lisp/ediff-merg.el

   1 ;;; ediff-merg.el --- merging utilities
   2
   3 ;; Copyright (C) 1994, 1995, 1996, 1997, 1998, 1999, 2000, 2001, 2002,
   4 ;;   2003, 2004, 2005, 2006, 2007, 2008 Free Software Foundation, Inc.
   5
   6 ;; Author: Michael Kifer <kifer@cs.stonybrook.edu>
   7
   8 ;; This file is part of GNU Emacs.
   9
  10 ;; GNU Emacs is free software; you can redistribute it and/or modify
  11 ;; it under the terms of the GNU General Public License as published by
  12 ;; the Free Software Foundation; either version 3, or (at your option)
  13 ;; any later version.
  14
  15 ;; GNU Emacs is distributed in the hope that it will be useful,
  16 ;; but WITHOUT ANY WARRANTY; without even the implied warranty of
  17 ;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  18 ;; GNU General Public License for more details.
  19
  20 ;; You should have received a copy of the GNU General Public License
  21 ;; along with GNU Emacs; see the file COPYING.  If not, write to the
  22 ;; Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
  23 ;; Boston, MA 02110-1301, USA.
  24
  25 ;;; Commentary:
  26
  27 ;;; Code:
  28
  29
  30 ;; compiler pacifier
  31 (defvar ediff-window-A)
  32 (defvar ediff-window-B)
  33 (defvar ediff-window-C)
  34 (defvar ediff-merge-window-share)
  35 (defvar ediff-window-config-saved)
  36
  37 (eval-when-compile
  38   (require 'ediff-init)
  39   (require 'ediff-util)
  40   )
  41 ;; end pacifier
  42
  43 (require 'ediff-init)
  44
  45 (defcustom ediff-quit-merge-hook 'ediff-maybe-save-and-delete-merge
  46   "*Hooks to run before quitting a merge job.
  47 The most common use is to save and delete the merge buffer."
  48   :type 'hook
  49   :group 'ediff-merge)
  50
  51
  52 (defcustom ediff-default-variant 'combined
  53   "*The variant to be used as a default for buffer C in merging.
  54 Valid values are the symbols `default-A', `default-B', and `combined'."
  55   :type '(radio (const default-A) (const default-B) (const combined))
  56   :group 'ediff-merge)
  57
  58 (defcustom ediff-combination-pattern
  59   '("<<<<<<< variant A" A ">>>>>>> variant B" B  "####### Ancestor" Ancestor "======= end")
  60   "*Pattern to be used for combining difference regions in buffers A and B.
  61 The value must be a list of the form
  62 \(STRING1 bufspec1  STRING2 bufspec2 STRING3 bufspec3 STRING4)
  63 where bufspec is the symbol A, B, or Ancestor. For instance, if the value is
  64 '(STRING1 A  STRING2 Ancestor STRING3 B STRING4) then the
  65 combined text will look like this:
  66
  67 STRING1
  68 diff region from variant A
  69 STRING2
  70 diff region from the ancestor
  71 STRING3
  72 diff region from variant B
  73 STRING4
  74 "
  75   :type '(choice (list string symbol string symbol string)
  76                  (list string symbol string symbol string symbol string))
  77   :group 'ediff-merge)
  78
  79 (defcustom ediff-show-clashes-only nil
  80   "*If t, show only those diff regions where both buffers disagree with the ancestor.
  81 This means that regions that have status prefer-A or prefer-B will be
  82 skipped over.  A value of nil means show all regions."
  83   :type 'boolean
  84   :group 'ediff-merge
  85   )
  86 (make-variable-buffer-local 'ediff-show-clashes-only)
  87
  88 (defcustom ediff-skip-merge-regions-that-differ-from-default nil
  89   "*If t, show only the regions that have not been changed by the user.
  90 A region is considered to have been changed if it is different from the current
  91 default (`default-A', `default-B', `combined') and it hasn't been marked as
  92 `prefer-A' or `prefer-B'.
  93 A region is considered to have been changed also when it is marked as
  94 as `prefer-A', but is different from the corresponding difference region in
  95 Buffer A or if it is marked as `prefer-B' and is different from the region in
  96 Buffer B."
  97   :type 'boolean
  98   :group 'ediff-merge
  99   )
 100 (make-variable-buffer-local 'ediff-skip-merge-regions-that-differ-from-default)
 101
 102 ;; check if there is no clash between the ancestor and one of the variants.
 103 ;; if it is not a merge job then return true
 104 (defsubst ediff-merge-region-is-non-clash (n)
 105   (if (ediff-merge-job)
 106       (string-match "prefer" (or (ediff-get-state-of-merge n) ""))
 107     t))
 108
 109 ;; If ediff-show-clashes-only, check if there is no clash between the ancestor
 110 ;; and one of the variants.
