lisp/smerge-mode.el

   1 ;;; smerge-mode.el --- Minor mode to resolve diff3 conflicts
   2
   3 ;; Copyright (C) 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2006,
   4 ;;   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 of the License, or
  14 ;; (at your option) 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.  If not, see <http://www.gnu.org/licenses/>.
  23
  24 ;;; Commentary:
  25
  26 ;; Provides a lightweight alternative to emerge/ediff.
  27 ;; To use it, simply add to your .emacs the following lines:
  28 ;;
  29 ;;   (autoload 'smerge-mode "smerge-mode" nil t)
  30 ;;
  31 ;; you can even have it turned on automatically with the following
  32 ;; piece of code in your .emacs:
  33 ;;
  34 ;;   (defun sm-try-smerge ()
  35 ;;     (save-excursion
  36 ;;       (goto-char (point-min))
  37 ;;       (when (re-search-forward "^<<<<<<< " nil t)
  38 ;;         (smerge-mode 1))))
  39 ;;   (add-hook 'find-file-hook 'sm-try-smerge t)
  40
  41 ;;; Todo:
  42
  43 ;; - if requested, ask the user whether he wants to call ediff right away
  44
  45 ;;; Code:
  46
  47 (eval-when-compile (require 'cl))
  48 (require 'diff-mode)                    ;For diff-auto-refine-mode.
  49
  50
  51 ;;; The real definition comes later.
  52 (defvar smerge-mode)
  53
  54 (defgroup smerge ()
  55   "Minor mode to highlight and resolve diff3 conflicts."
  56   :group 'tools
  57   :prefix "smerge-")
  58
  59 (defcustom smerge-diff-buffer-name "*vc-diff*"
  60   "Buffer name to use for displaying diffs."
  61   :group 'smerge
  62   :type '(choice
  63           (const "*vc-diff*")
  64           (const "*cvs-diff*")
  65           (const "*smerge-diff*")
  66           string))
  67
  68 (defcustom smerge-diff-switches
  69   (append '("-d" "-b")
  70           (if (listp diff-switches) diff-switches (list diff-switches)))
  71   "A list of strings specifying switches to be passed to diff.
  72 Used in `smerge-diff-base-mine' and related functions."
  73   :group 'smerge
  74   :type '(repeat string))
  75
  76 (defcustom smerge-auto-leave t
  77   "Non-nil means to leave `smerge-mode' when the last conflict is resolved."
  78   :group 'smerge
  79   :type 'boolean)
  80
  81 (defface smerge-mine
  82   '((((min-colors 88) (background light))
  83      (:foreground "blue1"))
  84     (((background light))
  85      (:foreground "blue"))
  86     (((min-colors 88) (background dark))
  87      (:foreground "cyan1"))
  88     (((background dark))
  89      (:foreground "cyan")))
  90   "Face for your code."
  91   :group 'smerge)
  92 ;; backward-compatibility alias
  93 (put 'smerge-mine-face 'face-alias 'smerge-mine)
  94 (defvar smerge-mine-face 'smerge-mine)
  95
  96 (defface smerge-other
  97   '((((background light))
  98      (:foreground "darkgreen"))
  99     (((background dark))
 100      (:foreground "lightgreen")))
 101   "Face for the other code."
 102   :group 'smerge)
 103 ;; backward-compatibility alias
 104 (put 'smerge-other-face 'face-alias 'smerge-other)
 105 (defvar smerge-other-face 'smerge-other)
 106
 107 (defface smerge-base
 108   '((((min-colors 88) (background light))
 109      (:foreground "red1"))
 110     (((background light))
 111      (:foreground "red"))
 112     (((background dark))
 113      (:foreground "orange")))
 114   "Face for the base code."
 115   :group 'smerge)
 116 ;; backward-compatibility alias
 117 (put 'smerge-base-face 'face-alias 'smerge-base)
 118 (defvar smerge-base-face 'smerge-base)
 119
 120 (defface smerge-markers
 121   '((((background light))
 122      (:background "grey85"))
 123     (((background dark))
 124      (:background "grey30")))
 125   "Face for the conflict markers."
 126   :group 'smerge)
 127 ;; backward-compatibility alias
 128 (put 'smerge-markers-face 'face-alias 'smerge-markers)
 129 (defvar smerge-markers-face 'smerge-markers)
 130
 131 (defface smerge-refined-change
 132   '((t :background "yellow"))
 133   "Face used for char-based changes shown by `smerge-refine'."
 134   :group 'smerge)
 135
 136 (easy-mmode-defmap smerge-basic-map
 137   `(("n" . smerge-next)
 138     ("p" . smerge-prev)
 139     ("r" . smerge-resolve)
 140     ("a" . smerge-keep-all)
 141     ("b" . smerge-keep-base)
 142     ("o" . smerge-keep-other)
 143     ("m" . smerge-keep-mine)
 144     ("E" . smerge-ediff)
 145     ("C" . smerge-combine-with-next)
 146     ("R" . smerge-refine)
 147     ("\C-m" . smerge-keep-current)
 148     ("=" . ,(make-sparse-keymap "Diff"))
 149     ("=<" "base-mine" . smerge-diff-base-mine)
 150     ("=>" "base-other" . smerge-diff-base-other)
 151     ("==" "mine-other" . smerge-diff-mine-other))
 152   "The base keymap for `smerge-mode'.")
 153
 154 (defcustom smerge-command-prefix "\C-c^"
 155   "Prefix for `smerge-mode' commands."
 156   :group 'smerge
 157   :type '(choice (const :tag "ESC"   "\e")
 158                  (const :tag "C-c ^" "\C-c^" )
 159                  (const :tag "none"  "")
 160                  string))
 161
 162 (easy-mmode-defmap smerge-mode-map
 163   `((,smerge-command-prefix . ,smerge-basic-map))
 164   "Keymap for `smerge-mode'.")
 165
 166 (defvar smerge-check-cache nil)
 167 (make-variable-buffer-local 'smerge-check-cache)
 168 (defun smerge-check (n)
 169   (condition-case nil
 170       (let ((state (cons (point) (buffer-modified-tick))))
 171         (unless (equal (cdr smerge-check-cache) state)
 172           (smerge-match-conflict)
 173           (setq smerge-check-cache (cons (match-data) state)))
 174         (nth (* 2 n) (car smerge-check-cache)))
 175     (error nil)))
 176
 177 (easy-menu-define smerge-mode-menu smerge-mode-map
 178   "Menu for `smerge-mode'."
