lisp/smerge-mode.el

   1 ;;; smerge-mode.el --- Minor mode to resolve diff3 conflicts
   2
   3 ;; Copyright (C) 1999, 2000, 2001, 2002, 2003,
   4 ;;   2004, 2005, 2006, 2007, 2008 Free Software Foundation, Inc.
   5
   6 ;; Author: Stefan Monnier <monnier@iro.umontreal.ca>
   7 ;; Keywords: tools revision-control merge diff3 cvs conflict
   8
   9 ;; This file is part of GNU Emacs.
  10
  11 ;; GNU Emacs is free software; you can redistribute it and/or modify
  12 ;; it under the terms of the GNU General Public License as published by
  13 ;; the Free Software Foundation; either version 3, or (at your option)
  14 ;; any later version.
  15
  16 ;; GNU Emacs is distributed in the hope that it will be useful,
  17 ;; but WITHOUT ANY WARRANTY; without even the implied warranty of
  18 ;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  19 ;; GNU General Public License for more details.
  20
  21 ;; You should have received a copy of the GNU General Public License
  22 ;; along with GNU Emacs; see the file COPYING.  If not, write to the
  23 ;; Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
  24 ;; Boston, MA 02110-1301, USA.
  25
  26 ;;; Commentary:
  27
  28 ;; Provides a lightweight alternative to emerge/ediff.
  29 ;; To use it, simply add to your .emacs the following lines:
  30 ;;
  31 ;;   (autoload 'smerge-mode "smerge-mode" nil t)
  32 ;;
  33 ;; you can even have it turned on automatically with the following
  34 ;; piece of code in your .emacs:
  35 ;;
  36 ;;   (defun sm-try-smerge ()
  37 ;;     (save-excursion
  38 ;;       (goto-char (point-min))
  39 ;;       (when (re-search-forward "^<<<<<<< " nil t)
  40 ;;         (smerge-mode 1))))
  41 ;;   (add-hook 'find-file-hook 'sm-try-smerge t)
  42
  43 ;;; Todo:
  44
  45 ;; - if requested, ask the user whether he wants to call ediff right away
  46
  47 ;;; Code:
  48
  49 (eval-when-compile (require 'cl))
  50
  51
  52 ;;; The real definition comes later.
  53 (defvar smerge-mode)
  54
  55 (defgroup smerge ()
  56   "Minor mode to highlight and resolve diff3 conflicts."
  57   :group 'tools
  58   :prefix "smerge-")
  59
  60 (defcustom smerge-diff-buffer-name "*vc-diff*"
  61   "Buffer name to use for displaying diffs."
  62   :group 'smerge
  63   :type '(choice
  64           (const "*vc-diff*")
  65           (const "*cvs-diff*")
  66           (const "*smerge-diff*")
  67           string))
  68
  69 (defcustom smerge-diff-switches
  70   (append '("-d" "-b")
  71           (if (listp diff-switches) diff-switches (list diff-switches)))
  72   "A list of strings specifying switches to be passed to diff.
  73 Used in `smerge-diff-base-mine' and related functions."
  74   :group 'smerge
  75   :type '(repeat string))
  76
  77 (defcustom smerge-auto-leave t
  78   "Non-nil means to leave `smerge-mode' when the last conflict is resolved."
  79   :group 'smerge
  80   :type 'boolean)
  81
  82 (defcustom smerge-auto-refine t
  83   "Automatically highlight changes in detail as the user visits conflicts."
  84   :group 'smerge
  85   :type 'boolean)
  86
  87 (defface smerge-mine
  88   '((((min-colors 88) (background light))
  89      (:foreground "blue1"))
  90     (((background light))
  91      (:foreground "blue"))
  92     (((min-colors 88) (background dark))
  93      (:foreground "cyan1"))
  94     (((background dark))
  95      (:foreground "cyan")))
  96   "Face for your code."
  97   :group 'smerge)
  98 ;; backward-compatibility alias
  99 (put 'smerge-mine-face 'face-alias 'smerge-mine)
 100 (defvar smerge-mine-face 'smerge-mine)
 101
 102 (defface smerge-other
 103   '((((background light))
 104      (:foreground "darkgreen"))
 105     (((background dark))
 106      (:foreground "lightgreen")))
 107   "Face for the other code."
 108   :group 'smerge)
 109 ;; backward-compatibility alias
 110 (put 'smerge-other-face 'face-alias 'smerge-other)
 111 (defvar smerge-other-face 'smerge-other)
 112
 113 (defface smerge-base
 114   '((((min-colors 88) (background light))
 115      (:foreground "red1"))
 116     (((background light))
 117      (:foreground "red"))
 118     (((background dark))
 119      (:foreground "orange")))
 120   "Face for the base code."
 121   :group 'smerge)
 122 ;; backward-compatibility alias
 123 (put 'smerge-base-face 'face-alias 'smerge-base)
 124 (defvar smerge-base-face 'smerge-base)
 125
 126 (defface smerge-markers
 127   '((((background light))
 128      (:background "grey85"))
 129     (((background dark))
 130      (:background "grey30")))
 131   "Face for the conflict markers."
 132   :group 'smerge)
 133 ;; backward-compatibility alias
 134 (put 'smerge-markers-face 'face-alias 'smerge-markers)
 135 (defvar smerge-markers-face 'smerge-markers)
 136
 137 (defface smerge-refined-change
 138   '((t :background "yellow"))
 139   "Face used for char-based changes shown by `smerge-refine'."
 140   :group 'smerge)
 141
 142 (easy-mmode-defmap smerge-basic-map
 143   `(("n" . smerge-next)
 144     ("p" . smerge-prev)
 145     ("r" . smerge-resolve)
 146     ("a" . smerge-keep-all)
 147     ("b" . smerge-keep-base)
 148     ("o" . smerge-keep-other)
 149     ("m" . smerge-keep-mine)
 150     ("E" . smerge-ediff)
 151     ("C" . smerge-combine-with-next)
 152     ("R" . smerge-refine)
 153     ("\C-m" . smerge-keep-current)
 154     ("=" . ,(make-sparse-keymap "Diff"))
 155     ("=<" "base-mine" . smerge-diff-base-mine)
 156     ("=>" "base-other" . smerge-diff-base-other)
 157     ("==" "mine-other" . smerge-diff-mine-other))
 158   "The base keymap for `smerge-mode'.")
 159
 160 (defcustom smerge-command-prefix "\C-c^"
 161   "Prefix for `smerge-mode' commands."
 162   :group 'smerge
 163   :type '(choice (string "\e") (string "\C-c^") (string "") string))
 164
 165 (easy-mmode-defmap smerge-mode-map
 166   `((,smerge-command-prefix . ,smerge-basic-map))
 167   "Keymap for `smerge-mode'.")