 111 (defsubst ediff-merge-region-is-non-clash-to-skip (n)
 112   (and ediff-show-clashes-only
 113        (ediff-merge-region-is-non-clash n)))
 114
 115 ;; If ediff-skip-changed-regions, check if the merge region differs from
 116 ;; the current default. If a region is different from the default, it means
 117 ;; that the user has made determination as to how to merge for this particular
 118 ;; region.
 119 (defsubst ediff-skip-merge-region-if-changed-from-default-p (n)
 120   (and ediff-skip-merge-regions-that-differ-from-default
 121        (ediff-merge-changed-from-default-p n 'prefers-too)))
 122
 123
 124 (defun ediff-get-combined-region (n)
 125   (let ((pattern-list ediff-combination-pattern)
 126         (combo-region "")
 127         (err-msg
 128          "ediff-combination-pattern: Invalid format. Please consult the documentation")
 129         region-delim region-spec)
 130
 131     (if (< (length pattern-list) 5)
 132         (error err-msg))
 133
 134     (while (> (length pattern-list) 2)
 135       (setq region-delim (nth 0 pattern-list)
 136             region-spec (nth 1 pattern-list))
 137       (or (and (stringp region-delim) (memq region-spec '(A B Ancestor)))
 138           (error err-msg))
 139
 140       (condition-case nil
 141           (setq combo-region
 142                 (concat combo-region
 143                         region-delim "\n"
 144                         (ediff-get-region-contents
 145                          n region-spec ediff-control-buffer)))
 146         (error ""))
 147       (setq pattern-list (cdr (cdr pattern-list)))
 148       )
 149
 150     (setq region-delim (nth 0 pattern-list))
 151     (or (stringp region-delim)
 152         (error err-msg))
 153     (setq combo-region (concat combo-region region-delim "\n"))
 154   ))
 155
 156 ;;(defsubst ediff-make-combined-diff (regA regB)
 157 ;;  (concat (nth 0 ediff-combination-pattern) "\n"
 158 ;;        regA
 159 ;;        (nth 1 ediff-combination-pattern) "\n"
 160 ;;        regB
 161 ;;        (nth 2 ediff-combination-pattern) "\n"))
 162
 163 (defsubst ediff-set-state-of-all-diffs-in-all-buffers (ctl-buf)
 164   (let ((n 0))
 165     (while (< n ediff-number-of-differences)
 166       (ediff-set-state-of-diff-in-all-buffers n ctl-buf)
 167       (setq n (1+ n)))))
 168
 169 (defun ediff-set-state-of-diff-in-all-buffers (n ctl-buf)
 170   (let ((regA (ediff-get-region-contents n 'A ctl-buf))
 171         (regB (ediff-get-region-contents n 'B ctl-buf))
 172         (regC (ediff-get-region-contents n 'C ctl-buf)))
 173     (cond ((and (string= regA regB) (string= regA  regC))
 174            (ediff-set-state-of-diff n 'A "=diff(B)")
 175            (ediff-set-state-of-diff n 'B "=diff(C)")
 176            (ediff-set-state-of-diff n 'C "=diff(A)"))
 177           ((string= regA regB)
 178            (ediff-set-state-of-diff n 'A "=diff(B)")
 179            (ediff-set-state-of-diff n 'B "=diff(A)")
 180            (ediff-set-state-of-diff n 'C nil))
 181           ((string= regA regC)
 182            (ediff-set-state-of-diff n 'A "=diff(C)")
 183            (ediff-set-state-of-diff n 'C "=diff(A)")
 184            (ediff-set-state-of-diff n 'B nil))
 185           ((string= regB regC)
 186            (ediff-set-state-of-diff n 'C "=diff(B)")
 187            (ediff-set-state-of-diff n 'B "=diff(C)")
 188            (ediff-set-state-of-diff n 'A nil))
 189           ((string= regC (ediff-get-combined-region n))
 190            (ediff-set-state-of-diff n 'A nil)
 191              (ediff-set-state-of-diff n 'B nil)
 192              (ediff-set-state-of-diff n 'C "=diff(A+B)"))
 193           (t (ediff-set-state-of-diff n 'A nil)
 194              (ediff-set-state-of-diff n 'B nil)
 195              (ediff-set-state-of-diff n 'C nil)))
 196     ))
 197
 198 (defun ediff-set-merge-mode ()
 199   (normal-mode t)
 200   (remove-hook 'local-write-file-hooks 'ediff-set-merge-mode))
 201
 202
 203 ;; Go over all diffs starting with DIFF-NUM and copy regions into buffer C
 204 ;; according to the state of the difference.
 205 ;; Since ediff-copy-diff refuses to copy identical diff regions, there is
 206 ;; no need to optimize ediff-do-merge any further.