 179   '("SMerge"
 180     ["Next" smerge-next :help "Go to next conflict"]
 181     ["Previous" smerge-prev :help "Go to previous conflict"]
 182     "--"
 183     ["Keep All" smerge-keep-all :help "Keep all three versions"
 184      :active (smerge-check 1)]
 185     ["Keep Current" smerge-keep-current :help "Use current (at point) version"
 186      :active (and (smerge-check 1) (> (smerge-get-current) 0))]
 187     "--"
 188     ["Revert to Base" smerge-keep-base :help "Revert to base version"
 189      :active (smerge-check 2)]
 190     ["Keep Other" smerge-keep-other :help "Keep `other' version"
 191      :active (smerge-check 3)]
 192     ["Keep Yours" smerge-keep-mine :help "Keep your version"
 193      :active (smerge-check 1)]
 194     "--"
 195     ["Diff Base/Mine" smerge-diff-base-mine
 196      :help "Diff `base' and `mine' for current conflict"
 197      :active (smerge-check 2)]
 198     ["Diff Base/Other" smerge-diff-base-other
 199      :help "Diff `base' and `other' for current conflict"
 200      :active (smerge-check 2)]
 201     ["Diff Mine/Other" smerge-diff-mine-other
 202      :help "Diff `mine' and `other' for current conflict"
 203      :active (smerge-check 1)]
 204     "--"
 205     ["Invoke Ediff" smerge-ediff
 206      :help "Use Ediff to resolve the conflicts"
 207      :active (smerge-check 1)]
 208     ["Auto Resolve" smerge-resolve
 209      :help "Try auto-resolution heuristics"
 210      :active (smerge-check 1)]
 211     ["Combine" smerge-combine-with-next
 212      :help "Combine current conflict with next"
 213      :active (smerge-check 1)]
 214     ))
 215
 216 (easy-menu-define smerge-context-menu nil
 217   "Context menu for mine area in `smerge-mode'."
 218   '(nil
 219     ["Keep Current" smerge-keep-current :help "Use current (at point) version"]
 220     ["Kill Current" smerge-kill-current :help "Remove current (at point) version"]
 221     ["Keep All" smerge-keep-all :help "Keep all three versions"]
 222     "---"
 223     ["More..." (popup-menu smerge-mode-menu) :help "Show full SMerge mode menu"]
 224     ))
 225
 226 (defconst smerge-font-lock-keywords
 227   '((smerge-find-conflict
 228      (1 smerge-mine-face prepend t)
 229      (2 smerge-base-face prepend t)
 230      (3 smerge-other-face prepend t)
 231      ;; FIXME: `keep' doesn't work right with syntactic fontification.
 232      (0 smerge-markers-face keep)
 233      (4 nil t t)
 234      (5 nil t t)))
 235   "Font lock patterns for `smerge-mode'.")
 236
 237 (defconst smerge-begin-re "^<<<<<<< \\(.*\\)\n")
 238 (defconst smerge-end-re "^>>>>>>> .*\n")
 239 (defconst smerge-base-re "^||||||| .*\n")
 240 (defconst smerge-other-re "^=======\n")
 241
 242 (defvar smerge-conflict-style nil
 243   "Keep track of which style of conflict is in use.
 244 Can be nil if the style is undecided, or else:
 245 - `diff3-E'
 246 - `diff3-A'")
 247
 248 ;; Compiler pacifiers
 249 (defvar font-lock-mode)
 250 (defvar font-lock-keywords)
 251
 252 ;;;;
 253 ;;;; Actual code
 254 ;;;;
 255
 256 ;; Define smerge-next and smerge-prev
 257 (easy-mmode-define-navigation smerge smerge-begin-re "conflict" nil nil
 258   (if diff-auto-refine-mode
 259       (condition-case nil (smerge-refine) (error nil))))
 260
 261 (defconst smerge-match-names ["conflict" "mine" "base" "other"])
 262
 263 (defun smerge-ensure-match (n)
 264   (unless (match-end n)
 265     (error "No `%s'" (aref smerge-match-names n))))
 266
 267 (defun smerge-auto-leave ()
 268   (when (and smerge-auto-leave
 269              (save-excursion (goto-char (point-min))
 270                              (not (re-search-forward smerge-begin-re nil t))))
 271     (when (and (listp buffer-undo-list) smerge-mode)
 272       (push (list 'apply 'smerge-mode 1) buffer-undo-list))
 273     (smerge-mode -1)))
 274
 275
 276 (defun smerge-keep-all ()
 277   "Concatenate all versions."
 278   (interactive)
 279   (smerge-match-conflict)
 280   (let ((mb2 (or (match-beginning 2) (point-max)))
 281         (me2 (or (match-end 2) (point-min))))
 282     (delete-region (match-end 3) (match-end 0))
 283     (delete-region (max me2 (match-end 1)) (match-beginning 3))
 284     (if (and (match-end 2) (/= (match-end 1) (match-end 3)))
 285         (delete-region (match-end 1) (match-beginning 2)))
 286     (delete-region (match-beginning 0) (min (match-beginning 1) mb2))
 287     (smerge-auto-leave)))
 288
 289 (defun smerge-keep-n (n)
 290   (smerge-remove-props (match-beginning 0) (match-end 0))
 291   ;; We used to use replace-match, but that did not preserve markers so well.
 292   (delete-region (match-end n) (match-end 0))
 293   (delete-region (match-beginning 0) (match-beginning n)))
 294
 295 (defun smerge-combine-with-next ()
 296   "Combine the current conflict with the next one."
 297   ;; `smerge-auto-combine' relies on the finish position (at the beginning
 298   ;; of the closing marker).
 299   (interactive)
 300   (smerge-match-conflict)
 301   (let ((ends nil))
 302     (dolist (i '(3 2 1 0))
 303       (push (if (match-end i) (copy-marker (match-end i) t)) ends))
 304     (setq ends (apply 'vector ends))
 305     (goto-char (aref ends 0))
 306     (if (not (re-search-forward smerge-begin-re nil t))
 307         (error "No next conflict")
 308       (smerge-match-conflict)
 309       (let ((match-data (mapcar (lambda (m) (if m (copy-marker m)))
 310                                 (match-data))))
 311         ;; First copy the in-between text in each alternative.
 312         (dolist (i '(1 2 3))
 313           (when (aref ends i)
 314             (goto-char (aref ends i))
 315             (insert-buffer-substring (current-buffer)
 316                                      (aref ends 0) (car match-data))))
 317         (delete-region (aref ends 0) (car match-data))
 318         ;; Then move the second conflict's alternatives into the first.
 319         (dolist (i '(1 2 3))
 320           (set-match-data match-data)
 321           (when (and (aref ends i) (match-end i))
 322             (goto-char (aref ends i))
 323             (insert-buffer-substring (current-buffer)
 324                                      (match-beginning i) (match-end i))))
 325         (delete-region (car match-data) (cadr match-data))
 326         ;; Free the markers.
 327         (dolist (m match-data) (if m (move-marker m nil)))
 328         (mapc (lambda (m) (if m (move-marker m nil))) ends)))))
 329
 330 (defvar smerge-auto-combine-max-separation 2
 331   "Max number of lines between conflicts that should be combined.")
 332
 333 (defun smerge-auto-combine ()
 334   "Automatically combine conflicts that are near each other."
 335   (interactive)
 336   (save-excursion
 337     (goto-char (point-min))
 338     (while (smerge-find-conflict)
 339       ;; 2 is 1 (default) + 1 (the begin markers).