 168
 169 (defvar smerge-check-cache nil)
 170 (make-variable-buffer-local 'smerge-check-cache)
 171 (defun smerge-check (n)
 172   (condition-case nil
 173       (let ((state (cons (point) (buffer-modified-tick))))
 174         (unless (equal (cdr smerge-check-cache) state)
 175           (smerge-match-conflict)
 176           (setq smerge-check-cache (cons (match-data) state)))
 177         (nth (* 2 n) (car smerge-check-cache)))
 178     (error nil)))
 179
 180 (easy-menu-define smerge-mode-menu smerge-mode-map
 181   "Menu for `smerge-mode'."
 182   '("SMerge"
 183     ["Next" smerge-next :help "Go to next conflict"]
 184     ["Previous" smerge-prev :help "Go to previous conflict"]
 185     "--"
 186     ["Keep All" smerge-keep-all :help "Keep all three versions"
 187      :active (smerge-check 1)]
 188     ["Keep Current" smerge-keep-current :help "Use current (at point) version"
 189      :active (and (smerge-check 1) (> (smerge-get-current) 0))]
 190     "--"
 191     ["Revert to Base" smerge-keep-base :help "Revert to base version"
 192      :active (smerge-check 2)]
 193     ["Keep Other" smerge-keep-other :help "Keep `other' version"
 194      :active (smerge-check 3)]
 195     ["Keep Yours" smerge-keep-mine :help "Keep your version"
 196      :active (smerge-check 1)]
 197     "--"
 198     ["Diff Base/Mine" smerge-diff-base-mine
 199      :help "Diff `base' and `mine' for current conflict"
 200      :active (smerge-check 2)]
 201     ["Diff Base/Other" smerge-diff-base-other
 202      :help "Diff `base' and `other' for current conflict"
 203      :active (smerge-check 2)]
 204     ["Diff Mine/Other" smerge-diff-mine-other
 205      :help "Diff `mine' and `other' for current conflict"
 206      :active (smerge-check 1)]
 207     "--"
 208     ["Invoke Ediff" smerge-ediff
 209      :help "Use Ediff to resolve the conflicts"
 210      :active (smerge-check 1)]
 211     ["Auto Resolve" smerge-resolve
 212      :help "Try auto-resolution heuristics"
 213      :active (smerge-check 1)]
 214     ["Combine" smerge-combine-with-next
 215      :help "Combine current conflict with next"
 216      :active (smerge-check 1)]
 217     ))
 218
 219 (easy-menu-define smerge-context-menu nil
 220   "Context menu for mine area in `smerge-mode'."
 221   '(nil
 222     ["Keep Current" smerge-keep-current :help "Use current (at point) version"]
 223     ["Kill Current" smerge-kill-current :help "Remove current (at point) version"]
 224     ["Keep All" smerge-keep-all :help "Keep all three versions"]
 225     "---"
 226     ["More..." (popup-menu smerge-mode-menu) :help "Show full SMerge mode menu"]
 227     ))
 228
 229 (defconst smerge-font-lock-keywords
 230   '((smerge-find-conflict
 231      (1 smerge-mine-face prepend t)
 232      (2 smerge-base-face prepend t)
 233      (3 smerge-other-face prepend t)
 234      ;; FIXME: `keep' doesn't work right with syntactic fontification.
 235      (0 smerge-markers-face keep)
 236      (4 nil t t)
 237      (5 nil t t)))
 238   "Font lock patterns for `smerge-mode'.")
 239
 240 (defconst smerge-begin-re "^<<<<<<< \\(.*\\)\n")
 241 (defconst smerge-end-re "^>>>>>>> .*\n")
 242 (defconst smerge-base-re "^||||||| .*\n")
 243 (defconst smerge-other-re "^=======\n")
 244
 245 (defvar smerge-conflict-style nil
 246   "Keep track of which style of conflict is in use.
 247 Can be nil if the style is undecided, or else:
 248 - `diff3-E'
 249 - `diff3-A'")
 250
 251 ;; Compiler pacifiers
 252 (defvar font-lock-mode)
 253 (defvar font-lock-keywords)
 254
 255 ;;;;
 256 ;;;; Actual code
 257 ;;;;
 258
 259 ;; Define smerge-next and smerge-prev
 260 (easy-mmode-define-navigation smerge smerge-begin-re "conflict" nil nil
 261   (if smerge-auto-refine
 262       (condition-case nil (smerge-refine) (error nil))))
 263
 264 (defconst smerge-match-names ["conflict" "mine" "base" "other"])
 265
 266 (defun smerge-ensure-match (n)
 267   (unless (match-end n)
 268     (error "No `%s'" (aref smerge-match-names n))))
 269
 270 (defun smerge-auto-leave ()
 271   (when (and smerge-auto-leave
 272              (save-excursion (goto-char (point-min))
 273                              (not (re-search-forward smerge-begin-re nil t))))
 274     (when (and (listp buffer-undo-list) smerge-mode)
 275       (push (list 'apply 'smerge-mode 1) buffer-undo-list))
 276     (smerge-mode -1)))
 277
 278
 279 (defun smerge-keep-all ()
 280   "Concatenate all versions."
 281   (interactive)
 282   (smerge-match-conflict)
 283   (let ((mb2 (or (match-beginning 2) (point-max)))
 284         (me2 (or (match-end 2) (point-min))))
 285     (delete-region (match-end 3) (match-end 0))
 286     (delete-region (max me2 (match-end 1)) (match-beginning 3))
 287     (if (and (match-end 2) (/= (match-end 1) (match-end 3)))
 288         (delete-region (match-end 1) (match-beginning 2)))
 289     (delete-region (match-beginning 0) (min (match-beginning 1) mb2))
 290     (smerge-auto-leave)))
 291
 292 (defun smerge-keep-n (n)
 293   (smerge-remove-props (match-beginning 0) (match-end 0))
 294   ;; We used to use replace-match, but that did not preserve markers so well.
 295   (delete-region (match-end n) (match-end 0))
 296   (delete-region (match-beginning 0) (match-beginning n)))
 297
 298 (defun smerge-combine-with-next ()
 299   "Combine the current conflict with the next one."
 300   ;; `smerge-auto-combine' relies on the finish position (at the beginning
 301   ;; of the closing marker).
 302   (interactive)
 303   (smerge-match-conflict)
 304   (let ((ends nil))
 305     (dolist (i '(3 2 1 0))
 306       (push (if (match-end i) (copy-marker (match-end i) t)) ends))
 307     (setq ends (apply 'vector ends))
 308     (goto-char (aref ends 0))
 309     (if (not (re-search-forward smerge-begin-re nil t))
 310         (error "No next conflict")
 311       (smerge-match-conflict)
 312       (let ((match-data (mapcar (lambda (m) (if m (copy-marker m)))
 313                                 (match-data))))
 314         ;; First copy the in-between text in each alternative.
 315         (dolist (i '(1 2 3))
 316           (when (aref ends i)
 317             (goto-char (aref ends i))
 318             (insert-buffer-substring (current-buffer)
 319                                      (aref ends 0) (car match-data))))
 320         (delete-region (aref ends 0) (car match-data))
 321         ;; Then move the second conflict's alternatives into the first.
