lisp/smerge-mode.el

   1 ;;; smerge-mode.el --- Minor mode to resolve diff3 conflicts
   2
   3 ;; Copyright (C) 1999, 2000, 2001  Free Software Foundation, Inc.
   4
   5 ;; Author: Stefan Monnier <monnier@cs.yale.edu>
   6 ;; Keywords: merge diff3 cvs conflict
   7 ;; Revision: $Id: smerge-mode.el,v 1.16 2002/08/15 00:24:56 monnier Exp $
   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 2, 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., 59 Temple Place - Suite 330,
  24 ;; Boston, MA 02111-1307, 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 (defgroup smerge ()
  53   "Minor mode to resolve diff3 conflicts."
  54   :group 'tools
  55   :prefix "smerge-")
  56
  57 (defcustom smerge-diff-buffer-name "*vc-diff*"
  58   "Buffer name to use for displaying diffs."
  59   :group 'smerge
  60   :type '(choice
  61           (const "*vc-diff*")
  62           (const "*cvs-diff*")
  63           (const "*smerge-diff*")
  64           string))
  65
  66 (defcustom smerge-diff-switches
  67   (append '("-d" "-b")
  68           (if (listp diff-switches) diff-switches (list diff-switches)))
  69   "*A list of strings specifying switches to be be passed to diff.
  70 Used in `smerge-diff-base-mine' and related functions."
  71   :group 'smerge
  72   :type '(repeat string))
  73
  74 (defcustom smerge-auto-leave t
  75   "*Non-nil means to leave `smerge-mode' when the last conflict is resolved."
  76   :group 'smerge
  77   :type 'boolean)
  78
  79 (defface smerge-mine-face
  80   '((((background light))
  81      (:foreground "blue"))
  82     (((background dark))
  83      (:foreground "cyan")))
  84   "Face for your code."
  85   :group 'smerge)
  86 (defvar smerge-mine-face 'smerge-mine-face)
  87
  88 (defface smerge-other-face
  89   '((((background light))
  90      (:foreground "darkgreen"))
  91     (((background dark))
  92      (:foreground "lightgreen")))
  93   "Face for the other code."
  94   :group 'smerge)
  95 (defvar smerge-other-face 'smerge-other-face)
  96
  97 (defface smerge-base-face
  98   '((((background light))
  99      (:foreground "red"))
 100     (((background dark))
 101      (:foreground "orange")))
 102   "Face for the base code."
 103   :group 'smerge)
 104 (defvar smerge-base-face 'smerge-base-face)
 105
 106 (defface smerge-markers-face
 107   '((((background light))
 108      (:background "grey85"))
 109     (((background dark))
 110      (:background "grey30")))
 111   "Face for the conflict markers."
 112   :group 'smerge)
 113 (defvar smerge-markers-face 'smerge-markers-face)
 114
 115 (easy-mmode-defmap smerge-basic-map
 116   `(("n" . smerge-next)
 117     ("p" . smerge-prev)
 118     ("a" . smerge-keep-all)
 119     ("b" . smerge-keep-base)
 120     ("o" . smerge-keep-other)
 121     ("m" . smerge-keep-mine)
 122     ("E" . smerge-ediff)
 123     ("\C-m" . smerge-keep-current)
 124     ("=" . ,(make-sparse-keymap "Diff"))
 125     ("=<" "base-mine" . smerge-diff-base-mine)
 126     ("=>" "base-other" . smerge-diff-base-other)
 127     ("==" "mine-other" . smerge-diff-mine-other))
 128   "The base keymap for `smerge-mode'.")
 129
 130 (defcustom smerge-command-prefix "\C-c^"
 131   "Prefix for `smerge-mode' commands."
 132   :group 'smerge
 133   :type '(choice (string "\e") (string "\C-c^") (string "") string))
 134
 135 (easy-mmode-defmap smerge-mode-map
 136   `((,smerge-command-prefix . ,smerge-basic-map))
 137   "Keymap for `smerge-mode'.")