 340       (while (save-excursion
 341                (smerge-find-conflict
 342                 (line-beginning-position
 343                  (+ 2 smerge-auto-combine-max-separation))))
 344         (forward-line -1)               ;Go back inside the conflict.
 345         (smerge-combine-with-next)
 346         (forward-line 1)                ;Move past the end of the conflict.
 347         ))))
 348
 349 (defvar smerge-resolve-function
 350   (lambda () (error "Don't know how to resolve"))
 351   "Mode-specific merge function.
 352 The function is called with zero or one argument (non-nil if the resolution
 353 function should only apply safe heuristics) and with the match data set
 354 according to `smerge-match-conflict'.")
 355 (add-to-list 'debug-ignored-errors "Don't know how to resolve")
 356
 357 (defvar smerge-text-properties
 358   `(help-echo "merge conflict: mouse-3 shows a menu"
 359     ;; mouse-face highlight
 360     keymap (keymap (down-mouse-3 . smerge-popup-context-menu))))
 361
 362 (defun smerge-remove-props (beg end)
 363   (remove-overlays beg end 'smerge 'refine)
 364   (remove-overlays beg end 'smerge 'conflict)
 365   ;; Now that we use overlays rather than text-properties, this function
 366   ;; does not cause refontification any more.  It can be seen very clearly
 367   ;; in buffers where jit-lock-contextually is not t, in which case deleting
 368   ;; the "<<<<<<< foobar" leading line leaves the rest of the conflict
 369   ;; highlighted as if it were still a valid conflict.  Note that in many
 370   ;; important cases (such as the previous example) we're actually called
 371   ;; during font-locking so inhibit-modification-hooks is non-nil, so we
 372   ;; can't just modify the buffer and expect font-lock to be triggered as in:
 373   ;; (put-text-property beg end 'smerge-force-highlighting nil)
 374   (let ((modified (buffer-modified-p)))
 375     (remove-text-properties beg end '(fontified nil))
 376     (restore-buffer-modified-p modified)))
 377
 378 (defun smerge-popup-context-menu (event)
 379   "Pop up the Smerge mode context menu under mouse."
 380   (interactive "e")
 381   (if (and smerge-mode
 382            (save-excursion (posn-set-point (event-end event)) (smerge-check 1)))
 383       (progn
 384         (posn-set-point (event-end event))
 385         (smerge-match-conflict)
 386         (let ((i (smerge-get-current))
 387               o)
 388           (if (<= i 0)
 389               ;; Out of range
 390               (popup-menu smerge-mode-menu)
 391             ;; Install overlay.
 392             (setq o (make-overlay (match-beginning i) (match-end i)))
 393             (unwind-protect
 394                 (progn
 395                   (overlay-put o 'face 'highlight)
 396                   (sit-for 0)           ;Display the new highlighting.
 397                   (popup-menu smerge-context-menu))
 398               ;; Delete overlay.
 399               (delete-overlay o)))))
 400     ;; There's no conflict at point, the text-props are just obsolete.
 401     (save-excursion
 402       (let ((beg (re-search-backward smerge-end-re nil t))
 403             (end (re-search-forward smerge-begin-re nil t)))
 404         (smerge-remove-props (or beg (point-min)) (or end (point-max)))
 405         (push event unread-command-events)))))
 406
 407 (defun smerge-apply-resolution-patch (buf m0b m0e m3b m3e &optional m2b)
 408   "Replace the conflict with a bunch of subconflicts.
 409 BUF contains a plain diff between match-1 and match-3."
 410   (let ((line 1)
 411         (textbuf (current-buffer))
 412         (name1 (progn (goto-char m0b)
 413                       (buffer-substring (+ (point) 8) (line-end-position))))
 414         (name2 (when m2b (goto-char m2b) (forward-line -1)
 415                      (buffer-substring (+ (point) 8) (line-end-position))))
 416         (name3 (progn (goto-char m0e) (forward-line -1)
 417                       (buffer-substring (+ (point) 8) (line-end-position)))))
 418     (smerge-remove-props m0b m0e)
 419     (delete-region m3e m0e)
 420     (delete-region m0b m3b)
 421     (setq m3b m0b)
 422     (setq m3e (- m3e (- m3b m0b)))
 423     (goto-char m3b)
 424     (with-current-buffer buf
 425       (goto-char (point-min))
 426       (while (not (eobp))
 427         (if (not (looking-at "\\([0-9]+\\)\\(?:,\\([0-9]+\\)\\)?\\([acd]\\)\\([0-9]+\\)\\(?:,\\([0-9]+\\)\\)?$"))
 428             (error "Unexpected patch hunk header: %s"
 429                    (buffer-substring (point) (line-end-position)))
 430           (let* ((op (char-after (match-beginning 3)))
 431                  (startline (+ (string-to-number (match-string 1))
 432                                ;; No clue why this is the way it is, but line
 433                                ;; numbers seem to be off-by-one for `a' ops.
 434                                (if (eq op ?a) 1 0)))
 435                  (endline (if (eq op ?a) startline
 436                             (1+ (if (match-end 2)
 437                                     (string-to-number (match-string 2))
 438                                   startline))))
 439                  (lines (- endline startline))
 440                  (otherlines (cond
 441                               ((eq op ?d) nil)
 442                               ((null (match-end 5)) 1)
 443                               (t (- (string-to-number (match-string 5))
 444                                     (string-to-number (match-string 4)) -1))))
 445                  othertext)
 446             (forward-line 1)                             ;Skip header.
 447             (forward-line lines)                         ;Skip deleted text.
 448             (if (eq op ?c) (forward-line 1))             ;Skip separator.
 449             (setq othertext
 450                   (if (null otherlines) ""
 451                     (let ((pos (point)))
 452                       (dotimes (i otherlines) (delete-char 2) (forward-line 1))
 453                       (buffer-substring pos (point)))))
 454             (with-current-buffer textbuf
 455               (forward-line (- startline line))
 456               (insert "<<<<<<< " name1 "\n" othertext
 457                       (if name2 (concat "||||||| " name2 "\n") "")
 458                       "=======\n")
 459               (forward-line lines)
 460               (insert ">>>>>>> " name3 "\n")
 461               (setq line endline))))))))
 462
 463 (defun smerge-resolve (&optional safe)
 464   "Resolve the conflict at point intelligently.
 465 This relies on mode-specific knowledge and thus only works in
 466 some major modes.  Uses `smerge-resolve-function' to do the actual work."
 467   (interactive)
 468   (smerge-match-conflict)
 469   (smerge-remove-props (match-beginning 0) (match-end 0))
 470   (let ((md (match-data))
 471         (m0b (match-beginning 0))
 472         (m1b (match-beginning 1))
 473         (m2b (match-beginning 2))
 474         (m3b (match-beginning 3))
 475         (m0e (match-end 0))
 476         (m1e (match-end 1))
 477         (m2e (match-end 2))
 478         (m3e (match-end 3))
 479         (buf (generate-new-buffer " *smerge*"))
 480         m b o)
 481     (unwind-protect
 482         (progn
 483           (cond
 484            ;; Trivial diff3 -A non-conflicts.