 322         (dolist (i '(1 2 3))
 323           (set-match-data match-data)
 324           (when (and (aref ends i) (match-end i))
 325             (goto-char (aref ends i))
 326             (insert-buffer-substring (current-buffer)
 327                                      (match-beginning i) (match-end i))))
 328         (delete-region (car match-data) (cadr match-data))
 329         ;; Free the markers.
 330         (dolist (m match-data) (if m (move-marker m nil)))
 331         (mapc (lambda (m) (if m (move-marker m nil))) ends)))))
 332
 333 (defvar smerge-auto-combine-max-separation 2
 334   "Max number of lines between conflicts that should be combined.")
 335
 336 (defun smerge-auto-combine ()
 337   "Automatically combine conflicts that are near each other."
 338   (interactive)
 339   (save-excursion
 340     (goto-char (point-min))
 341     (while (smerge-find-conflict)
 342       ;; 2 is 1 (default) + 1 (the begin markers).
 343       (while (save-excursion
 344                (smerge-find-conflict
 345                 (line-beginning-position
 346                  (+ 2 smerge-auto-combine-max-separation))))
 347         (forward-line -1)               ;Go back inside the conflict.
 348         (smerge-combine-with-next)
 349         (forward-line 1)                ;Move past the end of the conflict.
 350         ))))
 351
 352 (defvar smerge-resolve-function
 353   (lambda () (error "Don't know how to resolve"))
 354   "Mode-specific merge function.
 355 The function is called with zero or one argument (non-nil if the resolution
 356 function should only apply safe heuristics) and with the match data set
 357 according to `smerge-match-conflict'.")
 358 (add-to-list 'debug-ignored-errors "Don't know how to resolve")
 359
 360 (defvar smerge-text-properties
 361   `(help-echo "merge conflict: mouse-3 shows a menu"
 362     ;; mouse-face highlight
 363     keymap (keymap (down-mouse-3 . smerge-popup-context-menu))))
 364
 365 (defun smerge-remove-props (beg end)
 366   (remove-overlays beg end 'smerge 'refine)
 367   (remove-overlays beg end 'smerge 'conflict)
 368   ;; Now that we use overlays rather than text-properties, this function
 369   ;; does not cause refontification any more.  It can be seen very clearly
 370   ;; in buffers where jit-lock-contextually is not t, in which case deleting
 371   ;; the "<<<<<<< foobar" leading line leaves the rest of the conflict
 372   ;; highlighted as if it were still a valid conflict.  Note that in many
 373   ;; important cases (such as the previous example) we're actually called
 374   ;; during font-locking so inhibit-modification-hooks is non-nil, so we
 375   ;; can't just modify the buffer and expect font-lock to be triggered as in:
 376   ;; (put-text-property beg end 'smerge-force-highlighting nil)
 377   (let ((modified (buffer-modified-p)))
 378     (remove-text-properties beg end '(fontified nil))
 379     (restore-buffer-modified-p modified)))
 380
 381 (defun smerge-popup-context-menu (event)
 382   "Pop up the Smerge mode context menu under mouse."
 383   (interactive "e")
 384   (if (and smerge-mode
 385            (save-excursion (posn-set-point (event-end event)) (smerge-check 1)))
 386       (progn
 387         (posn-set-point (event-end event))
 388         (smerge-match-conflict)
 389         (let ((i (smerge-get-current))
 390               o)
 391           (if (<= i 0)
 392               ;; Out of range
 393               (popup-menu smerge-mode-menu)
 394             ;; Install overlay.
 395             (setq o (make-overlay (match-beginning i) (match-end i)))
 396             (unwind-protect
 397                 (progn
 398                   (overlay-put o 'face 'highlight)
 399                   (sit-for 0)           ;Display the new highlighting.
 400                   (popup-menu smerge-context-menu))
 401               ;; Delete overlay.
 402               (delete-overlay o)))))
 403     ;; There's no conflict at point, the text-props are just obsolete.
 404     (save-excursion
 405       (let ((beg (re-search-backward smerge-end-re nil t))
 406             (end (re-search-forward smerge-begin-re nil t)))
 407         (smerge-remove-props (or beg (point-min)) (or end (point-max)))
 408         (push event unread-command-events)))))
 409
 410 (defun smerge-apply-resolution-patch (buf m0b m0e m3b m3e &optional m2b)
 411   "Replace the conflict with a bunch of subconflicts.
 412 BUF contains a plain diff between match-1 and match-3."
 413   (let ((line 1)
 414         (textbuf (current-buffer))
 415         (name1 (progn (goto-char m0b)
 416                       (buffer-substring (+ (point) 8) (line-end-position))))
 417         (name2 (when m2b (goto-char m2b) (forward-line -1)
 418                      (buffer-substring (+ (point) 8) (line-end-position))))
 419         (name3 (progn (goto-char m0e) (forward-line -1)
 420                       (buffer-substring (+ (point) 8) (line-end-position)))))
 421     (smerge-remove-props m0b m0e)
 422     (delete-region m3e m0e)
 423     (delete-region m0b m3b)
 424     (setq m3b m0b)
 425     (setq m3e (- m3e (- m3b m0b)))
 426     (goto-char m3b)
 427     (with-current-buffer buf
 428       (goto-char (point-min))
 429       (while (not (eobp))
 430         (if (not (looking-at "\\([0-9]+\\)\\(?:,\\([0-9]+\\)\\)?\\([acd]\\)\\([0-9]+\\)\\(?:,\\([0-9]+\\)\\)?$"))
 431             (error "Unexpected patch hunk header: %s"
 432                    (buffer-substring (point) (line-end-position)))
 433           (let* ((op (char-after (match-beginning 3)))
 434                  (startline (+ (string-to-number (match-string 1))
 435                                ;; No clue why this is the way it is, but line
 436                                ;; numbers seem to be off-by-one for `a' ops.
 437                                (if (eq op ?a) 1 0)))
 438                  (endline (if (eq op ?a) startline
 439                             (1+ (if (match-end 2)
 440                                     (string-to-number (match-string 2))
 441                                   startline))))
 442                  (lines (- endline startline))
 443                  (otherlines (cond
 444                               ((eq op ?d) nil)
 445                               ((null (match-end 5)) 1)
 446                               (t (- (string-to-number (match-string 5))
 447                                     (string-to-number (match-string 4)) -1))))
 448                  othertext)
 449             (forward-line 1)                             ;Skip header.
 450             (forward-line lines)                         ;Skip deleted text.
 451             (if (eq op ?c) (forward-line 1))             ;Skip separator.
 452             (setq othertext
 453                   (if (null otherlines) ""
 454                     (let ((pos (point)))
 455                       (dotimes (i otherlines) (delete-char 2) (forward-line 1))
 456                       (buffer-substring pos (point)))))
 457             (with-current-buffer textbuf
 458               (forward-line (- startline line))
 459               (insert "<<<<<<< " name1 "\n" othertext
 460                       (if name2 (concat "||||||| " name2))
 461                       "=======\n")
 462               (forward-line lines)
 463               (insert ">>>>>>> " name3 "\n")
 464               (setq line endline))))))))
 465
 466 (defun smerge-resolve (&optional safe)
 467   "Resolve the conflict at point intelligently.