 207 ;;
 208 ;; If re-merging, change state of merge in all diffs starting with
 209 ;; DIFF-NUM, except those where the state is prefer-* or where it is
 210 ;; `default-*' or `combined' but the buf C region appears to be modified
 211 ;; since last set by default.
 212 (defun ediff-do-merge (diff-num &optional remerging)
 213   (if (< diff-num 0) (setq diff-num 0))
 214   (let ((n diff-num)
 215         ;;(default-state-of-merge (format "%S" ediff-default-variant))
 216         do-not-copy state-of-merge)
 217     (while (< n ediff-number-of-differences)
 218       (setq do-not-copy nil) ; reset after each cycle
 219       (if (= (mod n 10) 0)
 220           (message "%s buffers A & B into C ... region %d of %d"
 221                    (if remerging "Re-merging" "Merging")
 222                    n
 223                    ediff-number-of-differences))
 224
 225       (setq state-of-merge (ediff-get-state-of-merge n))
 226
 227       (if remerging
 228           ;;(let ((reg-A (ediff-get-region-contents n 'A ediff-control-buffer))
 229           ;;    (reg-B (ediff-get-region-contents n 'B ediff-control-buffer))
 230           ;;    (reg-C (ediff-get-region-contents n 'C ediff-control-buffer)))
 231           (let ()
 232
 233             ;; if region was edited since it was first set by default
 234             (if (or (ediff-merge-changed-from-default-p n)
 235                     ;; was preferred
 236                     (string-match "prefer" state-of-merge))
 237                 ;; then ignore
 238                 (setq do-not-copy t))
 239
 240             ;; change state of merge for this diff, if necessary
 241             (if (and (string-match "\\(default\\|combined\\)" state-of-merge)
 242                      (not do-not-copy))
 243                 (ediff-set-state-of-merge
 244                  n (format "%S" ediff-default-variant)))
 245             ))
 246
 247       ;; state-of-merge may have changed via ediff-set-state-of-merge, so
 248       ;; check it once again
 249       (setq state-of-merge (ediff-get-state-of-merge n))
 250
 251       (or do-not-copy
 252           (if (string= state-of-merge "combined")
 253               ;; use n+1 because ediff-combine-diffs works via user numbering
 254               ;; of diffs, which is 1+ to what ediff uses internally
 255               (ediff-combine-diffs (1+ n) 'batch)
 256             (ediff-copy-diff
 257              n (if (string-match "-A" state-of-merge) 'A 'B) 'C 'batch)))
 258       (setq n (1+ n)))
 259     (message "Merging buffers A & B into C ... Done")
 260     ))
 261
 262
 263 (defun ediff-re-merge ()
 264   "Remerge unmodified diff regions using a new default.  Start with the current region."
 265   (interactive)
 266   (let* ((default-variant-alist
 267            (list '("default-A") '("default-B") '("combined")))
 268          (actual-alist
 269           (delete (list (symbol-name ediff-default-variant))
 270                   default-variant-alist)))
 271     (setq ediff-default-variant
 272           (intern
 273            (completing-read
 274             (format "Current merge default is `%S'.  New default: "
 275                     ediff-default-variant)
 276             actual-alist nil 'must-match)))
 277     (ediff-do-merge ediff-current-difference 'remerge)
 278     (ediff-recenter)
 279   ))
 280
 281 (defun ediff-shrink-window-C (arg)
 282   "Shrink window C to just one line.
 283 With a prefix argument, returns window C to its normal size.
 284 Used only for merging jobs."
 285   (interactive "P")
 286   (if (not ediff-merge-job)
 287       (error "ediff-shrink-window-C can be used only for merging jobs"))
 288   (cond ((eq arg '-) (setq arg -1))
 289         ((not (numberp arg)) (setq arg nil)))
 290   (cond ((null arg)
 291          (let ((ediff-merge-window-share
 292                 (if (< (window-height ediff-window-C) 3)
 293                     ediff-merge-window-share 0)))
 294            (setq ediff-window-config-saved "") ; force redisplay
 295            (ediff-recenter 'no-rehighlight)))
 296         ((and (< arg 0) (> (window-height ediff-window-C) 2))
 297          (setq ediff-merge-window-share (* ediff-merge-window-share 0.9))
 298          (setq ediff-window-config-saved "") ; force redisplay
 299          (ediff-recenter 'no-rehighlight))
 300         ((and (> arg 0) (> (window-height ediff-window-A) 2))
 301          (setq ediff-merge-window-share (* ediff-merge-window-share 1.1))
 302          (setq ediff-window-config-saved "") ; force redisplay
 303          (ediff-recenter 'no-rehighlight))))
 304
 305
 306 ;; N here is the user's region number.  It is 1+ what Ediff uses internally.