 485            ((and (eq (match-end 1) (match-end 3))
 486                  (eq (match-beginning 1) (match-beginning 3)))
 487             (smerge-keep-n 3))
 488            ;; Mode-specific conflict resolution.
 489            ((condition-case nil
 490                 (atomic-change-group
 491                   (if safe
 492                       (funcall smerge-resolve-function safe)
 493                     (funcall smerge-resolve-function))
 494                   t)
 495               (error nil))
 496             ;; Nothing to do: the resolution function has done it already.
 497             nil)
 498            ;; Non-conflict.
 499            ((and (eq m1e m3e) (eq m1b m3b))
 500             (set-match-data md) (smerge-keep-n 3))
 501            ;; Refine a 2-way conflict using "diff -b".
 502            ;; In case of a 3-way conflict with an empty base
 503            ;; (i.e. 2 conflicting additions), we do the same, presuming
 504            ;; that the 2 additions should be somehow merged rather
 505            ;; than concatenated.
 506            ((let ((lines (count-lines m3b m3e)))
 507               (setq m (make-temp-file "smm"))
 508               (write-region m1b m1e m nil 'silent)
 509               (setq o (make-temp-file "smo"))
 510               (write-region m3b m3e o nil 'silent)
 511               (not (or (eq m1b m1e) (eq m3b m3e)
 512                        (and (not (zerop (call-process diff-command
 513                                                       nil buf nil "-b" o m)))
 514                             ;; TODO: We don't know how to do the refinement
 515                             ;; if there's a non-empty ancestor and m1 and m3
 516                             ;; aren't just plain equal.
 517                             m2b (not (eq m2b m2e)))
 518                        (with-current-buffer buf
 519                          (goto-char (point-min))
 520                          ;; Make sure there's some refinement.
 521                          (looking-at
 522                           (concat "1," (number-to-string lines) "c"))))))
 523             (smerge-apply-resolution-patch buf m0b m0e m3b m3e m2b))
 524            ;; "Mere whitespace changes" conflicts.
 525            ((when m2e
 526               (setq b (make-temp-file "smb"))
 527               (write-region m2b m2e b nil 'silent)
 528               (with-current-buffer buf (erase-buffer))
 529               ;; Only minor whitespace changes made locally.
 530               ;; BEWARE: pass "-c" 'cause the output is reused in the next test.
 531               (zerop (call-process diff-command nil buf nil "-bc" b m)))
 532             (set-match-data md)
 533             (smerge-keep-n 3))
 534            ;; Try "diff -b BASE MINE | patch OTHER".
 535            ((when (and (not safe) m2e b
 536                        ;; If the BASE is empty, this would just concatenate
 537                        ;; the two, which is rarely right.
 538                        (not (eq m2b m2e)))
 539               ;; BEWARE: we're using here the patch of the previous test.
 540               (with-current-buffer buf
 541                 (zerop (call-process-region
 542                         (point-min) (point-max) "patch" t nil nil
 543                         "-r" "/dev/null" "--no-backup-if-mismatch"
 544                         "-fl" o))))
 545             (save-restriction
 546               (narrow-to-region m0b m0e)
 547               (smerge-remove-props m0b m0e)
 548               (insert-file-contents o nil nil nil t)))
 549            ;; Try "diff -b BASE OTHER | patch MINE".
 550            ((when (and (not safe) m2e b
 551                        ;; If the BASE is empty, this would just concatenate
 552                        ;; the two, which is rarely right.
 553                        (not (eq m2b m2e)))
 554               (write-region m3b m3e o nil 'silent)
 555               (call-process diff-command nil buf nil "-bc" b o)
 556               (with-current-buffer buf
 557                 (zerop (call-process-region
 558                         (point-min) (point-max) "patch" t nil nil
 559                         "-r" "/dev/null" "--no-backup-if-mismatch"
 560                         "-fl" m))))
 561             (save-restriction
 562               (narrow-to-region m0b m0e)
 563               (smerge-remove-props m0b m0e)
 564               (insert-file-contents m nil nil nil t)))
 565            (t
 566             (error "Don't know how to resolve"))))
 567       (if (buffer-name buf) (kill-buffer buf))
 568       (if m (delete-file m))
 569       (if b (delete-file b))
 570       (if o (delete-file o))))
 571   (smerge-auto-leave))
 572
 573 (defun smerge-resolve-all ()
 574   "Perform automatic resolution on all conflicts."
 575   (interactive)
 576   (save-excursion
 577     (goto-char (point-min))
 578     (while (re-search-forward smerge-begin-re nil t)
 579       (condition-case nil
 580           (progn
 581             (smerge-match-conflict)
 582             (smerge-resolve 'safe))
 583         (error nil)))))
 584
 585 (defun smerge-batch-resolve ()
 586   ;; command-line-args-left is what is left of the command line.
 587   (if (not noninteractive)
 588       (error "`smerge-batch-resolve' is to be used only with -batch"))
 589   (while command-line-args-left
 590     (let ((file (pop command-line-args-left)))
 591       (if (string-match "\\.rej\\'" file)
 592           ;; .rej files should never contain diff3 markers, on the other hand,
 593           ;; in Arch, .rej files are sometimes used to indicate that the
 594           ;; main file has diff3 markers.  So you can pass **/*.rej and
 595           ;; it will DTRT.
 596           (setq file (substring file 0 (match-beginning 0))))
 597       (message "Resolving conflicts in %s..." file)
 598       (when (file-readable-p file)
 599         (with-current-buffer (find-file-noselect file)
 600           (smerge-resolve-all)
 601           (save-buffer)
 602           (kill-buffer (current-buffer)))))))
 603
 604 (defun smerge-keep-base ()
 605   "Revert to the base version."
 606   (interactive)
 607   (smerge-match-conflict)
 608   (smerge-ensure-match 2)
 609   (smerge-keep-n 2)
 610   (smerge-auto-leave))
 611
 612 (defun smerge-keep-other ()
 613   "Use \"other\" version."
 614   (interactive)
 615   (smerge-match-conflict)
 616   ;;(smerge-ensure-match 3)
 617   (smerge-keep-n 3)
 618   (smerge-auto-leave))
 619
 620 (defun smerge-keep-mine ()
 621   "Keep your version."
 622   (interactive)
 623   (smerge-match-conflict)
 624   ;;(smerge-ensure-match 1)
 625   (smerge-keep-n 1)
 626   (smerge-auto-leave))
 627
 628 (defun smerge-get-current ()
 629   (let ((i 3))
 630     (while (or (not (match-end i))
 631                (< (point) (match-beginning i))
 632                (>= (point) (match-end i)))
 633       (decf i))
 634     i))
 635
 636 (defun smerge-keep-current ()
 637   "Use the current (under the cursor) version."