 468 This relies on mode-specific knowledge and thus only works in
 469 some major modes.  Uses `smerge-resolve-function' to do the actual work."
 470   (interactive)
 471   (smerge-match-conflict)
 472   (smerge-remove-props (match-beginning 0) (match-end 0))
 473   (let ((md (match-data))
 474         (m0b (match-beginning 0))
 475         (m1b (match-beginning 1))
 476         (m2b (match-beginning 2))
 477         (m3b (match-beginning 3))
 478         (m0e (match-end 0))
 479         (m1e (match-end 1))
 480         (m2e (match-end 2))
 481         (m3e (match-end 3))
 482         (buf (generate-new-buffer " *smerge*"))
 483         m b o)
 484     (unwind-protect
 485         (progn
 486           (cond
 487            ;; Trivial diff3 -A non-conflicts.
 488            ((and (eq (match-end 1) (match-end 3))
 489                  (eq (match-beginning 1) (match-beginning 3)))
 490             (smerge-keep-n 3))
 491            ;; Mode-specific conflict resolution.
 492            ((condition-case nil
 493                 (atomic-change-group
 494                   (if safe
 495                       (funcall smerge-resolve-function safe)
 496                     (funcall smerge-resolve-function))
 497                   t)
 498               (error nil))
 499             ;; Nothing to do: the resolution function has done it already.
 500             nil)
 501            ;; "Mere whitespace" conflicts.
 502            ((or (and (eq m1e m3e) (eq m1b m3b)) ;Non-conflict.
 503                 (progn
 504                   (setq m (make-temp-file "smm"))
 505                   (write-region m1b m1e m nil 'silent)
 506                   (setq o (make-temp-file "smo"))
 507                   (write-region m3b m3e o nil 'silent)
 508                   ;; Same patch applied on both sides, with whitespace changes.
 509                   (zerop (call-process diff-command nil nil nil "-b" m o)))
 510                 (when m2e
 511                   (setq b (make-temp-file "smb"))
 512                   (write-region m2b m2e b nil 'silent)
 513                   ;; Only minor whitespace changes made locally.
 514                   (zerop (call-process diff-command nil buf nil "-bc" b m))))
 515             (set-match-data md)
 516             (smerge-keep-n 3))
 517            ;; Refine a 2-way conflict using "diff -b".
 518            ;; In case of a 3-way conflict with an empty base
 519            ;; (i.e. 2 conflicting additions), we do the same, presuming
 520            ;; that the 2 additions should be somehow merged rather
 521            ;; than concatenated.
 522            ((not (or (and m2b (not (eq m2b m2e)))
 523                      (eq m1b m1e) (eq m3b m3e)
 524                      (let ((lines (count-lines m3b m3e)))
 525                        (call-process diff-command nil buf nil "-b" o m)
 526                        (with-current-buffer buf
 527                          (goto-char (point-min))
 528                          ;; Make sure there's some refinement.
 529                          (looking-at
 530                           (concat "1," (number-to-string lines) "c"))))))
 531             (smerge-apply-resolution-patch buf m0b m0e m3b m3e m2b))
 532            ;; Try "diff -b BASE MINE | patch OTHER".
 533            ((when (and (not safe) m2e b
 534                        ;; If the BASE is empty, this would just concatenate
 535                        ;; the two, which is rarely right.
 536                        (not (eq m2b m2e)))
 537               (with-current-buffer buf
 538                 (zerop (call-process-region
 539                         (point-min) (point-max) "patch" t nil nil
 540                         "-r" "/dev/null" "--no-backup-if-mismatch"
 541                         "-fl" o))))
 542             (save-restriction
 543               (narrow-to-region m0b m0e)
 544               (smerge-remove-props m0b m0e)
 545               (insert-file-contents o nil nil nil t)))
 546            ;; Try "diff -b BASE OTHER | patch MINE".
 547            ((when (and (not safe) m2e b
 548                        ;; If the BASE is empty, this would just concatenate
 549                        ;; the two, which is rarely right.
 550                        (not (eq m2b m2e)))
 551               (write-region m3b m3e o nil 'silent)
 552               (call-process diff-command nil buf nil "-bc" b o)
 553               (with-current-buffer buf
 554                 (zerop (call-process-region
 555                         (point-min) (point-max) "patch" t nil nil
 556                         "-r" "/dev/null" "--no-backup-if-mismatch"
 557                         "-fl" m))))
 558             (save-restriction
 559               (narrow-to-region m0b m0e)
 560               (smerge-remove-props m0b m0e)
 561               (insert-file-contents m nil nil nil t)))
 562            (t
 563             (error "Don't know how to resolve"))))
 564       (if (buffer-name buf) (kill-buffer buf))
 565       (if m (delete-file m))
 566       (if b (delete-file b))
 567       (if o (delete-file o))))
 568   (smerge-auto-leave))
 569
 570 (defun smerge-resolve-all ()
 571   "Perform automatic resolution on all conflicts."
 572   (interactive)
 573   (save-excursion
 574     (goto-char (point-min))
 575     (while (re-search-forward smerge-begin-re nil t)
 576       (condition-case nil
 577           (progn
 578             (smerge-match-conflict)
 579             (smerge-resolve 'safe))
 580         (error nil)))))
 581
 582 (defun smerge-batch-resolve ()
 583   ;; command-line-args-left is what is left of the command line.
 584   (if (not noninteractive)
 585       (error "`smerge-batch-resolve' is to be used only with -batch"))
 586   (while command-line-args-left
 587     (let ((file (pop command-line-args-left)))
 588       (if (string-match "\\.rej\\'" file)
 589           ;; .rej files should never contain diff3 markers, on the other hand,
 590           ;; in Arch, .rej files are sometimes used to indicate that the
 591           ;; main file has diff3 markers.  So you can pass **/*.rej and
 592           ;; it will DTRT.
 593           (setq file (substring file 0 (match-beginning 0))))
 594       (message "Resolving conflicts in %s..." file)
 595       (when (file-readable-p file)
 596         (with-current-buffer (find-file-noselect file)
 597           (smerge-resolve-all)
 598           (save-buffer)
 599           (kill-buffer (current-buffer)))))))
 600
 601 (defun smerge-keep-base ()
 602   "Revert to the base version."
 603   (interactive)
 604   (smerge-match-conflict)
 605   (smerge-ensure-match 2)
 606   (smerge-keep-n 2)
 607   (smerge-auto-leave))
 608
 609 (defun smerge-keep-other ()
 610   "Use \"other\" version."
 611   (interactive)
 612   (smerge-match-conflict)
 613   ;;(smerge-ensure-match 3)
 614   (smerge-keep-n 3)
 615   (smerge-auto-leave))
 616
 617 (defun smerge-keep-mine ()
 618   "Keep your version."
