f" . log-view-find-revision)
 146     ("n" . log-view-msg-next)
 147     ("p" . log-view-msg-prev)
 148     ("\t" . log-view-msg-next)
 149     ([backtab] . log-view-msg-prev)
 150     ("N" . log-view-file-next)
 151     ("P" . log-view-file-prev)
 152     ("\M-n" . log-view-file-next)
 153     ("\M-p" . log-view-file-prev))
 154   "Log-View's keymap."
 155   :inherit special-mode-map
 156   :group 'log-view)
 157
 158 (easy-menu-define log-view-mode-menu log-view-mode-map
 159   "Log-View Display Menu"
 160   `("Log-View"
 161     ;; XXX Do we need menu entries for these?
 162     ;; ["Quit"  quit-window]
 163     ;; ["Kill This Buffer"  kill-this-buffer]
 164     ["Mark Log Entry for Diff"  set-mark-command
 165      :help ""]
 166     ["Diff Revisions"  log-view-diff
 167      :help "Get the diff between two revisions"]
 168     ["Changeset Diff"  log-view-diff-changeset
 169      :help "Get the changeset diff between two revisions"]
 170     ["Visit Version"  log-view-find-revision
 171      :help "Visit the version at point"]
 172     ["Annotate Version"  log-view-annotate-version
 173      :help "Annotate the version at point"]
 174     ["Modify Log Comment" log-view-modify-change-comment
 175      :help "Edit the change comment displayed at point"]
 176     ["Toggle Details at Point" log-view-toggle-entry-display
 177      :active log-view-expanded-log-entry-function]
 178     "-----"
 179     ["Next Log Entry"  log-view-msg-next
 180      :help "Go to the next count'th log message"]
 181     ["Previous Log Entry"  log-view-msg-prev
 182      :help "Go to the previous count'th log message"]
 183     ["Next File"  log-view-file-next
 184      :help "Go to the next count'th file"]
 185     ["Previous File"  log-view-file-prev
 186      :help "Go to the previous count'th file"]))
 187
 188 (defvar log-view-mode-hook nil
 189   "Hook run at the end of `log-view-mode'.")
 190
 191 (defvar log-view-expanded-log-entry-function nil
 192   "Function returning the detailed description of a Log View entry.
 193 It is called by the command `log-view-toggle-entry-display' with
 194 one arg, the revision tag (a string), and should return a string.
 195 If it is nil, `log-view-toggle-entry-display' does nothing.")
 196
 197 (defface log-view-file
 198   '((((class color) (background light))
 199      (:background "grey70" :weight bold))
 200     (t (:weight bold)))
 201   "Face for the file header line in `log-view-mode'."
 202   :group 'log-view)
 203
 204 (defface log-view-message
 205   '((((class color) (background light))
 206      (:background "grey85"))
 207     (t (:weight bold)))
 208   "Face for the message header line in `log-view-mode'."
 209   :group 'log-view)
 210
 211 (defvar log-view-file-re
 212   (concat "^\\(?:Working file: \\(?1:.+\\)"                ;RCS and CVS.
 213           ;; Subversion has no such thing??
 214           "\\|\\(?:SCCS/s\\.\\|Changes to \\)\\(?1:.+\\):" ;SCCS and Darcs.
 215           "\\)\n")                    ;Include the \n for font-lock reasons.
 216   "Regexp matching the text identifying the file.
 217 The match group number 1 should match the file name itself.")
 218
 219 (defvar log-view-per-file-logs t
 220   "Set if to t if the logs are shown one file at a time.")
 221
 222 (defvar log-view-message-re
 223   (concat "^\\(?:revision \\(?1:[.0-9]+\\)\\(?:\t.*\\)?" ; RCS and CVS.
 224           "\\|r\\(?1:[0-9]+\\) | .* | .*"                ; Subversion.
 225           "\\|D \\(?1:[.0-9]+\\) .*"                     ; SCCS.
 226           ;; Darcs doesn't have revision names.  VC-darcs uses patch names
 227           ;; instead.  Darcs patch names are hashcodes, which do not appear
 228           ;; in the log output :-(, but darcs accepts any prefix of the log
 229           ;; message as a patch name, so we match the first line of the log
 230           ;; message.
 231           ;; First loosely match the date format.
 232           (concat "\\|[^ \n].*[^0-9\n][0-9][0-9]:[0-9][0-9][^0-9\n].*[^ \n]"
 233                   ;;Email of user and finally Msg, used as revision name.