 638   (interactive)
 639   (smerge-match-conflict)
 640   (let ((i (smerge-get-current)))
 641     (if (<= i 0) (error "Not inside a version")
 642       (smerge-keep-n i)
 643       (smerge-auto-leave))))
 644
 645 (defun smerge-kill-current ()
 646   "Remove the current (under the cursor) version."
 647   (interactive)
 648   (smerge-match-conflict)
 649   (let ((i (smerge-get-current)))
 650     (if (<= i 0) (error "Not inside a version")
 651       (let ((left nil))
 652         (dolist (n '(3 2 1))
 653           (if (and (match-end n) (/= (match-end n) (match-end i)))
 654               (push n left)))
 655         (if (and (cdr left)
 656                  (/= (match-end (car left)) (match-end (cadr left))))
 657             (ding)                      ;We don't know how to do that.
 658           (smerge-keep-n (car left))
 659           (smerge-auto-leave))))))
 660
 661 (defun smerge-diff-base-mine ()
 662   "Diff 'base' and 'mine' version in current conflict region."
 663   (interactive)
 664   (smerge-diff 2 1))
 665
 666 (defun smerge-diff-base-other ()
 667   "Diff 'base' and 'other' version in current conflict region."
 668   (interactive)
 669   (smerge-diff 2 3))
 670
 671 (defun smerge-diff-mine-other ()
 672   "Diff 'mine' and 'other' version in current conflict region."
 673   (interactive)
 674   (smerge-diff 1 3))
 675
 676 (defun smerge-match-conflict ()
 677   "Get info about the conflict.  Puts the info in the `match-data'.
 678 The submatches contain:
 679  0:  the whole conflict.
 680  1:  your code.
 681  2:  the base code.
 682  3:  other code.
 683 An error is raised if not inside a conflict."
 684   (save-excursion
 685     (condition-case nil
 686         (let* ((orig-point (point))
 687
 688                (_ (forward-line 1))
 689                (_ (re-search-backward smerge-begin-re))
 690
 691                (start (match-beginning 0))
 692                (mine-start (match-end 0))
 693                (filename (or (match-string 1) ""))
 694
 695                (_ (re-search-forward smerge-end-re))
 696                (_ (assert (< orig-point (match-end 0))))
 697
 698                (other-end (match-beginning 0))
 699                (end (match-end 0))
 700
 701                (_ (re-search-backward smerge-other-re start))
 702
 703                (mine-end (match-beginning 0))
 704                (other-start (match-end 0))
 705
 706                base-start base-end)
 707
 708           ;; handle the various conflict styles
 709           (cond
 710            ((save-excursion
 711               (goto-char mine-start)
 712               (re-search-forward smerge-begin-re end t))
 713             ;; There's a nested conflict and we're after the the beginning
 714             ;; of the outer one but before the beginning of the inner one.
 715             ;; Of course, maybe this is not a nested conflict but in that
 716             ;; case it can only be something nastier that we don't know how
 717             ;; to handle, so may as well arbitrarily decide to treat it as
 718             ;; a nested conflict.  --Stef
 719             (error "There is a nested conflict"))
 720
 721            ((re-search-backward smerge-base-re start t)
 722             ;; a 3-parts conflict
 723             (set (make-local-variable 'smerge-conflict-style) 'diff3-A)
 724             (setq base-end mine-end)
 725             (setq mine-end (match-beginning 0))
 726             (setq base-start (match-end 0)))
 727
 728            ((string= filename (file-name-nondirectory
 729                                (or buffer-file-name "")))
 730             ;; a 2-parts conflict
 731             (set (make-local-variable 'smerge-conflict-style) 'diff3-E))
 732
 733            ((and (not base-start)
 734                  (or (eq smerge-conflict-style 'diff3-A)
 735                      (equal filename "ANCESTOR")
 736                      (string-match "\\`[.0-9]+\\'" filename)))
 737             ;; a same-diff conflict
 738             (setq base-start mine-start)
 739             (setq base-end   mine-end)
 740             (setq mine-start other-start)
 741             (setq mine-end   other-end)))
 742
 743           (store-match-data (list start end
 744                                   mine-start mine-end
 745                                   base-start base-end
 746                                   other-start other-end
 747                                   (when base-start (1- base-start)) base-start
 748                                   (1- other-start) other-start))
 749           t)
 750       (search-failed (error "Point not in conflict region")))))
 751
 752 (add-to-list 'debug-ignored-errors "Point not in conflict region")
 753
 754 (defun smerge-conflict-overlay (pos)
 755   "Return the conflict overlay at POS if any."
 756   (let ((ols (overlays-at pos))
 757         conflict)
 758     (dolist (ol ols)
 759       (if (and (eq (overlay-get ol 'smerge) 'conflict)
 760                (> (overlay-end ol) pos))
 761           (setq conflict ol)))
 762     conflict))
 763
 764 (defun smerge-find-conflict (&optional limit)
 765   "Find and match a conflict region.  Intended as a font-lock MATCHER.
 766 The submatches are the same as in `smerge-match-conflict'.
 767 Returns non-nil if a match is found between point and LIMIT.
 768 Point is moved to the end of the conflict."
 769   (let ((found nil)
 770         (pos (point))
 771         conflict)
 772     ;; First check to see if point is already inside a conflict, using
 773     ;; the conflict overlays.
 774     (while (and (not found) (setq conflict (smerge-conflict-overlay pos)))
 775       ;; Check the overlay's validity and kill it if it's out of date.
 776       (condition-case nil
 777           (progn
 778             (goto-char (overlay-start conflict))
 779             (smerge-match-conflict)
 780             (goto-char (match-end 0))
 781             (if (<= (point) pos)
 782                 (error "Matching backward!")
 783               (setq found t)))
 784         (error (smerge-remove-props
 785                 (overlay-start conflict) (overlay-end conflict))
 786                (goto-char pos))))
 787     ;; If we're not already inside a conflict, look for the next conflict
 788     ;; and add/update its overlay.
 789     (while (and (not found) (re-search-forward smerge-begin-re limit t))
 790       (condition-case nil
 791           (progn
 792             (smerge-match-conflict)
 793             (goto-char (match-end 0))
 794             (let ((conflict (smerge-conflict-overlay (1- (point)))))
 795               (if conflict
 796                   ;; Update its location, just in case it got messed up.
 797                   (move-overlay conflict (match-beginning 0) (match-end 0))
 798                 (setq conflict (make-overlay (match-beginning 0) (match-end 0)
 799                                              nil 'front-advance nil))
 800                 (overlay-put conflict 'evaporate t)
 801                 (overlay-put conflict 'smerge 'conflict)
 802                 (let ((props smerge-text-properties))
 803                   (while props
 804                     (overlay-put conflict (pop props) (pop props))))))
 805             (setq found t))
 806         (error nil)))
 807     found))
 808
 809 ;;; Refined change highlighting
 810
 811 (defvar smerge-refine-forward-function 'smerge-refine-forward
 812   "Function used to determine an \"atomic\" element.