 619   (interactive)
 620   (smerge-match-conflict)
 621   ;;(smerge-ensure-match 1)
 622   (smerge-keep-n 1)
 623   (smerge-auto-leave))
 624
 625 (defun smerge-get-current ()
 626   (let ((i 3))
 627     (while (or (not (match-end i))
 628                (< (point) (match-beginning i))
 629                (>= (point) (match-end i)))
 630       (decf i))
 631     i))
 632
 633 (defun smerge-keep-current ()
 634   "Use the current (under the cursor) version."
 635   (interactive)
 636   (smerge-match-conflict)
 637   (let ((i (smerge-get-current)))
 638     (if (<= i 0) (error "Not inside a version")
 639       (smerge-keep-n i)
 640       (smerge-auto-leave))))
 641
 642 (defun smerge-kill-current ()
 643   "Remove the current (under the cursor) version."
 644   (interactive)
 645   (smerge-match-conflict)
 646   (let ((i (smerge-get-current)))
 647     (if (<= i 0) (error "Not inside a version")
 648       (let ((left nil))
 649         (dolist (n '(3 2 1))
 650           (if (and (match-end n) (/= (match-end n) (match-end i)))
 651               (push n left)))
 652         (if (and (cdr left)
 653                  (/= (match-end (car left)) (match-end (cadr left))))
 654             (ding)                      ;We don't know how to do that.
 655           (smerge-keep-n (car left))
 656           (smerge-auto-leave))))))
 657
 658 (defun smerge-diff-base-mine ()
 659   "Diff 'base' and 'mine' version in current conflict region."
 660   (interactive)
 661   (smerge-diff 2 1))
 662
 663 (defun smerge-diff-base-other ()
 664   "Diff 'base' and 'other' version in current conflict region."
 665   (interactive)
 666   (smerge-diff 2 3))
 667
 668 (defun smerge-diff-mine-other ()
 669   "Diff 'mine' and 'other' version in current conflict region."
 670   (interactive)
 671   (smerge-diff 1 3))
 672
 673 (defun smerge-match-conflict ()
 674   "Get info about the conflict.  Puts the info in the `match-data'.
 675 The submatches contain:
 676  0:  the whole conflict.
 677  1:  your code.
 678  2:  the base code.
 679  3:  other code.
 680 An error is raised if not inside a conflict."
 681   (save-excursion
 682     (condition-case nil
 683         (let* ((orig-point (point))
 684
 685                (_ (forward-line 1))
 686                (_ (re-search-backward smerge-begin-re))
 687
 688                (start (match-beginning 0))
 689                (mine-start (match-end 0))
 690                (filename (or (match-string 1) ""))
 691
 692                (_ (re-search-forward smerge-end-re))
 693                (_ (assert (< orig-point (match-end 0))))
 694
 695                (other-end (match-beginning 0))
 696                (end (match-end 0))
 697
 698                (_ (re-search-backward smerge-other-re start))
 699
 700                (mine-end (match-beginning 0))
 701                (other-start (match-end 0))
 702
 703                base-start base-end)
 704
 705           ;; handle the various conflict styles
 706           (cond
 707            ((save-excursion
 708               (goto-char mine-start)
 709               (re-search-forward smerge-begin-re end t))
 710             ;; There's a nested conflict and we're after the the beginning
 711             ;; of the outer one but before the beginning of the inner one.
 712             ;; Of course, maybe this is not a nested conflict but in that
 713             ;; case it can only be something nastier that we don't know how
 714             ;; to handle, so may as well arbitrarily decide to treat it as
 715             ;; a nested conflict.  --Stef
 716             (error "There is a nested conflict"))
 717
 718            ((re-search-backward smerge-base-re start t)
 719             ;; a 3-parts conflict
 720             (set (make-local-variable 'smerge-conflict-style) 'diff3-A)
 721             (setq base-end mine-end)
 722             (setq mine-end (match-beginning 0))
 723             (setq base-start (match-end 0)))
 724
 725            ((string= filename (file-name-nondirectory
 726                                (or buffer-file-name "")))
 727             ;; a 2-parts conflict
 728             (set (make-local-variable 'smerge-conflict-style) 'diff3-E))
 729
 730            ((and (not base-start)
 731                  (or (eq smerge-conflict-style 'diff3-A)
 732                      (equal filename "ANCESTOR")
 733                      (string-match "\\`[.0-9]+\\'" filename)))
 734             ;; a same-diff conflict
 735             (setq base-start mine-start)
 736             (setq base-end   mine-end)
 737             (setq mine-start other-start)
 738             (setq mine-end   other-end)))
 739
 740           (store-match-data (list start end
 741                                   mine-start mine-end
 742                                   base-start base-end
 743                                   other-start other-end
 744                                   (when base-start (1- base-start)) base-start
 745                                   (1- other-start) other-start))
 746           t)
 747       (search-failed (error "Point not in conflict region")))))
 748
 749 (add-to-list 'debug-ignored-errors "Point not in conflict region")
 750
 751 (defun smerge-conflict-overlay (pos)
 752   "Return the conflict overlay at POS if any."
 753   (let ((ols (overlays-at pos))
 754         conflict)
 755     (dolist (ol ols)
 756       (if (and (eq (overlay-get ol 'smerge) 'conflict)
 757                (> (overlay-end ol) pos))
 758           (setq conflict ol)))
 759     conflict))
 760
 761 (defun smerge-find-conflict (&optional limit)
 762   "Find and match a conflict region.  Intended as a font-lock MATCHER.
 763 The submatches are the same as in `smerge-match-conflict'.
 764 Returns non-nil if a match is found between point and LIMIT.
 765 Point is moved to the end of the conflict."
 766   (let ((found nil)
 767         (pos (point))
 768         conflict)
 769     ;; First check to see if point is already inside a conflict, using
 770     ;; the conflict overlays.
 771     (while (and (not found) (setq conflict (smerge-conflict-overlay pos)))
 772       ;; Check the overlay's validity and kill it if it's out of date.
 773       (condition-case nil
 774           (progn
 775             (goto-char (overlay-start conflict))
 776             (smerge-match-conflict)
 777             (goto-char (match-end 0))
 778             (if (<= (point) pos)
 779                 (error "Matching backward!")
 780               (setq found t)))
 781         (error (smerge-remove-props
 782                 (overlay-start conflict) (overlay-end conflict))
 783                (goto-char pos))))
 784     ;; If we're not already inside a conflict, look for the next conflict
 785     ;; and add/update its overlay.
 786     (while (and (not found) (re-search-forward smerge-begin-re limit t))
 787       (condition-case nil
 788           (progn
 789             (smerge-match-conflict)
 790             (goto-char (match-end 0))
 791             (let ((conflict (smerge-conflict-overlay (1- (point)))))
 792               (if conflict
 793                   ;; Update its location, just in case it got messed up.
 794                   (move-overlay conflict (match-beginning 0) (match-end 0))
 795                 (setq conflict (make-overlay (match-beginning 0) (match-end 0)
 796                                              nil 'front-advance nil))
 797                 (overlay-put conflict 'evaporate t)
 798                 (overlay-put conflict 'smerge 'conflict)
 799                 (let ((props smerge-text-properties))
 800                   (while props
 801                     (overlay-put conflict (pop props) (pop props))))))
 802             (setq found t))
 803         (error nil)))
 804     found))
 805
 806 ;;; Refined change highlighting
 807
 808 (defvar smerge-refine-forward-function 'smerge-refine-forward
 809   "Function used to determine an \"atomic\" element.