 234                   "  .*@.*\n\\(?:  \\* \\(?1:.*\\)\\)?")
 235           "\\)$")
 236   "Regexp matching the text identifying a revision.
 237 The match group number 1 should match the revision number itself.")
 238
 239 (defvar log-view-font-lock-keywords
 240   ;; We use `eval' so as to use the buffer-local value of log-view-file-re
 241   ;; and log-view-message-re, if applicable.
 242   '((eval . `(,log-view-file-re
 243               (1 (if (boundp 'cvs-filename-face) cvs-filename-face))
 244               (0 'log-view-file append)))
 245     (eval . `(,log-view-message-re . 'log-view-message))))
 246
 247 (defconst log-view-font-lock-defaults
 248   '(log-view-font-lock-keywords t nil nil nil))
 249
 250 (defvar log-view-vc-fileset nil
 251   "The VC fileset corresponding to the current log.")
 252
 253 (defvar log-view-vc-backend nil
 254   "The VC backend that created the current log.")
 255
 256 ;;;;
 257 ;;;; Actual code
 258 ;;;;
 259
 260 ;;;###autoload
 261 (define-derived-mode log-view-mode special-mode "Log-View"
 262   "Major mode for browsing CVS log output."
 263   (setq buffer-read-only t)
 264   (set (make-local-variable 'font-lock-defaults) log-view-font-lock-defaults)
 265   (set (make-local-variable 'beginning-of-defun-function)
 266        'log-view-beginning-of-defun)
 267   (set (make-local-variable 'end-of-defun-function)
 268        'log-view-end-of-defun)
 269   (set (make-local-variable 'cvs-minor-wrap-function) 'log-view-minor-wrap)
 270   (hack-dir-local-variables-non-file-buffer))
 271
 272 ;;;;
 273 ;;;; Navigation
 274 ;;;;
 275
 276 ;; define log-view-{msg,file}-{next,prev}
 277 (easy-mmode-define-navigation log-view-msg log-view-message-re "log message")
 278 (easy-mmode-define-navigation log-view-file log-view-file-re "file")
 279
 280 (defun log-view-goto-rev (rev)
 281   "Go to revision REV."
 282   (goto-char (point-min))
 283   (ignore-errors
 284     (while (not (equal rev (log-view-current-tag)))
 285       (log-view-msg-next))
 286     t))
 287
 288 ;;;;
 289 ;;;; Linkage to PCL-CVS (mostly copied from cvs-status.el)
 290 ;;;;
 291
 292 (defconst log-view-dir-re "^cvs[.ex]* [a-z]+: Logging \\(.+\\)$")
 293
 294 (defun log-view-current-file ()
 295   "Return the current file."
 296   (save-excursion
 297     (forward-line 1)
 298     (or (re-search-backward log-view-file-re nil t)
 299         (re-search-forward log-view-file-re nil t)
 300         (error "Unable to determine the current file"))
 301     (let* ((file (match-string 1))
 302            (cvsdir (and (re-search-backward log-view-dir-re nil t)
 303                         (match-string 1)))
 304            (pcldir (and (boundp 'cvs-pcl-cvs-dirchange-re)
 305                         (re-search-backward cvs-pcl-cvs-dirchange-re nil t)
 306                         (match-string 1)))
 307            (dir ""))
 308       (let ((default-directory ""))
 309         (when pcldir (setq dir (expand-file-name pcldir dir)))
 310         (when cvsdir (setq dir (expand-file-name cvsdir dir))))
 311       (expand-file-name file dir))))
 312
 313 (defun log-view-current-entry (&optional pos move)
 314   "Return the position and revision tag of the Log View entry at POS.
 315 This is a list (BEG TAG), where BEG is a buffer position and TAG
 316 is a string.  If POS is nil or omitted, it defaults to point.
 317 If there is no entry at POS, return nil.
 318
 319 If optional arg MOVE is non-nil, move point to BEG if found.
 320 Otherwise, don't move point."
 321   (let ((looping t)
 322         result)
 323     (save-excursion
 324       (when pos (goto-char pos))
 325       (forward-line 0)
 326       ;; Treat "---" separator lines as part of the following revision.