 813 You can set it to `forward-char' to get char-level granularity.
 814 Its behavior has mainly two restrictions:
 815 - if this function encounters a newline, it's important that it stops right
 816   after the newline.
 817   This only matters if `smerge-refine-ignore-whitespace' is nil.
 818 - it needs to be unaffected by changes performed by the `preproc' argument
 819   to `smerge-refine-subst'.
 820   This only matters if `smerge-refine-weight-hack' is nil.")
 821
 822 (defvar smerge-refine-ignore-whitespace t
 823   "If non-nil,Indicate that smerge-refine should try to ignore change in whitespace.")
 824
 825 (defvar smerge-refine-weight-hack t
 826   "If non-nil, pass to diff as many lines as there are chars in the region.
 827 I.e. each atomic element (e.g. word) will be copied as many times (on different
 828 lines) as it has chars.  This has 2 advantages:
 829 - if `diff' tries to minimize the number *lines* (rather than chars)
 830   added/removed, this adjust the weights so that adding/removing long
 831   symbols is considered correspondingly more costly.
 832 - `smerge-refine-forward-function' only needs to be called when chopping up
 833   the regions, and `forward-char' can be used afterwards.
 834 It has the following disadvantages:
 835 - cannot use `diff -w' because the weighting causes added spaces in a line
 836   to be represented as added copies of some line, so `diff -w' can't do the
 837   right thing any more.
 838 - may in degenerate cases take a 1KB input region and turn it into a 1MB
 839   file to pass to diff.")
 840
 841 (defun smerge-refine-forward (n)
 842   (let ((case-fold-search nil)
 843         (re "[[:upper:]]?[[:lower:]]+\\|[[:upper:]]+\\|[[:digit:]]+\\|.\\|\n"))
 844     (when (and smerge-refine-ignore-whitespace
 845                ;; smerge-refine-weight-hack causes additional spaces to
 846                ;; appear as additional lines as well, so even if diff ignore
 847                ;; whitespace changes, it'll report added/removed lines :-(
 848                (not smerge-refine-weight-hack))
 849       (setq re (concat "[ \t]*\\(?:" re "\\)")))
 850     (dotimes (i n)
 851       (unless (looking-at re) (error "Smerge refine internal error"))
 852       (goto-char (match-end 0)))))
 853
 854 (defun smerge-refine-chopup-region (beg end file &optional preproc)
 855   "Chopup the region into small elements, one per line.
 856 Save the result into FILE.
 857 If non-nil, PREPROC is called with no argument in a buffer that contains
 858 a copy of the text, just before chopping it up.  It can be used to replace
 859 chars to try and eliminate some spurious differences."
 860   ;; We used to chop up char-by-char rather than word-by-word like ediff
 861   ;; does.  It had the benefit of simplicity and very fine results, but it
 862   ;; often suffered from problem that diff would find correlations where
 863   ;; there aren't any, so the resulting "change" didn't make much sense.
 864   ;; You can still get this behavior by setting
 865   ;; `smerge-refine-forward-function' to `forward-char'.
 866   (let ((buf (current-buffer)))
 867     (with-temp-buffer
 868       (insert-buffer-substring buf beg end)
 869       (when preproc (goto-char (point-min)) (funcall preproc))
 870       (when smerge-refine-ignore-whitespace
 871         ;; It doesn't make much of a difference for diff-fine-highlight
 872         ;; because we still have the _/+/</>/! prefix anyway.  Can still be
 873         ;; useful in other circumstances.
 874         (subst-char-in-region (point-min) (point-max) ?\n ?\s))
 875       (goto-char (point-min))
 876       (while (not (eobp))
 877         (funcall smerge-refine-forward-function 1)
 878         (let ((s (if (prog2 (forward-char -1) (bolp) (forward-char 1))
 879                      nil
 880                    (buffer-substring (line-beginning-position) (point)))))
 881           ;; We add \n after each char except after \n, so we get
 882           ;; one line per text char, where each line contains
 883           ;; just one char, except for \n chars which are
 884           ;; represented by the empty line.
 885           (unless (eq (char-before) ?\n) (insert ?\n))
 886           ;; HACK ALERT!!
 887           (if smerge-refine-weight-hack
 888               (dotimes (i (1- (length s))) (insert s "\n")))))
 889       (unless (bolp) (error "Smerge refine internal error"))
 890       (let ((coding-system-for-write 'emacs-mule))
 891         (write-region (point-min) (point-max) file nil 'nomessage)))))
 892
 893 (defun smerge-refine-highlight-change (buf beg match-num1 match-num2 props)
 894   (with-current-buffer buf
 895     (goto-char beg)
 896     (let* ((startline (- (string-to-number match-num1) 1))
 897            (beg (progn (funcall (if smerge-refine-weight-hack
 898                                     'forward-char
 899                                   smerge-refine-forward-function)
 900                                 startline)
 901                        (point)))
 902            (end (progn (funcall (if smerge-refine-weight-hack
 903                                     'forward-char
 904                                   smerge-refine-forward-function)
 905                           (if match-num2
 906                               (- (string-to-number match-num2)
 907                                  startline)
 908                             1))
 909                        (point))))
 910       (when smerge-refine-ignore-whitespace
 911         (skip-chars-backward " \t\n" beg) (setq end (point))
 912         (goto-char beg)
 913         (skip-chars-forward " \t\n" end)  (setq beg (point)))
 914       (when (> end beg)
 915         (let ((ol (make-overlay
 916                    beg end nil
 917                    ;; Make them tend to shrink rather than spread when editing.
 918                    'front-advance nil)))
 919           (overlay-put ol 'evaporate t)
 920           (dolist (x props) (overlay-put ol (car x) (cdr x)))
 921           ol)))))
 922
 923 (defun smerge-refine-subst (beg1 end1 beg2 end2 props &optional preproc)
 924   "Show fine differences in the two regions BEG1..END1 and BEG2..END2.
 925 PROPS is an alist of properties to put (via overlays) on the changes.
 926 If non-nil, PREPROC is called with no argument in a buffer that contains
 927 a copy of a region, just before preparing it to for `diff'.  It can be used to
 928 replace chars to try and eliminate some spurious differences."
 929   (let* ((buf (current-buffer))
 930          (pos (point))
 931          (file1 (make-temp-file "diff1"))
 932          (file2 (make-temp-file "diff2")))
 933     ;; Chop up regions into smaller elements and save into files.
 934     (smerge-refine-chopup-region beg1 end1 file1 preproc)
 935     (smerge-refine-chopup-region beg2 end2 file2 preproc)
 936
 937     ;; Call diff on those files.
 938     (unwind-protect
 939         (with-temp-buffer
 940           (let ((coding-system-for-read 'emacs-mule))
 941             (call-process diff-command nil t nil
 942                           (if (and smerge-refine-ignore-whitespace
 943                                    (not smerge-refine-weight-hack))
 944                               ;; Pass -a so diff treats it as a text file even
 945                               ;; if it contains \0 and such.