 810 You can set it to `forward-char' to get char-level granularity.
 811 Its behavior has mainly two restrictions:
 812 - if this function encounters a newline, it's important that it stops right
 813   after the newline.
 814   This only matters if `smerge-refine-ignore-whitespace' is nil.
 815 - it needs to be unaffected by changes performed by the `preproc' argument
 816   to `smerge-refine-subst'.
 817   This only matters if `smerge-refine-weight-hack' is nil.")
 818
 819 (defvar smerge-refine-ignore-whitespace t
 820   "If non-nil,Indicate that smerge-refine should try to ignore change in whitespace.")
 821
 822 (defvar smerge-refine-weight-hack t
 823   "If non-nil, pass to diff as many lines as there are chars in the region.
 824 I.e. each atomic element (e.g. word) will be copied as many times (on different
 825 lines) as it has chars.  This has 2 advantages:
 826 - if `diff' tries to minimize the number *lines* (rather than chars)
 827   added/removed, this adjust the weights so that adding/removing long
 828   symbols is considered correspondingly more costly.
 829 - `smerge-refine-forward-function' only needs to be called when chopping up
 830   the regions, and `forward-char' can be used afterwards.
 831 It has the following disadvantages:
 832 - cannot use `diff -w' because the weighting causes added spaces in a line
 833   to be represented as added copies of some line, so `diff -w' can't do the
 834   right thing any more.
 835 - may in degenerate cases take a 1KB input region and turn it into a 1MB
 836   file to pass to diff.")
 837
 838 (defun smerge-refine-forward (n)
 839   (let ((case-fold-search nil)
 840         (re "[[:upper:]]?[[:lower:]]+\\|[[:upper:]]+\\|[[:digit:]]+\\|.\\|\n"))
 841     (when (and smerge-refine-ignore-whitespace
 842                ;; smerge-refine-weight-hack causes additional spaces to
 843                ;; appear as additional lines as well, so even if diff ignore
 844                ;; whitespace changes, it'll report added/removed lines :-(
 845                (not smerge-refine-weight-hack))
 846       (setq re (concat "[ \t]*\\(?:" re "\\)")))
 847     (dotimes (i n)
 848       (unless (looking-at re) (error "Smerge refine internal error"))
 849       (goto-char (match-end 0)))))
 850
 851 (defun smerge-refine-chopup-region (beg end file &optional preproc)
 852   "Chopup the region into small elements, one per line.
 853 Save the result into FILE.
 854 If non-nil, PREPROC is called with no argument in a buffer that contains
 855 a copy of the text, just before chopping it up.  It can be used to replace
 856 chars to try and eliminate some spurious differences."
 857   ;; We used to chop up char-by-char rather than word-by-word like ediff
 858   ;; does.  It had the benefit of simplicity and very fine results, but it
 859   ;; often suffered from problem that diff would find correlations where
 860   ;; there aren't any, so the resulting "change" didn't make much sense.
 861   ;; You can still get this behavior by setting
 862   ;; `smerge-refine-forward-function' to `forward-char'.
 863   (let ((buf (current-buffer)))
 864     (with-temp-buffer
 865       (insert-buffer-substring buf beg end)
 866       (when preproc (goto-char (point-min)) (funcall preproc))
 867       (when smerge-refine-ignore-whitespace
 868         ;; It doesn't make much of a difference for diff-fine-highlight
 869         ;; because we still have the _/+/</>/! prefix anyway.  Can still be
 870         ;; useful in other circumstances.
 871         (subst-char-in-region (point-min) (point-max) ?\n ?\s))
 872       (goto-char (point-min))
 873       (while (not (eobp))
 874         (funcall smerge-refine-forward-function 1)
 875         (let ((s (if (prog2 (forward-char -1) (bolp) (forward-char 1))
 876                      nil
 877                    (buffer-substring (line-beginning-position) (point)))))
 878           ;; We add \n after each char except after \n, so we get
 879           ;; one line per text char, where each line contains
 880           ;; just one char, except for \n chars which are
 881           ;; represented by the empty line.
 882           (unless (eq (char-before) ?\n) (insert ?\n))
 883           ;; HACK ALERT!!
 884           (if smerge-refine-weight-hack
 885               (dotimes (i (1- (length s))) (insert s "\n")))))
 886       (unless (bolp) (error "Smerge refine internal error"))
 887       (let ((coding-system-for-write 'emacs-mule))
 888         (write-region (point-min) (point-max) file nil 'nomessage)))))
 889
 890 (defun smerge-refine-highlight-change (buf beg match-num1 match-num2 props)
 891   (with-current-buffer buf
 892     (goto-char beg)
 893     (let* ((startline (- (string-to-number match-num1) 1))
 894            (beg (progn (funcall (if smerge-refine-weight-hack
 895                                     'forward-char
 896                                   smerge-refine-forward-function)
 897                                 startline)
 898                        (point)))
 899            (end (progn (funcall (if smerge-refine-weight-hack
 900                                     'forward-char
 901                                   smerge-refine-forward-function)
 902                           (if match-num2
 903                               (- (string-to-number match-num2)
 904                                  startline)
 905                             1))
 906                        (point))))
 907       (when smerge-refine-ignore-whitespace
 908         (skip-chars-backward " \t\n" beg) (setq end (point))
 909         (goto-char beg)
 910         (skip-chars-forward " \t\n" end)  (setq beg (point)))
 911       (when (> end beg)
 912         (let ((ol (make-overlay
 913                    beg end nil
 914                    ;; Make them tend to shrink rather than spread when editing.
 915                    'front-advance nil)))
 916           (overlay-put ol 'evaporate t)
 917           (dolist (x props) (overlay-put ol (car x) (cdr x)))
 918           ol)))))
 919
 920 (defun smerge-refine-subst (beg1 end1 beg2 end2 props &optional preproc)
 921   "Show fine differences in the two regions BEG1..END1 and BEG2..END2.
 922 PROPS is an alist of properties to put (via overlays) on the changes.
 923 If non-nil, PREPROC is called with no argument in a buffer that contains
 924 a copy of a region, just before preparing it to for `diff'.  It can be used to
 925 replace chars to try and eliminate some spurious differences."
 926   (let* ((buf (current-buffer))
 927          (pos (point))
 928          (file1 (make-temp-file "diff1"))
 929          (file2 (make-temp-file "diff2")))
 930     ;; Chop up regions into smaller elements and save into files.
 931     (smerge-refine-chopup-region beg1 end1 file1 preproc)
 932     (smerge-refine-chopup-region beg2 end2 file2 preproc)
 933
 934     ;; Call diff on those files.