 327       (forward-line (if (looking-at "-\\{20,\\}$") 2 1))
 328       (while looping
 329         (setq pos (re-search-backward log-view-message-re nil 'move)
 330               looping (and pos (log-view-inside-comment-p (point)))))
 331       (when pos
 332         (setq result
 333               (list pos (match-string-no-properties 1)))))
 334     (and move result (goto-char pos))
 335     result))
 336
 337 (defun log-view-inside-comment-p (pos)
 338   "Return non-nil if POS lies inside an expanded log entry."
 339   (eq (get-text-property pos 'log-view-comment) t))
 340
 341 (defun log-view-current-tag (&optional pos)
 342   "Return the revision tag (a string) of the Log View entry at POS.
 343 if POS is omitted or nil, it defaults to point."
 344   (cadr (log-view-current-entry pos)))
 345
 346 (defun log-view-toggle-mark-entry ()
 347   "Toggle the marked state for the log entry at point.
 348 Individual log entries can be marked and unmarked.  The marked
 349 entries are denoted by changing their background color.
 350 `log-view-get-marked' returns the list of tags for the marked
 351 log entries."
 352   (interactive)
 353   (save-excursion
 354     (let* ((entry (log-view-current-entry nil t))
 355            (beg (car entry))
 356            found)
 357       (when entry
 358         ;; Look to see if the current entry is marked.
 359         (setq found (get-char-property beg 'log-view-self))
 360         (if found
 361             (delete-overlay found)
 362           ;; Create an overlay covering this entry and change its color.
 363           (let* ((end (if (get-text-property beg 'log-view-entry-expanded)
 364                           (next-single-property-change beg 'log-view-comment)
 365                         (log-view-end-of-defun)
 366                         (point)))
 367                  (ov (make-overlay beg end)))
 368             (overlay-put ov 'face 'log-view-file)
 369             ;; This is used to check if the overlay is present.
 370             (overlay-put ov 'log-view-self ov)
 371             (overlay-put ov 'log-view-marked (nth 1 entry))))))))
 372
 373 (defun log-view-get-marked ()
 374   "Return the list of tags for the marked log entries."
 375   (save-excursion
 376     (let ((pos (point-min))
 377           marked-list ov)
 378       (while (setq pos (next-single-property-change pos 'face))
 379         (when (setq ov (get-char-property pos 'log-view-self))
 380           (push (overlay-get ov 'log-view-marked) marked-list)
 381           (setq pos (overlay-end ov))))
 382       marked-list)))
 383
 384 (defun log-view-toggle-entry-display ()
 385   "If possible, expand the current Log View entry.
 386 This calls `log-view-expanded-log-entry-function' to do the work."
 387   (interactive)
 388   ;; Don't do anything unless `log-view-expanded-log-entry-function'
 389   ;; is defined in this mode.
 390   (when (functionp log-view-expanded-log-entry-function)
 391     (let* ((opoint (point))
 392            (entry (log-view-current-entry nil t))
 393            (beg (car entry))
 394            (buffer-read-only nil))
 395       (when entry
 396         (if (get-text-property beg 'log-view-entry-expanded)
 397             ;; If the entry is expanded, collapse it.
 398             (let ((pos (next-single-property-change beg 'log-view-comment)))
 399               (unless (and pos (log-view-inside-comment-p pos))
 400                 (error "Broken markup in `log-view-toggle-entry-display'"))
 401               (delete-region pos
 402                              (or
 403                               (next-single-property-change pos 'log-view-comment)
 404                               (point-max)))
 405               (put-text-property beg (1+ beg) 'log-view-entry-expanded nil)
 406               (if (< opoint pos)
 407                   (goto-char opoint)))
 408           ;; Otherwise, expand the entry.
 409           (let ((long-entry (funcall log-view-expanded-log-entry-function
 410                                      (nth 1 entry))))
 411             (when long-entry
 412               (put-text-property beg (1+ beg) 'log-view-entry-expanded t)
 413               (log-view-end-of-defun)
 414               (setq beg (point))
 415               (insert long-entry "\n")
 416               (add-text-properties
 417                beg (point)
 418                '(font-lock-face font-lock-comment-face log-view-comment t))
 419               (goto-char opoint))))))))
 420
 421 (defun log-view-beginning-of-defun (&optional arg)
 422   "Move backward to the beginning of a Log View entry.
 423 With ARG, do it that many times.  Negative ARG means move forward
 424 to the beginning of the ARGth following entry.