 138
 139 (easy-menu-define smerge-mode-menu smerge-mode-map
 140   "Menu for `smerge-mode'."
 141   '("SMerge"
 142     ["Next" smerge-next :help "Go to next conflict"]
 143     ["Previous" smerge-prev :help "Go to previous conflict"]
 144     ["Keep All" smerge-keep-all :help "Keep all three versions"]
 145     ["Revert to Base" smerge-keep-base :help "Revert to base version"]
 146     ["Keep Other" smerge-keep-other :help "Keep `other' version"]
 147     ["Keep Yours" smerge-keep-mine :help "Keep your version"]
 148     ["Keep Current" smerge-keep-current :help "Use current (at point) version"]
 149     "--"
 150     ["Diff Base/Mine" smerge-diff-base-mine
 151      :help "Diff `base' and `mine' for current conflict"]
 152     ["Diff Base/Other" smerge-diff-base-other
 153      :help "Diff `base' and `other' for current conflict"]
 154     ["Diff Mine/Other" smerge-diff-mine-other
 155      :help "Diff `mine' and `other' for current conflict"]
 156     "--"
 157     ["Invoke Ediff" smerge-ediff
 158      :help "Use Ediff to resolve the conflicts"]
 159     ))
 160
 161 (defconst smerge-font-lock-keywords
 162   '((smerge-find-conflict
 163      (1 smerge-mine-face prepend t)
 164      (2 smerge-base-face prepend t)
 165      (3 smerge-other-face prepend t)
 166      ;; FIXME: `keep' doesn't work right with syntactic fontification.
 167      (0 smerge-markers-face keep)
 168      (4 nil t t)
 169      (5 nil t t)))
 170   "Font lock patterns for `smerge-mode'.")
 171
 172 (defconst smerge-begin-re "^<<<<<<< \\(.*\\)\n")
 173 (defconst smerge-end-re "^>>>>>>> .*\n")
 174 (defconst smerge-base-re "^||||||| .*\n")
 175 (defconst smerge-other-re "^=======\n")
 176
 177 (defvar smerge-conflict-style nil
 178   "Keep track of which style of conflict is in use.
 179 Can be nil if the style is undecided, or else:
 180 - `diff3-E'
 181 - `diff3-A'")
 182
 183 ;; Compiler pacifiers
 184 (defvar font-lock-mode)
 185 (defvar font-lock-keywords)
 186
 187 ;;;;
 188 ;;;; Actual code
 189 ;;;;
 190
 191 ;; Define smerge-next and smerge-prev
 192 (easy-mmode-define-navigation smerge smerge-begin-re "conflict")
 193
 194 (defconst smerge-match-names ["conflict" "mine" "base" "other"])
 195
 196 (defun smerge-ensure-match (n)
 197   (unless (match-end n)
 198     (error (format "No `%s'" (aref smerge-match-names n)))))
 199
 200 (defun smerge-auto-leave ()
 201   (when (and smerge-auto-leave
 202              (save-excursion (goto-char (point-min))
 203                              (not (re-search-forward smerge-begin-re nil t))))
 204     (smerge-mode -1)))
 205
 206
 207 (defun smerge-keep-all ()
 208   "Keep all three versions.
 209 Convenient for the kind of conflicts that can arise in ChangeLog files."
 210   (interactive)
 211   (smerge-match-conflict)
 212   (replace-match (concat (or (match-string 1) "")
 213                          (or (match-string 2) "")
 214                          (or (match-string 3) ""))
 215                  t t)
 216   (smerge-auto-leave))
 217
 218 (defun smerge-combine-with-next ()
 219   "Combine the current conflict with the next one."
 220   (interactive)
 221   (smerge-match-conflict)
 222   (let ((ends nil))
 223     (dolist (i '(3 2 1 0))
 224       (push (if (match-end i) (copy-marker (match-end i) t)) ends))
 225     (setq ends (apply 'vector ends))
 226     (goto-char (aref ends 0))
 227     (if (not (re-search-forward smerge-begin-re nil t))
 228         (error "No next conflict")
 229       (smerge-match-conflict)
 230       (let ((match-data (mapcar (lambda (m) (if m (copy-marker m)))
 231                                 (match-data))))
 232         ;; First copy the in-between text in each alternative.