 935     (unwind-protect
 936         (with-temp-buffer
 937           (let ((coding-system-for-read 'emacs-mule))
 938             (call-process diff-command nil t nil
 939                           (if (and smerge-refine-ignore-whitespace
 940                                    (not smerge-refine-weight-hack))
 941                               ;; Pass -a so diff treats it as a text file even
 942                               ;; if it contains \0 and such.
 943                               ;; Pass -d so as to get the smallest change, but
 944                               ;; also and more importantly because otherwise it
 945                               ;; may happen that diff doesn't behave like
 946                               ;; smerge-refine-weight-hack expects it to.
 947                               ;; See http://thread.gmane.org/gmane.emacs.devel/82685.
 948                               "-awd" "-ad")
 949                           file1 file2))
 950           ;; Process diff's output.
 951           (goto-char (point-min))
 952           (let ((last1 nil)
 953                 (last2 nil))
 954             (while (not (eobp))
 955               (if (not (looking-at "\\([0-9]+\\)\\(?:,\\([0-9]+\\)\\)?\\([acd]\\)\\([0-9]+\\)\\(?:,\\([0-9]+\\)\\)?$"))
 956                   (error "Unexpected patch hunk header: %s"
 957                          (buffer-substring (point) (line-end-position))))
 958               (let ((op (char-after (match-beginning 3)))
 959                     (m1 (match-string 1))
 960                     (m2 (match-string 2))
 961                     (m4 (match-string 4))
 962                     (m5 (match-string 5)))
 963                 (when (memq op '(?d ?c))
 964                   (setq last1
 965                         (smerge-refine-highlight-change buf beg1 m1 m2 props)))
 966                 (when (memq op '(?a ?c))
 967                   (setq last2
 968                         (smerge-refine-highlight-change buf beg2 m4 m5 props))))
 969               (forward-line 1)                            ;Skip hunk header.
 970               (and (re-search-forward "^[0-9]" nil 'move) ;Skip hunk body.
 971                    (goto-char (match-beginning 0))))
 972             ;; (assert (or (null last1) (< (overlay-start last1) end1)))
 973             ;; (assert (or (null last2) (< (overlay-start last2) end2)))
 974             (if smerge-refine-weight-hack
 975                 (progn
 976                   ;; (assert (or (null last1) (<= (overlay-end last1) end1)))
 977                   ;; (assert (or (null last2) (<= (overlay-end last2) end2)))
 978                   )
 979               ;; smerge-refine-forward-function when calling in chopup may
 980               ;; have stopped because it bumped into EOB whereas in
 981               ;; smerge-refine-weight-hack it may go a bit further.
 982               (if (and last1 (> (overlay-end last1) end1))
 983                   (move-overlay last1 (overlay-start last1) end1))
 984               (if (and last2 (> (overlay-end last2) end2))
 985                   (move-overlay last2 (overlay-start last2) end2))
 986               )))
 987       (goto-char pos)
 988       (delete-file file1)
 989       (delete-file file2))))
 990
 991 (defun smerge-refine (&optional part)
 992   "Highlight the words of the conflict that are different.
 993 For 3-way conflicts, highlights only 2 of the 3 parts.
 994 A numeric argument PART can be used to specify which 2 parts;
 995 repeating the command will highlight other 2 parts."
 996   (interactive
 997    (if (integerp current-prefix-arg) (list current-prefix-arg)
 998      (smerge-match-conflict)
 999      (let* ((prop (get-text-property (match-beginning 0) 'smerge-refine-part))
1000             (part (if (and (consp prop)
1001                            (eq (buffer-chars-modified-tick) (car prop)))
1002                       (cdr prop))))
1003        ;; If already highlighted, cycle.
1004        (list (if (integerp part) (1+ (mod part 3)))))))
1005
1006   (if (and (integerp part) (or (< part 1) (> part 3)))
1007       (error "No conflict part nb %s" part))
1008   (smerge-match-conflict)
1009   (remove-overlays (match-beginning 0) (match-end 0) 'smerge 'refine)
1010   ;; Ignore `part' if not applicable, and default it if not provided.
1011   (setq part (cond ((null (match-end 2)) 2)
1012                    ((eq (match-end 1) (match-end 3)) 1)
1013                    ((integerp part) part)
1014                    (t 2)))
1015   (let ((n1 (if (eq part 1) 2 1))
1016         (n2 (if (eq part 3) 2 3)))
1017     (smerge-ensure-match n1)
1018     (smerge-ensure-match n2)
1019     (put-text-property (match-beginning 0) (1+ (match-beginning 0))
1020                        'smerge-refine-part
1021                        (cons (buffer-chars-modified-tick) part))
1022     (smerge-refine-subst (match-beginning n1) (match-end n1)
1023                          (match-beginning n2)  (match-end n2)
1024                          '((smerge . refine)
1025                            (face . smerge-refined-change)))))
1026
1027 (defun smerge-diff (n1 n2)
1028   (smerge-match-conflict)
1029   (smerge-ensure-match n1)
1030   (smerge-ensure-match n2)
1031   (let ((name1 (aref smerge-match-names n1))
1032         (name2 (aref smerge-match-names n2))
1033         ;; Read them before the match-data gets clobbered.
1034         (beg1 (match-beginning n1))
1035         (end1 (match-end n1))
1036         (beg2 (match-beginning n2))
1037         (end2 (match-end n2))
1038         (file1 (make-temp-file "smerge1"))
1039         (file2 (make-temp-file "smerge2"))
1040         (dir default-directory)
1041         (file (if buffer-file-name (file-relative-name buffer-file-name)))
1042         ;; We would want to use `emacs-mule-unix' for read&write, but we
1043         ;; bump into problems with the coding-system used by diff to write
1044         ;; the file names and the time stamps in the header.
1045         ;; `buffer-file-coding-system' is not always correct either, but if
1046         ;; the OS/user uses only one coding-system, then it works.
1047         (coding-system-for-read buffer-file-coding-system))
1048     (write-region beg1 end1 file1 nil 'nomessage)
1049     (write-region beg2 end2 file2 nil 'nomessage)
1050     (unwind-protect
1051         (with-current-buffer (get-buffer-create smerge-diff-buffer-name)
1052           (setq default-directory dir)
1053           (let ((inhibit-read-only t))
1054             (erase-buffer)
1055             (let ((status
1056                    (apply 'call-process diff-command nil t nil
1057                           (append smerge-diff-switches
1058                                   (list "-L" (concat name1 "/" file)
1059                                         "-L" (concat name2 "/" file)
1060                                         file1 file2)))))
1061               (if (eq status 0) (insert "No differences found.\n"))))
1062           (goto-char (point-min))
1063           (diff-mode)
1064           (display-buffer (current-buffer) t))
1065       (delete-file file1)
1066       (delete-file file2))))
1067
1068 ;; compiler pacifiers
1069 (defvar smerge-ediff-windows)
1070 (defvar smerge-ediff-buf)
1071 (defvar ediff-buffer-A)
1072 (defvar ediff-buffer-B)
1073 (defvar ediff-buffer-C)
1074 (defvar ediff-ancestor-buffer)
1075 (defvar ediff-quit-hook)
1076 (declare-function ediff-cleanup-mess "ediff-util" nil)
1077
1078 ;;;###autoload
1079 (defun smerge-ediff (&optional name-mine name-other name-base)
1080   "Invoke ediff to resolve the conflicts.
