lisp/smerge-mode.el

   1 ;;; smerge-mode.el --- Minor mode to resolve diff3 conflicts
   2
   3 ;; Copyright (C) 1999  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 1.1 1999/12/09 13:00:21 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-hooks '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 "*smerge-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   (list* "-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   '((t (:foreground "blue")))
  81   "Face for your code."
  82   :group 'smerge)
  83 (defvar smerge-mine-face 'smerge-mine-face)
  84
  85 (defface smerge-other-face
  86   '((t (:foreground "darkgreen")))
  87   "Face for the other code."
  88   :group 'smerge)
  89 (defvar smerge-other-face 'smerge-other-face)
  90
  91 (defface smerge-base-face
  92   '((t (:foreground "red")))
  93   "Face for the base code."
  94   :group 'smerge)
  95 (defvar smerge-base-face 'smerge-base-face)
  96
  97 (defface smerge-markers-face
  98   '((t (:background "grey85")))
  99   "Face for the conflict markers."
 100   :group 'smerge)
 101 (defvar smerge-markers-face 'smerge-markers-face)
 102
 103 (easy-mmode-defmap smerge-basic-map
 104   '(("n" . smerge-next)
 105     ("p" . smerge-prev)
 106     ("a" . smerge-keep-all)
 107     ("b" . smerge-keep-base)
 108     ("o" . smerge-keep-other)
 109     ("m" . smerge-keep-mine)
 110     ("E" . smerge-ediff)
 111     ("\C-m" . smerge-keep-current)
 112     ("d<" . smerge-diff-base-mine)
 113     ("d>" . smerge-diff-base-other)
 114     ("d=" . smerge-diff-mine-other))
 115   "The base keymap for `smerge-mode'.")
 116
 117 (defcustom smerge-command-prefix "\e"
 118   "Prefix for `smerge-mode' commands."
 119   :group 'smerge
 120   :type '(choice (string "\e") (string "C-x^") (string "") string))
 121
 122 (easy-mmode-defmap smerge-mode-map
 123   `((,smerge-command-prefix . ,smerge-basic-map))
 124   "Keymap for `smerge-mode'.")
 125
 126 (easy-menu-define smerge-mode-menu smerge-mode-map
 127   "Menu for `smerge-mode'."
 128   '("SMerge"
 129     ["Invoke Ediff"             smerge-ediff            t]
 130     ))
 131
 132 (defconst smerge-font-lock-keywords
 133   '((smerge-find-conflict
 134      (1 smerge-mine-face prepend)
 135      (2 smerge-base-face prepend t)
 136      (3 smerge-other-face prepend t)
 137      (0 smerge-markers-face keep)
 138      (4 nil t t)
 139      (5 nil t t)))
 140   "Font lock patterns for `smerge-mode'.")
 141
 142 (defconst smerge-begin-re "^<<<<<<< \\(.*\\)\n")
 143 (defconst smerge-end-re "^>>>>>>> .*\n")
 144 (defconst smerge-base-re "^||||||| .*\n")
 145 (defconst smerge-other-re "^=======\n")
 146
 147 (defvar smerge-conflict-style nil
 148   "Keep track of which style of conflict is in use.
 149 Can be nil if the style is undecided, or else:
 150 - `diff3-E'
 151 - `diff3-A'")
 152
 153 ;; Compiler pacifiers
 154 (defvar font-lock-mode nil)
 155 (defvar font-lock-keywords nil)
 156 (eval-when-compile
 157   (unless (fboundp 'font-lock-fontify-region)
 158     (autoload 'font-lock-fontify-region "font-lock")))
 159
 160 ;;;;
 161 ;;;; Actual code
 162 ;;;;
 163
 164 ;; Define smerge-next and smerge-prev
 165 (easy-mmode-define-navigation smerge smerge-begin-re "conflict")
 166
 167 (defconst smerge-match-names ["conflict" "mine" "base" "other"])
 168
 169 (defun smerge-ensure-match (n)
 170   (unless (match-end n)
 171     (error (format "No `%s'" (aref smerge-match-names n)))))
 172
 173 (defun smerge-auto-leave ()
 174   (when (and smerge-auto-leave
 175              (save-excursion (goto-char (point-min))
 176                              (not (re-search-forward smerge-begin-re nil t))))
 177     (smerge-mode -1)))
 178
 179
 180 (defun smerge-keep-all ()
 181   "Keep all three versions.
 182 Convenient for the kind of conflicts that can arise in ChangeLog files."
 183   (interactive)
 184   (smerge-match-conflict)
 185   (replace-match (concat (or (match-string 1) "")
 186                          (or (match-string 2) "")
 187                          (or (match-string 3) ""))
 188                  t t)
 189   (smerge-auto-leave))
 190
 191 (defun smerge-keep-base ()
 192   "Revert to the base version."
 193   (interactive)
 194   (smerge-match-conflict)
 195   (smerge-ensure-match 2)
 196   (replace-match (match-string 2) t t)
 197   (smerge-auto-leave))
 198
 199 (defun smerge-keep-other ()
 200   "Use \"other\" version."