 425
 426 This is Log View mode's default `beginning-of-defun-function'.
 427 It assumes that a log entry starts with a line matching
 428 `log-view-message-re'."
 429   (when (null arg) (setf arg 1))
 430   (if (< arg 0)
 431       ;; In log view, the end of one defun is the beginning of the
 432       ;; next, so punting to log-view-end-of-defun is safe in this
 433       ;; context.
 434       (log-view-end-of-defun (- arg))
 435     (let ((found t))
 436       (while (> arg 0)
 437         (setf arg (1- arg))
 438         (let ((cur-start (log-view-current-entry)))
 439           (setf found
 440                 (cond ((null cur-start)
 441                        (goto-char (point-min))
 442                        nil)
 443                       ((>= (car cur-start) (point))
 444                        (unless (bobp)
 445                          (forward-line -1)
 446                          (setf arg (1+ arg)))
 447                        nil)
 448                       (t
 449                        (goto-char (car cur-start))
 450                        t)))))
 451       found)))
 452
 453 (defun log-view-end-of-defun-1 ()
 454   "Move forward to the next Log View entry."
 455   (let ((looping t))
 456     (if (looking-at log-view-message-re)
 457         (goto-char (match-end 0)))
 458     (while looping
 459       (cond
 460        ((re-search-forward log-view-message-re nil 'move)
 461         (unless (log-view-inside-comment-p (point))
 462           (setq looping nil)
 463           (goto-char (match-beginning 0))))
 464        ;; Don't advance past the end buttons inserted by
 465        ;; `vc-print-log-setup-buttons'.
 466        ((looking-back "Show 2X entries    Show unlimited entries"
 467                       (line-beginning-position))
 468         (setq looping nil)
 469         (forward-line -1))
 470        ;; There are no buttons if we've turned on unlimited entries.
 471        ((eobp)
 472         (setq looping nil))))))
 473
 474 (defun log-view-end-of-defun (&optional arg)
 475   "Move forward to the next Log View entry.
 476 Works like `end-of-defun'."
 477   (when (null arg) (setf arg 1))
 478   (if (< arg 0)
 479       (log-view-beginning-of-defun (- arg))
 480     (dotimes (_n arg)
 481       (log-view-end-of-defun-1)
 482       t)))
 483
 484 (defvar cvs-minor-current-files)
 485 (defvar cvs-branch-prefix)
 486 (defvar cvs-secondary-branch-prefix)
 487
 488 (defun log-view-minor-wrap (buf f)
 489   (let ((data (with-current-buffer buf
 490                 (let* ((beg (point))
 491                        (end (if (use-region-p) (mark) (point)))
 492                        (fr (log-view-current-tag beg))
 493                        (to (log-view-current-tag end)))
 494                   (when (string-equal fr to)
 495                     (save-excursion
 496                       (goto-char end)
 497                       (log-view-msg-next)
 498                       (setq to (log-view-current-tag))))
 499                   (cons
 500                    ;; The first revision has to be the one at point, for
 501                    ;; operations that only take one revision
 502                    ;; (e.g. cvs-mode-edit).
 503                    (cons (log-view-current-file) fr)
 504                    (cons (log-view-current-file) to))))))
 505     (let ((cvs-branch-prefix (cdar data))
 506           (cvs-secondary-branch-prefix (and (cdar data) (cddr data)))
 507           (cvs-minor-current-files
 508            (cons (caar data)
 509                  (when (and (cadr data) (not (equal (caar data) (cadr data))))
 510                    (list (cadr data)))))
 511           ;; FIXME:  I need to force because the fileinfos are UNKNOWN
 512           (cvs-force-command "/F"))
 513       (funcall f))))
 514
 515 (defun log-view-find-revision (pos)
 516   "Visit the version at POS.
 517 If called interactively, visit the version at point."
 518   (interactive "d")
 519   (unless log-view-per-file-logs
 520     (when (> (length log-view-vc-fileset) 1)
 521       (error "Multiple files shown in this buffer, cannot use this command here")))
 522   (save-excursion
 523     (goto-char pos)
 524     (switch-to-buffer (vc-find-revision (if log-view-per-file-logs
 525                                             (log-view-current-file)
 526                                           (car log-view-vc-fileset))
 527                                         (log-view-current-tag)))))
 528
 529
 530 (defun log-view-extract-comment ()
 531   "Parse comment from around the current point in the log."