1081 NAME-MINE, NAME-OTHER, and NAME-BASE, if non-nil, are used for the
1082 buffer names."
1083   (interactive)
1084   (let* ((buf (current-buffer))
1085          (mode major-mode)
1086          ;;(ediff-default-variant 'default-B)
1087          (config (current-window-configuration))
1088          (filename (file-name-nondirectory buffer-file-name))
1089          (mine (generate-new-buffer
1090                 (or name-mine (concat "*" filename " MINE*"))))
1091          (other (generate-new-buffer
1092                  (or name-other (concat "*" filename " OTHER*"))))
1093          base)
1094     (with-current-buffer mine
1095       (buffer-disable-undo)
1096       (insert-buffer-substring buf)
1097       (goto-char (point-min))
1098       (while (smerge-find-conflict)
1099         (when (match-beginning 2) (setq base t))
1100         (smerge-keep-n 1))
1101       (buffer-enable-undo)
1102       (set-buffer-modified-p nil)
1103       (funcall mode))
1104
1105     (with-current-buffer other
1106       (buffer-disable-undo)
1107       (insert-buffer-substring buf)
1108       (goto-char (point-min))
1109       (while (smerge-find-conflict)
1110         (smerge-keep-n 3))
1111       (buffer-enable-undo)
1112       (set-buffer-modified-p nil)
1113       (funcall mode))
1114
1115     (when base
1116       (setq base (generate-new-buffer
1117                   (or name-base (concat "*" filename " BASE*"))))
1118       (with-current-buffer base
1119         (buffer-disable-undo)
1120         (insert-buffer-substring buf)
1121         (goto-char (point-min))
1122         (while (smerge-find-conflict)
1123           (if (match-end 2)
1124               (smerge-keep-n 2)
1125             (delete-region (match-beginning 0) (match-end 0))))
1126         (buffer-enable-undo)
1127         (set-buffer-modified-p nil)
1128         (funcall mode)))
1129
1130     ;; the rest of the code is inspired from vc.el
1131     ;; Fire up ediff.
1132     (set-buffer
1133      (if base
1134          (ediff-merge-buffers-with-ancestor mine other base)
1135           ;; nil 'ediff-merge-revisions-with-ancestor buffer-file-name)
1136        (ediff-merge-buffers mine other)))
1137         ;; nil 'ediff-merge-revisions buffer-file-name)))
1138
1139     ;; Ediff is now set up, and we are in the control buffer.
1140     ;; Do a few further adjustments and take precautions for exit.
1141     (set (make-local-variable 'smerge-ediff-windows) config)
1142     (set (make-local-variable 'smerge-ediff-buf) buf)
1143     (set (make-local-variable 'ediff-quit-hook)
1144          (lambda ()
1145            (let ((buffer-A ediff-buffer-A)
1146                  (buffer-B ediff-buffer-B)
1147                  (buffer-C ediff-buffer-C)
1148                  (buffer-Ancestor ediff-ancestor-buffer)
1149                  (buf smerge-ediff-buf)
1150                  (windows smerge-ediff-windows))
1151              (ediff-cleanup-mess)
1152              (with-current-buffer buf
1153                (erase-buffer)
1154                (insert-buffer-substring buffer-C)
1155                (kill-buffer buffer-A)
1156                (kill-buffer buffer-B)
1157                (kill-buffer buffer-C)
1158                (when (bufferp buffer-Ancestor) (kill-buffer buffer-Ancestor))
1159                (set-window-configuration windows)
1160                (message "Conflict resolution finished; you may save the buffer")))))
1161     (message "Please resolve conflicts now; exit ediff when done")))
1162
1163 (defun smerge-makeup-conflict (pt1 pt2 pt3 &optional pt4)
1164   "Insert diff3 markers to make a new conflict.
1165 Uses point and mark for 2 of the relevant positions and previous marks
1166 for the other ones.
1167 By default, makes up a 2-way conflict,
1168 with a \\[universal-argument] prefix, makes up a 3-way conflict."
1169   (interactive
1170    (list (point)
1171          (mark)
1172          (progn (pop-mark) (mark))
1173          (when current-prefix-arg (pop-mark) (mark))))
1174   ;; Start from the end so as to avoid problems with pos-changes.
1175   (destructuring-bind (pt1 pt2 pt3 &optional pt4)
1176       (sort (list* pt1 pt2 pt3 (if pt4 (list pt4))) '>=)
1177     (goto-char pt1) (beginning-of-line)
1178     (insert ">>>>>>> OTHER\n")
1179     (goto-char pt2) (beginning-of-line)
1180     (insert "=======\n")
1181     (goto-char pt3) (beginning-of-line)
1182     (when pt4
1183       (insert "||||||| BASE\n")
1184       (goto-char pt4) (beginning-of-line))
1185     (insert "<<<<<<< MINE\n"))
1186   (if smerge-mode nil (smerge-mode 1))
1187   (smerge-refine))
1188
1189
1190 (defconst smerge-parsep-re
1191   (concat smerge-begin-re "\\|" smerge-end-re "\\|"
1192           smerge-base-re "\\|" smerge-other-re "\\|"))
1193
1194 ;;;###autoload
1195 (define-minor-mode smerge-mode
1196   "Minor mode to simplify editing output from the diff3 program.
1197 \\{smerge-mode-map}"
1198   :group 'smerge :lighter " SMerge"
1199   (when (and (boundp 'font-lock-mode) font-lock-mode)
1200     (save-excursion
1201       (if smerge-mode
1202           (font-lock-add-keywords nil smerge-font-lock-keywords 'append)
1203         (font-lock-remove-keywords nil smerge-font-lock-keywords))
1204       (goto-char (point-min))
1205       (while (smerge-find-conflict)
1206         (save-excursion
1207           (font-lock-fontify-region (match-beginning 0) (match-end 0) nil)))))
1208   (if (string-match (regexp-quote smerge-parsep-re) paragraph-separate)
1209       (unless smerge-mode
1210         (set (make-local-variable 'paragraph-separate)
1211              (replace-match "" t t paragraph-separate)))
1212     (when smerge-mode
1213         (set (make-local-variable 'paragraph-separate)
1214              (concat smerge-parsep-re paragraph-separate))))
1215   (unless smerge-mode
1216     (smerge-remove-props (point-min) (point-max))))
1217
1218 ;;;###autoload
1219 (defun smerge-start-session ()
1220   "Turn on `smerge-mode' and move point to first conflict marker.
1221 If no conflict maker is found, turn off `smerge-mode'."
1222   (smerge-mode 1)
1223   (condition-case nil
1224       (smerge-next)
1225     (error (smerge-auto-leave))))
1226
1227 (provide 'smerge-mode)
1228
1229 ;; arch-tag: 605c8d1e-e43d-4943-a6f3-1bcc4333e690
1230 ;;; smerge-mode.el ends here