 201   (interactive)
 202   (smerge-match-conflict)
 203   ;;(smerge-ensure-match 3)
 204   (replace-match (match-string 3) t t)
 205   (smerge-auto-leave))
 206
 207 (defun smerge-keep-mine ()
 208   "Keep your version."
 209   (interactive)
 210   (smerge-match-conflict)
 211   ;;(smerge-ensure-match 1)
 212   (replace-match (match-string 1) t t)
 213   (smerge-auto-leave))
 214
 215 (defun smerge-keep-current ()
 216   "Use the current (under the cursor) version."
 217   (interactive)
 218   (smerge-match-conflict)
 219   (let ((i 3))
 220     (while (or (not (match-end i))
 221                (< (point) (match-beginning i))
 222                (>= (point) (match-end i)))
 223       (decf i))
 224     (if (<= i 0) (error "Not inside a version")
 225       (replace-match (match-string i) t t)
 226       (smerge-auto-leave))))
 227
 228 (defun smerge-diff-base-mine ()
 229   "Diff 'base' and 'mine' version in current conflict region."
 230   (interactive)
 231   (smerge-diff 2 1))
 232
 233 (defun smerge-diff-base-other ()
 234   "Diff 'base' and 'other' version in current conflict region."
 235   (interactive)
 236   (smerge-diff 2 3))
 237
 238 (defun smerge-diff-mine-other ()
 239   "Diff 'mine' and 'other' version in current conflict region."
 240   (interactive)
 241   (smerge-diff 1 3))
 242
 243 (defun smerge-match-conflict ()
 244   "Get info about the conflict.  Puts the info in the `match-data'.
 245 The submatches contain:
 246  0:  the whole conflict.
 247  1:  your code.
 248  2:  the base code.
 249  3:  other code.
 250 An error is raised if not inside a conflict."
 251   (save-excursion
 252     (condition-case nil
 253         (let* ((orig-point (point))
 254
 255                (_ (forward-line 1))
 256                (_ (re-search-backward smerge-begin-re))
 257
 258                (start (match-beginning 0))
 259                (mine-start (match-end 0))
 260                (filename (match-string 1))
 261
 262                (_ (re-search-forward smerge-end-re))
 263                (_ (assert (< orig-point (match-end 0))))
 264
 265                (other-end (match-beginning 0))
 266                (end (match-end 0))
 267
 268                (_ (re-search-backward smerge-other-re start))
 269
 270                (mine-end (match-beginning 0))
 271                (other-start (match-end 0))
 272
 273                base-start base-end)
 274
 275           ;; handle the various conflict styles
 276           (cond
 277            ((re-search-backward smerge-base-re start t)
 278             ;; a 3-parts conflict
 279             (set (make-local-variable 'smerge-conflict-style) 'diff3-A)
 280             (setq base-end mine-end)
 281             (setq mine-end (match-beginning 0))
 282             (setq base-start (match-end 0)))
 283
 284           ((string= filename (file-name-nondirectory
 285                               (or buffer-file-name "")))
 286            ;; a 2-parts conflict
 287            (set (make-local-variable 'smerge-conflict-style) 'diff3-E))
 288
 289           ((and (not base-start)
 290                 (or (eq smerge-conflict-style 'diff3-A)
 291                     (string-match "^[.0-9]+\\'" filename)))
 292            ;; a same-diff conflict
 293            (setq base-start mine-start)
 294            (setq base-end   mine-end)
 295            (setq mine-start other-start)
 296            (setq mine-end   other-end)))
 297
 298           (store-match-data (list start end
 299                                   mine-start mine-end
 300                                   base-start base-end
 301                                   other-start other-end
 302                                   (when base-start (1- base-start)) base-start
 303                                   (1- other-start) other-start))
 304           t)
 305       (error "Point not in conflict region"))))
 306
 307 (defun smerge-find-conflict (&optional limit)
 308   "Find and match a conflict region.  Intended as a font-lock MATCHER.
 309 The submatches are the same as in `smerge-match-conflict'.
 310 Returns non-nil if a match is found between the point and LIMIT.
 311 The point is moved to the end of the conflict."
 312   (when (re-search-forward smerge-begin-re limit t)
 313     (ignore-errors
 314       (smerge-match-conflict)
 315       (goto-char (match-end 0)))))
 316
 317 (defun smerge-diff (n1 n2)
 318   (smerge-match-conflict)
 319   (smerge-ensure-match n1)
 320   (smerge-ensure-match n2)
 321   (let ((name1 (aref smerge-match-names n1))
 322         (name2 (aref smerge-match-names n2))
 323         (file1 (make-temp-file "smerge1"))
 324         (file2 (make-temp-file "smerge2")))
 325     (write-region (match-beginning n1) (match-end n1) file1)
 326     (write-region (match-beginning n2) (match-end n2) file2)
 327     (unwind-protect
 328         (with-current-buffer (get-buffer-create smerge-diff-buffer-name)
 329           (let ((inhibit-read-only t))
 330             (erase-buffer)
 331             (apply 'call-process diff-command nil t nil
 332                    (append smerge-diff-switches
 333                            (list "-L" name1 "-L" name2 file1 file2))))
 334           (goto-char (point-min))
 335           (diff-mode)
 336           (display-buffer (current-buffer) t))
 337       (delete-file file1)
 338       (delete-file file2))))
 339
 340 (eval-when-compile
 341   ;; compiler pacifiers
 342   (defvar smerge-ediff-windows)
 343   (defvar smerge-ediff-buf)
 344   (defvar ediff-buffer-A)
 345   (defvar ediff-buffer-B)
 346   (defvar ediff-buffer-C)
 347   (unless (fboundp 'ediff-cleanup-mess)
 348     (autoload 'ediff-cleanup-mess "ediff-util")))
 349
 350 (defun smerge-ediff ()
 351   "Invoke ediff to resolve the conflicts."