 233         (dolist (i '(1 2 3))
 234           (when (aref ends i)
 235             (goto-char (aref ends i))
 236             (insert-buffer-substring (current-buffer)
 237                                      (aref ends 0) (car match-data))))
 238         (delete-region (aref ends 0) (car match-data))
 239         ;; Then move the second conflict's alternatives into the first.
 240         (dolist (i '(1 2 3))
 241           (set-match-data match-data)
 242           (when (and (aref ends i) (match-end i))
 243             (goto-char (aref ends i))
 244             (insert-buffer-substring (current-buffer)
 245                                      (match-beginning i) (match-end i))))
 246         (delete-region (car match-data) (cadr match-data))
 247         ;; Free the markers.
 248         (dolist (m match-data) (if m (move-marker m nil)))
 249         (mapc (lambda (m) (if m (move-marker m nil))) ends)))))
 250
 251 (defun smerge-keep-base ()
 252   "Revert to the base version."
 253   (interactive)
 254   (smerge-match-conflict)
 255   (smerge-ensure-match 2)
 256   (replace-match (match-string 2) t t)
 257   (smerge-auto-leave))
 258
 259 (defun smerge-keep-other ()
 260   "Use \"other\" version."
 261   (interactive)
 262   (smerge-match-conflict)
 263   ;;(smerge-ensure-match 3)
 264   (replace-match (match-string 3) t t)
 265   (smerge-auto-leave))
 266
 267 (defun smerge-keep-mine ()
 268   "Keep your version."
 269   (interactive)
 270   (smerge-match-conflict)
 271   ;;(smerge-ensure-match 1)
 272   (replace-match (match-string 1) t t)
 273   (smerge-auto-leave))
 274
 275 (defun smerge-keep-current ()
 276   "Use the current (under the cursor) version."
 277   (interactive)
 278   (smerge-match-conflict)
 279   (let ((i 3))
 280     (while (or (not (match-end i))
 281                (< (point) (match-beginning i))
 282                (>= (point) (match-end i)))
 283       (decf i))
 284     (if (<= i 0) (error "Not inside a version")
 285       (replace-match (match-string i) t t)
 286       (smerge-auto-leave))))
 287
 288 (defun smerge-diff-base-mine ()
 289   "Diff 'base' and 'mine' version in current conflict region."
 290   (interactive)
 291   (smerge-diff 2 1))
 292
 293 (defun smerge-diff-base-other ()
 294   "Diff 'base' and 'other' version in current conflict region."
 295   (interactive)
 296   (smerge-diff 2 3))
 297
 298 (defun smerge-diff-mine-other ()
 299   "Diff 'mine' and 'other' version in current conflict region."
 300   (interactive)
 301   (smerge-diff 1 3))
 302
 303 (defun smerge-match-conflict ()
 304   "Get info about the conflict.  Puts the info in the `match-data'.
 305 The submatches contain:
 306  0:  the whole conflict.
 307  1:  your code.
 308  2:  the base code.
 309  3:  other code.