 946                               ;; Pass -d so as to get the smallest change, but
 947                               ;; also and more importantly because otherwise it
 948                               ;; may happen that diff doesn't behave like
 949                               ;; smerge-refine-weight-hack expects it to.
 950                               ;; See http://thread.gmane.org/gmane.emacs.devel/82685.
 951                               "-awd" "-ad")
 952                           file1 file2))
 953           ;; Process diff's output.
 954           (goto-char (point-min))
 955           (let ((last1 nil)
 956                 (last2 nil))
 957             (while (not (eobp))
 958               (if (not (looking-at "\\([0-9]+\\)\\(?:,\\([0-9]+\\)\\)?\\([acd]\\)\\([0-9]+\\)\\(?:,\\([0-9]+\\)\\)?$"))
 959                   (error "Unexpected patch hunk header: %s"
 960                          (buffer-substring (point) (line-end-position))))
 961               (let ((op (char-after (match-beginning 3)))
 962                     (m1 (match-string 1))
 963                     (m2 (match-string 2))
 964                     (m4 (match-string 4))
 965                     (m5 (match-string 5)))
 966                 (when (memq op '(?d ?c))
 967                   (setq last1
 968                         (smerge-refine-highlight-change buf beg1 m1 m2 props)))
 969                 (when (memq op '(?a ?c))
 970                   (setq last2
 971                         (smerge-refine-highlight-change buf beg2 m4 m5 props))))
 972               (forward-line 1)                            ;Skip hunk header.
 973               (and (re-search-forward "^[0-9]" nil 'move) ;Skip hunk body.
 974                    (goto-char (match-beginning 0))))
 975             ;; (assert (or (null last1) (< (overlay-start last1) end1)))
 976             ;; (assert (or (null last2) (< (overlay-start last2) end2)))
 977             (if smerge-refine-weight-hack
 978                 (progn
 979                   ;; (assert (or (null last1) (<= (overlay-end last1) end1)))
 980                   ;; (assert (or (null last2) (<= (overlay-end last2) end2)))
 981                   )
 982               ;; smerge-refine-forward-function when calling in chopup may
 983               ;; have stopped because it bumped into EOB whereas in
 984               ;; smerge-refine-weight-hack it may go a bit further.
 985               (if (and last1 (> (overlay-end last1) end1))
 986                   (move-overlay last1 (overlay-start last1) end1))
 987               (if (and last2 (> (overlay-end last2) end2))
 988                   (move-overlay last2 (overlay-start last2) end2))
 989               )))
 990       (goto-char pos)
 991       (delete-file file1)
 992       (delete-file file2))))
 993
 994 (defun smerge-refine (&optional part)
 995   "Highlight the words of the conflict that are different.
 996 For 3-way conflicts, highlights only 2 of the 3 parts.
 997 A numeric argument PART can be used to specify which 2 parts;
 998 repeating the command will highlight other 2 parts."
 999   (interactive
1000    (if (integerp current-prefix-arg) (list current-prefix-arg)
1001      (smerge-match-conflict)
1002      (let* ((prop (get-text-property (match-beginning 0) 'smerge-refine-part))
1003             (part (if (and (consp prop)
1004                            (eq (buffer-chars-modified-tick) (car prop)))
1005                       (cdr prop))))
1006        ;; If already highlighted, cycle.
1007        (list (if (integerp part) (1+ (mod part 3)))))))
1008
1009   (if (and (integerp part) (or (< part 1) (> part 3)))
1010       (error "No conflict part nb %s" part))
1011   (smerge-match-conflict)
1012   (remove-overlays (match-beginning 0) (match-end 0) 'smerge 'refine)
1013   ;; Ignore `part' if not applicable, and default it if not provided.
1014   (setq part (cond ((null (match-end 2)) 2)
1015                    ((eq (match-end 1) (match-end 3)) 1)
1016                    ((integerp part) part)
1017                    (t 2)))
1018   (let ((n1 (if (eq part 1) 2 1))
1019         (n2 (if (eq part 3) 2 3)))
1020     (smerge-ensure-match n1)
1021     (smerge-ensure-match n2)
1022     (put-text-property (match-beginning 0) (1+ (match-beginning 0))
1023                        'smerge-refine-part
1024                        (cons (buffer-chars-modified-tick) part))
1025     (smerge-refine-subst (match-beginning n1) (match-end n1)
1026                          (match-beginning n2)  (match-end n2)
1027                          '((smerge . refine)
1028                            (face . smerge-refined-change)))))
1029
1030 (defun smerge-diff (n1 n2)
1031   (smerge-match-conflict)
1032   (smerge-ensure-match n1)
1033   (smerge-ensure-match n2)
1034   (let ((name1 (aref smerge-match-names n1))
1035         (name2 (aref smerge-match-names n2))
1036         ;; Read them before the match-data gets clobbered.
1037         (beg1 (match-beginning n1))
1038         (end1 (match-end n1))
1039         (beg2 (match-beginning n2))
1040         (end2 (match-end n2))
1041         (file1 (make-temp-file "smerge1"))
1042         (file2 (make-temp-file "smerge2"))
1043         (dir default-directory)
1044         (file (if buffer-file-name (file-relative-name buffer-file-name)))
1045         ;; We would want to use `emacs-mule-unix' for read&write, but we
1046         ;; bump into problems with the coding-system used by diff to write
1047         ;; the file names and the time stamps in the header.
1048         ;; `buffer-file-coding-system' is not always correct either, but if
1049         ;; the OS/user uses only one coding-system, then it works.
1050         (coding-system-for-read buffer-file-coding-system))
1051     (write-region beg1 end1 file1 nil 'nomessage)
1052     (write-region beg2 end2 file2 nil 'nomessage)
1053     (unwind-protect
1054         (with-current-buffer (get-buffer-create smerge-diff-buffer-name)
1055           (setq default-directory dir)
1056           (let ((inhibit-read-only t))
1057             (erase-buffer)
1058             (let ((status
1059                    (apply 'call-process diff-command nil t nil
1060                           (append smerge-diff-switches
1061                                   (list "-L" (concat name1 "/" file)
1062                                         "-L" (concat name2 "/" file)
1063                                         file1 file2)))))
1064               (if (eq status 0) (insert "No differences found.\n"))))
1065           (goto-char (point-min))
1066           (diff-mode)
1067           (display-buffer (current-buffer) t))
1068       (delete-file file1)
1069       (delete-file file2))))
1070
1071 ;; compiler pacifiers
1072 (defvar smerge-ediff-windows)
1073 (defvar smerge-ediff-buf)
1074 (defvar ediff-buffer-A)
1075 (defvar ediff-buffer-B)
1076 (defvar ediff-buffer-C)
1077 (defvar ediff-ancestor-buffer)
1078 (defvar ediff-quit-hook)
1079 (declare-function ediff-cleanup-mess "ediff-util" nil)
1080
1081 ;;;###autoload
1082 (defun smerge-ediff (&optional name-mine name-other name-base)
1083   "Invoke ediff to resolve the conflicts.