 352   (interactive)
 353   (let* ((buf (current-buffer))
 354          (mode major-mode)
 355          ;;(ediff-default-variant 'default-B)
 356          (config (current-window-configuration))
 357          (filename (file-name-nondirectory buffer-file-name))
 358          (mine (generate-new-buffer (concat "*" filename " MINE*")))
 359          (other (generate-new-buffer (concat "*" filename " OTHER*")))
 360          base)
 361     (with-current-buffer mine
 362       (buffer-disable-undo)
 363       (insert-buffer-substring buf)
 364       (goto-char (point-min))
 365       (while (smerge-find-conflict)
 366         (when (match-beginning 2) (setq base t))
 367         (replace-match (match-string 1) t t))
 368       (buffer-enable-undo)
 369       (set-buffer-modified-p nil)
 370       (funcall mode))
 371
 372     (with-current-buffer other
 373       (buffer-disable-undo)
 374       (insert-buffer-substring buf)
 375       (goto-char (point-min))
 376       (while (smerge-find-conflict)
 377         (replace-match (match-string 3) t t))
 378       (buffer-enable-undo)
 379       (set-buffer-modified-p nil)
 380       (funcall mode))
 381
 382     (when base
 383       (setq base (generate-new-buffer (concat "*" filename " BASE*")))
 384       (with-current-buffer base
 385         (buffer-disable-undo)
 386         (insert-buffer-substring buf)
 387         (goto-char (point-min))
 388         (while (smerge-find-conflict)
 389           (replace-match (or (match-string 2) "") t t))
 390         (buffer-enable-undo)
 391         (set-buffer-modified-p nil)
 392         (funcall mode)))
 393
 394     ;; the rest of the code is inspired from vc.el
 395     ;; Fire up ediff.
 396     (set-buffer
 397      (if base
 398          (ediff-merge-buffers-with-ancestor mine other base)
 399           ;; nil 'ediff-merge-revisions-with-ancestor buffer-file-name)
 400        (ediff-merge-buffers mine other)))
 401         ;; nil 'ediff-merge-revisions buffer-file-name)))
 402
 403     ;; Ediff is now set up, and we are in the control buffer.
 404     ;; Do a few further adjustments and take precautions for exit.
 405     (set (make-local-variable 'smerge-ediff-windows) config)
 406     (set (make-local-variable 'smerge-ediff-buf) buf)
 407     (set (make-local-variable 'ediff-quit-hook)
 408          (lambda ()
 409            (let ((buffer-A ediff-buffer-A)
 410                  (buffer-B ediff-buffer-B)
 411                  (buffer-C ediff-buffer-C)
 412                  (buffer-Ancestor ediff-ancestor-buffer)
 413                  (buf smerge-ediff-buf)
 414                  (windows smerge-ediff-windows))
 415              (ediff-cleanup-mess)
 416              (with-current-buffer buf
 417                (erase-buffer)
 418                (insert-buffer buffer-C)
 419                (kill-buffer buffer-A)
 420                (kill-buffer buffer-B)
 421                (kill-buffer buffer-C)
 422                (when (bufferp buffer-Ancestor) (kill-buffer buffer-Ancestor))
 423                (set-window-configuration windows)
 424                (message "Conflict resolution finished; you may save the buffer")))))
 425     (message "Please resolve conflicts now; exit ediff when done")))
 426
 427
 428 ;;;###autoload
 429 (define-minor-mode smerge-mode
 430   "Minor mode to simplify editing output from the diff3 program.
 431 \\{smerge-mode-map}"
 432   nil " SMerge" nil
 433   (when font-lock-mode
 434     (save-excursion
 435       (if smerge-mode
 436           (font-lock-add-keywords nil smerge-font-lock-keywords 'append)
 437         (font-lock-remove-keywords nil smerge-font-lock-keywords))
 438       (goto-char (point-min))
 439       (while (smerge-find-conflict)
 440         (font-lock-fontify-region (match-beginning 0) (match-end 0) nil)))))
 441
 442
 443 (provide 'smerge-mode)
 444
 445 ;;; Change Log:
 446 ;; $Log: smerge-mode.el,v $
 447 ;; Revision 1.1  1999/12/09 13:00:21  monnier
 448 ;; New file.  Provides a simple minor-mode for files containing
 449 ;; diff3-style conflict markers, such as generated by RCS
 450 ;;
 451
 452 ;;; smerge-mode.el ends here