 310 An error is raised if not inside a conflict."
 311   (save-excursion
 312     (condition-case nil
 313         (let* ((orig-point (point))
 314
 315                (_ (forward-line 1))
 316                (_ (re-search-backward smerge-begin-re))
 317
 318                (start (match-beginning 0))
 319                (mine-start (match-end 0))
 320                (filename (match-string 1))
 321
 322                (_ (re-search-forward smerge-end-re))
 323                (_ (assert (< orig-point (match-end 0))))
 324
 325                (other-end (match-beginning 0))
 326                (end (match-end 0))
 327
 328                (_ (re-search-backward smerge-other-re start))
 329
 330                (mine-end (match-beginning 0))
 331                (other-start (match-end 0))
 332
 333                base-start base-end)
 334
 335           ;; handle the various conflict styles
 336           (cond
 337            ((re-search-backward smerge-base-re start t)
 338             ;; a 3-parts conflict
 339             (set (make-local-variable 'smerge-conflict-style) 'diff3-A)
 340             (setq base-end mine-end)
 341             (setq mine-end (match-beginning 0))
 342             (setq base-start (match-end 0)))
 343
 344           ((string= filename (file-name-nondirectory
 345                               (or buffer-file-name "")))
 346            ;; a 2-parts conflict
 347            (set (make-local-variable 'smerge-conflict-style) 'diff3-E))
 348
 349           ((and (not base-start)
 350                 (or (eq smerge-conflict-style 'diff3-A)
 351                     (string-match "^[.0-9]+\\'" filename)))
 352            ;; a same-diff conflict
 353            (setq base-start mine-start)
 354            (setq base-end   mine-end)
 355            (setq mine-start other-start)
 356            (setq mine-end   other-end)))
 357
 358           (store-match-data (list start end
 359                                   mine-start mine-end
 360                                   base-start base-end
 361                                   other-start other-end
 362                                   (when base-start (1- base-start)) base-start
 363                                   (1- other-start) other-start))
 364           t)
 365       (search-failed (error "Point not in conflict region")))))
 366
 367 (defun smerge-find-conflict (&optional limit)
 368   "Find and match a conflict region.  Intended as a font-lock MATCHER.
 369 The submatches are the same as in `smerge-match-conflict'.
 370 Returns non-nil if a match is found between the point and LIMIT.
 371 The point is moved to the end of the conflict."
 372   (when (re-search-forward smerge-begin-re limit t)
 373     (ignore-errors
 374       (smerge-match-conflict)
 375       (goto-char (match-end 0)))))
 376
 377 (defun smerge-diff (n1 n2)
 378   (smerge-match-conflict)
 379   (smerge-ensure-match n1)
 380   (smerge-ensure-match n2)
 381   (let ((name1 (aref smerge-match-names n1))
 382         (name2 (aref smerge-match-names n2))
 383         ;; Read them before the match-data gets clobbered.
 384         (beg1 (match-beginning n1))
 385         (end1 (match-end n1))
 386         (beg2 (match-beginning n2))
 387         (end2 (match-end n2))
 388         (file1 (make-temp-file "smerge1"))
 389         (file2 (make-temp-file "smerge2"))
 390         (dir default-directory)
 391         (file (file-relative-name buffer-file-name))
 392         (coding-system-for-read buffer-file-coding-system))
 393     (write-region beg1 end1 file1 nil 'nomessage)
 394     (write-region beg2 end2 file2 nil 'nomessage)
 395     (unwind-protect
 396         (with-current-buffer (get-buffer-create smerge-diff-buffer-name)
 397           (setq default-directory dir)
 398           (let ((inhibit-read-only t))
 399             (erase-buffer)
 400             (let ((status
 401                    (apply 'call-process diff-command nil t nil
 402                           (append smerge-diff-switches
 403                                   (list "-L" (concat name1 "/" file)
 404                                         "-L" (concat name2 "/" file)
 405                                         file1 file2)))))
 406               (if (eq status 0) (insert "No differences found.\n"))))
 407           (goto-char (point-min))
 408           (diff-mode)
 409           (display-buffer (current-buffer) t))
 410       (delete-file file1)
 411       (delete-file file2))))
 412
 413 ;; compiler pacifiers
 414 (defvar smerge-ediff-windows)
 415 (defvar smerge-ediff-buf)
 416 (defvar ediff-buffer-A)
 417 (defvar ediff-buffer-B)
 418 (defvar ediff-buffer-C)
 419
 420 (defun smerge-ediff ()
 421   "Invoke ediff to resolve the conflicts."