 532   (save-excursion
 533     (let (st en (backend (vc-backend (log-view-current-file))))
 534       (log-view-end-of-defun)
 535       (cond ((eq backend 'SVN)
 536              (forward-line -1)))
 537       (setq en (point))
 538       (or (log-view-current-entry nil t)
 539           (throw 'beginning-of-buffer nil))
 540       (cond ((memq backend '(SCCS RCS CVS SVN))
 541              (forward-line 2))
 542             ((eq backend 'Hg)
 543              (forward-line 4)
 544              (re-search-forward "summary: *" nil t)))
 545       (setq st (point))
 546       (buffer-substring st en))))
 547
 548 (declare-function vc-modify-change-comment "vc" (files rev oldcomment))
 549
 550 (defun log-view-modify-change-comment ()
 551   "Edit the change comment displayed at point."
 552   (interactive)
 553   (vc-modify-change-comment (list (if log-view-per-file-logs
 554                                       (log-view-current-file)
 555                                     (car log-view-vc-fileset)))
 556                             (log-view-current-tag)
 557                             (log-view-extract-comment)))
 558
 559 (defun log-view-annotate-version (pos)
 560   "Annotate the version at POS.
 561 If called interactively, annotate the version at point."
 562   (interactive "d")
 563   (unless log-view-per-file-logs
 564     (when (> (length log-view-vc-fileset) 1)
 565       (error "Multiple files shown in this buffer, cannot use this command here")))
 566   (save-excursion
 567     (goto-char pos)
 568     (vc-annotate (if log-view-per-file-logs
 569                      (log-view-current-file)
 570                    (car log-view-vc-fileset))
 571                  (log-view-current-tag))))
 572
 573 ;;
 574 ;; diff
 575 ;;
 576
 577 (defun log-view-diff (beg end)
 578   "Get the diff between two revisions.
 579 If the region is inactive or the mark is on the revision at
 580 point, get the diff between the revision at point and its
 581 previous revision.  Otherwise, get the diff between the revisions
 582 where the region starts and ends.
 583
 584 Unlike `log-view-diff-changeset', this function only shows the
 585 part of the changeset which affected the currently considered
 586 file(s)."
 587   (interactive
 588    (list (if (use-region-p) (region-beginning) (point))
 589          (if (use-region-p) (region-end) (point))))
 590   (log-view-diff-common beg end))
 591
 592 (defun log-view-diff-changeset (beg end)
 593   "Get the diff between two revisions.
 594 If the region is inactive or the mark is on the revision at
 595 point, get the diff between the revision at point and its
 596 previous revision.  Otherwise, get the diff between the revisions
 597 where the region starts and ends.
 598
 599 Unlike `log-view-diff' this function shows the whole changeset,
 600 including changes affecting other files than the currently
 601 considered file(s)."
 602   (interactive
 603    (list (if (use-region-p) (region-beginning) (point))
 604          (if (use-region-p) (region-end) (point))))
 605   (when (eq (vc-call-backend log-view-vc-backend 'revision-granularity) 'file)
 606     (error "The %s backend does not support changeset diffs" log-view-vc-backend))
 607   (let ((default-directory (vc-root-dir)))
 608     (log-view-diff-common beg end t)))
 609
 610 (defun log-view-diff-common (beg end &optional whole-changeset)
 611   (let* ((to (log-view-current-tag beg))
 612          (fr-entry (log-view-current-entry end))
 613          (fr (cadr fr-entry)))
 614     ;; When TO and FR are the same, or when point is on a line after
 615     ;; the last entry, look at the previous revision.
 616     (when (or (string-equal fr to)
 617               (>= (point)
 618                   (save-excursion
 619                     (goto-char (car fr-entry))
 620                     (forward-line))))
 621       (setq fr (vc-call-backend log-view-vc-backend 'previous-revision nil fr)))
 622     (vc-diff-internal
 623      t (list log-view-vc-backend
 624              ;; The value passed here should follow what
 625              ;; `vc-deduce-fileset' returns.  If we want to see the
 626              ;; diff for all the files in the changeset, pass NIL for
 627              ;; the file list.
 628              (unless whole-changeset
 629                (if log-view-per-file-logs
 630                    (list (log-view-current-file))
 631                  log-view-vc-fileset)))
 632      fr to)))
 633
 634 (provide 'log-view)
 635
 636 ;;; log-view.el ends here