 307 (defun ediff-combine-diffs (n &optional batch-invocation)
 308   "Combine Nth diff regions of buffers A and B and place the combination in C.
 309 N is a prefix argument.  If nil, combine the current difference regions.
 310 Combining is done according to the specifications in variable
 311 `ediff-combination-pattern'."
 312   (interactive "P")
 313   (setq n (if (numberp n) (1- n) ediff-current-difference))
 314
 315   (let (reg-combined)
 316     ;;(setq regA (ediff-get-region-contents n 'A ediff-control-buffer)
 317     ;;    regB (ediff-get-region-contents n 'B ediff-control-buffer))
 318     ;;(setq reg-combined (ediff-make-combined-diff regA regB))
 319     (setq reg-combined (ediff-get-combined-region n))
 320
 321     (ediff-copy-diff n nil 'C batch-invocation reg-combined))
 322     (or batch-invocation (ediff-jump-to-difference (1+ n))))
 323
 324
 325 ;; Checks if the region in buff C looks like a combination of the regions
 326 ;; in buffers A and B.  Return a list (reg-a-beg reg-a-end reg-b-beg reg-b-end)
 327 ;; These refer to where the delimiters for region A, B, Ancestor start and end
 328 ;; in buffer C
 329 (defun ediff-looks-like-combined-merge (region-num)
 330   (if ediff-merge-job
 331       (let ((combined (string-match (regexp-quote "(A+B)")
 332                                     (or (ediff-get-state-of-diff region-num 'C)
 333                                         "")))
 334             (mrgreg-beg (ediff-get-diff-posn 'C 'beg region-num))
 335             (mrgreg-end (ediff-get-diff-posn 'C 'end region-num))
 336             (pattern-list ediff-combination-pattern)
 337             delim reg-beg reg-end delim-regs-list)
 338
 339         (if combined
 340             (ediff-with-current-buffer ediff-buffer-C
 341               (while pattern-list
 342                 (goto-char mrgreg-beg)
 343                 (setq delim (nth 0 pattern-list))
 344                 (search-forward delim mrgreg-end 'noerror)
 345                 (setq reg-beg (match-beginning 0))
 346                 (setq reg-end (match-end 0))
 347                 (if (and reg-beg reg-end)
 348                     (setq delim-regs-list
 349                           ;; in reverse
 350                           (cons reg-end (cons reg-beg delim-regs-list))))
 351                 (if (> (length pattern-list) 1)
 352                     (setq pattern-list (cdr (cdr pattern-list)))
 353                   (setq pattern-list nil))
 354                 )))
 355
 356         (reverse delim-regs-list)
 357         )))
 358
 359 (eval-when-compile (defvar state-of-merge)) ; dynamic var
 360
 361 ;; Check if the non-preferred merge has been modified since originally set.
 362 ;; This affects only the regions that are marked as default-A/B or combined.
 363 ;; If PREFERS-TOO is non-nil, then look at the regions marked as prefers-A/B as
 364 ;; well.
 365 (defun ediff-merge-changed-from-default-p (diff-num &optional prefers-too)
 366   (let ((reg-A (ediff-get-region-contents diff-num 'A ediff-control-buffer))
 367         (reg-B (ediff-get-region-contents diff-num 'B ediff-control-buffer))
 368         (reg-C (ediff-get-region-contents diff-num 'C ediff-control-buffer)))
 369
 370     (setq state-of-merge (ediff-get-state-of-merge diff-num))
 371
 372     ;; if region was edited since it was first set by default
 373     (or (and (string= state-of-merge "default-A")
 374              (not (string= reg-A reg-C)))
 375         (and (string= state-of-merge "default-B")
 376              (not (string= reg-B reg-C)))
 377         (and (string= state-of-merge "combined")
 378              ;;(not (string= (ediff-make-combined-diff reg-A reg-B) reg-C)))
 379              (not (string= (ediff-get-combined-region diff-num) reg-C)))
 380         (and prefers-too
 381              (string= state-of-merge "prefer-A")
 382              (not (string= reg-A reg-C)))
 383         (and prefers-too
 384              (string= state-of-merge "prefer-B")
 385              (not (string= reg-B reg-C)))
 386         )))
 387
 388
 389 (provide 'ediff-merg)
 390
 391
 392 ;;; Local Variables:
 393 ;;; eval: (put 'ediff-defvar-local 'lisp-indent-hook 'defun)
 394 ;;; eval: (put 'ediff-with-current-buffer 'lisp-indent-hook 1)
 395 ;;; eval: (put 'ediff-with-current-buffer 'edebug-form-spec '(form body))
 396 ;;; End:
 397
 398 ;;; arch-tag: 9b798cf9-02ba-487f-a62e-b63aa823dbfb
 399 ;;; ediff-merg.el ends here