 422   (interactive)
 423   (let* ((buf (current-buffer))
 424          (mode major-mode)
 425          ;;(ediff-default-variant 'default-B)
 426          (config (current-window-configuration))
 427          (filename (file-name-nondirectory buffer-file-name))
 428          (mine (generate-new-buffer (concat "*" filename " MINE*")))
 429          (other (generate-new-buffer (concat "*" filename " OTHER*")))
 430          base)
 431     (with-current-buffer mine
 432       (buffer-disable-undo)
 433       (insert-buffer-substring buf)
 434       (goto-char (point-min))
 435       (while (smerge-find-conflict)
 436         (when (match-beginning 2) (setq base t))
 437         (replace-match (match-string 1) t t))
 438       (buffer-enable-undo)
 439       (set-buffer-modified-p nil)
 440       (funcall mode))
 441
 442     (with-current-buffer other
 443       (buffer-disable-undo)
 444       (insert-buffer-substring buf)
 445       (goto-char (point-min))
 446       (while (smerge-find-conflict)
 447         (replace-match (match-string 3) t t))
 448       (buffer-enable-undo)
 449       (set-buffer-modified-p nil)
 450       (funcall mode))
 451
 452     (when base
 453       (setq base (generate-new-buffer (concat "*" filename " BASE*")))
 454       (with-current-buffer base
 455         (buffer-disable-undo)
 456         (insert-buffer-substring buf)
 457         (goto-char (point-min))
 458         (while (smerge-find-conflict)
 459           (replace-match (or (match-string 2) "") t t))
 460         (buffer-enable-undo)
 461         (set-buffer-modified-p nil)
 462         (funcall mode)))
 463
 464     ;; the rest of the code is inspired from vc.el
 465     ;; Fire up ediff.
 466     (set-buffer
 467      (if base
 468          (ediff-merge-buffers-with-ancestor mine other base)
 469           ;; nil 'ediff-merge-revisions-with-ancestor buffer-file-name)
 470        (ediff-merge-buffers mine other)))
 471         ;; nil 'ediff-merge-revisions buffer-file-name)))
 472
 473     ;; Ediff is now set up, and we are in the control buffer.
 474     ;; Do a few further adjustments and take precautions for exit.
 475     (set (make-local-variable 'smerge-ediff-windows) config)
 476     (set (make-local-variable 'smerge-ediff-buf) buf)
 477     (set (make-local-variable 'ediff-quit-hook)
 478          (lambda ()
 479            (let ((buffer-A ediff-buffer-A)
 480                  (buffer-B ediff-buffer-B)
 481                  (buffer-C ediff-buffer-C)
 482                  (buffer-Ancestor ediff-ancestor-buffer)
 483                  (buf smerge-ediff-buf)
 484                  (windows smerge-ediff-windows))
 485              (ediff-cleanup-mess)
 486              (with-current-buffer buf
 487                (erase-buffer)
 488                (insert-buffer buffer-C)
 489                (kill-buffer buffer-A)
 490                (kill-buffer buffer-B)
 491                (kill-buffer buffer-C)
 492                (when (bufferp buffer-Ancestor) (kill-buffer buffer-Ancestor))
 493                (set-window-configuration windows)
 494                (message "Conflict resolution finished; you may save the buffer")))))
 495     (message "Please resolve conflicts now; exit ediff when done")))
 496
 497
 498 ;;;###autoload
 499 (define-minor-mode smerge-mode
 500   "Minor mode to simplify editing output from the diff3 program.
 501 \\{smerge-mode-map}"
 502   nil " SMerge" nil
 503   (when (and (boundp 'font-lock-mode) font-lock-mode)
 504     (set (make-local-variable 'font-lock-multiline) t)
 505     (save-excursion
 506       (if smerge-mode
 507           (font-lock-add-keywords nil smerge-font-lock-keywords 'append)
 508         (font-lock-remove-keywords nil smerge-font-lock-keywords))
 509       (goto-char (point-min))
 510       (while (smerge-find-conflict)
 511         (save-excursion
 512           (font-lock-fontify-region (match-beginning 0) (match-end 0) nil))))))
 513
 514
 515 (provide 'smerge-mode)
 516 ;;; smerge-mode.el ends here