1084 NAME-MINE, NAME-OTHER, and NAME-BASE, if non-nil, are used for the
1085 buffer names."
1086   (interactive)
1087   (let* ((buf (current-buffer))
1088          (mode major-mode)
1089          ;;(ediff-default-variant 'default-B)
1090          (config (current-window-configuration))
1091          (filename (file-name-nondirectory buffer-file-name))
1092          (mine (generate-new-buffer
1093                 (or name-mine (concat "*" filename " MINE*"))))
1094          (other (generate-new-buffer
1095                  (or name-other (concat "*" filename " OTHER*"))))
1096          base)
1097     (with-current-buffer mine
1098       (buffer-disable-undo)
1099       (insert-buffer-substring buf)
1100       (goto-char (point-min))
1101       (while (smerge-find-conflict)
1102         (when (match-beginning 2) (setq base t))
1103         (smerge-keep-n 1))
1104       (buffer-enable-undo)
1105       (set-buffer-modified-p nil)
1106       (funcall mode))
1107
1108     (with-current-buffer other
1109       (buffer-disable-undo)
1110       (insert-buffer-substring buf)
1111       (goto-char (point-min))
1112       (while (smerge-find-conflict)
1113         (smerge-keep-n 3))
1114       (buffer-enable-undo)
1115       (set-buffer-modified-p nil)
1116       (funcall mode))
1117
1118     (when base
1119       (setq base (generate-new-buffer
1120                   (or name-base (concat "*" filename " BASE*"))))
1121       (with-current-buffer base
1122         (buffer-disable-undo)
1123         (insert-buffer-substring buf)
1124         (goto-char (point-min))
1125         (while (smerge-find-conflict)
1126           (if (match-end 2)
1127               (smerge-keep-n 2)
1128             (delete-region (match-beginning 0) (match-end 0))))
1129         (buffer-enable-undo)
1130         (set-buffer-modified-p nil)
1131         (funcall mode)))
1132
1133     ;; the rest of the code is inspired from vc.el
1134     ;; Fire up ediff.
1135     (set-buffer
1136      (if base
1137          (ediff-merge-buffers-with-ancestor mine other base)
1138           ;; nil 'ediff-merge-revisions-with-ancestor buffer-file-name)
1139        (ediff-merge-buffers mine other)))
1140         ;; nil 'ediff-merge-revisions buffer-file-name)))
1141
1142     ;; Ediff is now set up, and we are in the control buffer.
1143     ;; Do a few further adjustments and take precautions for exit.
1144     (set (make-local-variable 'smerge-ediff-windows) config)
1145     (set (make-local-variable 'smerge-ediff-buf) buf)
1146     (set (make-local-variable 'ediff-quit-hook)
1147          (lambda ()
1148            (let ((buffer-A ediff-buffer-A)
1149                  (buffer-B ediff-buffer-B)
1150                  (buffer-C ediff-buffer-C)
1151                  (buffer-Ancestor ediff-ancestor-buffer)
1152                  (buf smerge-ediff-buf)
1153                  (windows smerge-ediff-windows))
1154              (ediff-cleanup-mess)
1155              (with-current-buffer buf
1156                (erase-buffer)
1157                (insert-buffer-substring buffer-C)
1158                (kill-buffer buffer-A)
1159                (kill-buffer buffer-B)
1160                (kill-buffer buffer-C)
1161                (when (bufferp buffer-Ancestor) (kill-buffer buffer-Ancestor))
1162                (set-window-configuration windows)
1163                (message "Conflict resolution finished; you may save the buffer")))))
1164     (message "Please resolve conflicts now; exit ediff when done")))
1165
1166 (defun smerge-makeup-conflict (pt1 pt2 pt3 &optional pt4)
1167   "Insert diff3 markers to make a new conflict.
1168 Uses point and mark for 2 of the relevant positions and previous marks
1169 for the other ones.
1170 By default, makes up a 2-way conflict,
1171 with a \\[universal-argument] prefix, makes up a 3-way conflict."
1172   (interactive
1173    (list (point)
1174          (mark)
1175          (progn (pop-mark) (mark))
1176          (when current-prefix-arg (pop-mark) (mark))))
1177   ;; Start from the end so as to avoid problems with pos-changes.
1178   (destructuring-bind (pt1 pt2 pt3 &optional pt4)
1179       (sort (list* pt1 pt2 pt3 (if pt4 (list pt4))) '>=)
1180     (goto-char pt1) (beginning-of-line)
1181     (insert ">>>>>>> OTHER\n")
1182     (goto-char pt2) (beginning-of-line)
1183     (insert "=======\n")
1184     (goto-char pt3) (beginning-of-line)
1185     (when pt4
1186       (insert "||||||| BASE\n")
1187       (goto-char pt4) (beginning-of-line))
1188     (insert "<<<<<<< MINE\n"))
1189   (if smerge-mode nil (smerge-mode 1))
1190   (smerge-refine))
1191
1192
1193 (defconst smerge-parsep-re
1194   (concat smerge-begin-re "\\|" smerge-end-re "\\|"
1195           smerge-base-re "\\|" smerge-other-re "\\|"))
1196
1197 ;;;###autoload
1198 (define-minor-mode smerge-mode
1199   "Minor mode to simplify editing output from the diff3 program.
1200 \\{smerge-mode-map}"
1201   :group 'smerge :lighter " SMerge"
1202   (when (and (boundp 'font-lock-mode) font-lock-mode)
1203     (save-excursion
1204       (if smerge-mode
1205           (font-lock-add-keywords nil smerge-font-lock-keywords 'append)
1206         (font-lock-remove-keywords nil smerge-font-lock-keywords))
1207       (goto-char (point-min))
1208       (while (smerge-find-conflict)
1209         (save-excursion
1210           (font-lock-fontify-region (match-beginning 0) (match-end 0) nil)))))
1211   (if (string-match (regexp-quote smerge-parsep-re) paragraph-separate)
1212       (unless smerge-mode
1213         (set (make-local-variable 'paragraph-separate)
1214              (replace-match "" t t paragraph-separate)))
1215     (when smerge-mode
1216         (set (make-local-variable 'paragraph-separate)
1217              (concat smerge-parsep-re paragraph-separate))))
1218   (unless smerge-mode
1219     (smerge-remove-props (point-min) (point-max))))
1220
1221 ;;;###autoload
1222 (defun smerge-start-session ()
1223   "Turn on `smerge-mode' and move point to first conflict marker.
1224 If no conflict maker is found, turn off `smerge-mode'."
1225   (smerge-mode 1)
1226   (condition-case nil
1227       (unless (looking-at smerge-begin-re)
1228         (smerge-next))
1229     (error (smerge-auto-leave))))
1230
1231 (provide 'smerge-mode)
1232
1233 ;; arch-tag: 605c8d1e-e43d-4943-a6f3-1bcc4333e690
1234 ;;; smerge-mode.el ends here