lisp/ediff-merg.el

   1 ;;; ediff-merg.el --- merging utilities
   2
   3 ;; Copyright (C) 1994, 1995, 1996, 1997 Free Software Foundation, Inc.
   4
   5 ;; Author: Michael Kifer <kifer@cs.sunysb.edu>
   6
   7 ;; This file is part of GNU Emacs.
   8
   9 ;; GNU Emacs is free software; you can redistribute it and/or modify
  10 ;; it under the terms of the GNU General Public License as published by
  11 ;; the Free Software Foundation; either version 2, or (at your option)
  12 ;; any later version.
  13
  14 ;; GNU Emacs is distributed in the hope that it will be useful,
  15 ;; but WITHOUT ANY WARRANTY; without even the implied warranty of
  16 ;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  17 ;; GNU General Public License for more details.
  18
  19 ;; You should have received a copy of the GNU General Public License
  20 ;; along with GNU Emacs; see the file COPYING.  If not, write to the
  21 ;; Free Software Foundation, Inc., 59 Temple Place - Suite 330,
  22 ;; Boston, MA 02111-1307, USA.
  23
  24 ;;; Code:
  25
  26 (provide 'ediff-merg)
  27
  28 ;; compiler pacifier
  29 (defvar ediff-window-A)
  30 (defvar ediff-window-B)
  31 (defvar ediff-window-C)
  32 (defvar ediff-merge-window-share)
  33 (defvar ediff-window-config-saved)
  34
  35 (eval-when-compile
  36   (let ((load-path (cons (expand-file-name ".") load-path)))
  37     (or (featurep 'ediff-init)
  38         (load "ediff-init.el" nil nil 'nosuffix))
  39     (or (featurep 'ediff-util)
  40         (load "ediff-util.el" nil nil 'nosuffix))
  41     ))
  42 ;; end pacifier
  43
  44 (require 'ediff-init)
  45
  46 (defcustom ediff-quit-merge-hook 'ediff-maybe-save-and-delete-merge
  47   "*Hooks to run before quitting a merge job.
  48 The most common use is to save and delete the merge buffer."
  49   :type 'hook
  50   :group 'ediff-merge)
  51
  52
  53 (defcustom ediff-default-variant 'combined
  54   "*The variant to be used as a default for buffer C in merging.
  55 Valid values are the symbols `default-A', `default-B', and `combined'."
  56   :type '(radio (const default-A) (const default-B) (const combined))
  57   :group 'ediff-merge)
  58
  59 (defcustom ediff-combination-pattern
  60   '("<<<<<<< variant A" A ">>>>>>> variant B" B  "####### Ancestor" Ancestor "======= end")
  61   "*Pattern to be used for combining difference regions in buffers A and B.
  62 The value must be a list of the form
  63 (STRING1 bufspec1  STRING2 bufspec2 STRING3 bufspec3 STRING4)
  64 where bufspec is the symbol A, B, or Ancestor. For instance, if the value is
  65 '(STRING1 A  STRING2 Ancestor STRING3 B STRING4) then the
  66 combined text will look like this:
  67
  68 STRING1
  69 diff region from variant A
  70 STRING2
  71 diff region from the ancestor
  72 STRING3
  73 diff region from variant B
  74 STRING4
  75 "
  76   :type '(choice (list string symbol string symbol string)
  77                  (list string symbol string symbol string symbol string))
  78   :group 'ediff-merge)
  79
  80 (defcustom ediff-show-clashes-only nil
  81   "*If t, show only those diff regions where both buffers disagree with the ancestor.
  82 This means that regions that have status prefer-A or prefer-B will be
  83 skipped over.  Nil means show all regions."
  84   :type 'boolean
  85   :group 'ediff-merge
  86   )
  87 (make-variable-buffer-local 'ediff-show-clashes-only)
  88
  89 (defcustom ediff-skip-merge-regions-that-differ-from-default nil
  90   "*If t, show only the regions that have not been changed by the user.
  91 A region is considered to have been changed if it is different from the current
  92 default (`default-A', `default-B', `combined') and it hasn't been marked as
  93 `prefer-A' or `prefer-B'.
  94 A region is considered to have been changed also when it is marked as
  95 as `prefer-A', but is different from the corresponding difference region in
  96 Buffer A or if it is marked as `prefer-B' and is different from the region in
  97 Buffer B."
  98   :type 'boolean
  99   :group 'ediff-merge
 100   )
 101 (make-variable-buffer-local 'ediff-skip-merge-regions-that-differ-from-default)
 102
 103 ;; If ediff-show-clashes-only, check if there is no clash between the ancestor
 104 ;; and one of the variants.
 105 (defsubst ediff-merge-region-is-non-clash (n)
 106   (and ediff-show-clashes-only
 107        (string-match "prefer" (or (ediff-get-state-of-merge n) ""))))
 108
 109 ;; If ediff-skip-changed-regions, check if the merge region differs from
 110 ;; the current default. If a region is different from the default, it means
 111 ;; that the user has made determination as to how to merge for this particular
 112 ;; region.
 113 (defsubst ediff-skip-merge-region-if-changed-from-default-p (n)
 114   (and ediff-skip-merge-regions-that-differ-from-default
 115        (ediff-merge-changed-from-default-p n 'prefers-too)))
 116
 117
 118 (defun ediff-get-combined-region (n)
 119   (let ((pattern-list ediff-combination-pattern)
 120         (combo-region "")
 121         (err-msg
 122          "ediff-combination-pattern: Invalid format. Please consult the documentation")
 123         diff-region region-delim region-spec)
 124
 125     (if (< (length pattern-list) 5)
 126         (error err-msg))
 127
 128     (while (> (length pattern-list) 2)
 129       (setq region-delim (nth 0 pattern-list)
 130             region-spec (nth 1 pattern-list))
 131       (or (and (stringp region-delim) (memq region-spec '(A B Ancestor)))
 132           (error err-msg))
 133
 134       (condition-case err
 135           (setq combo-region
 136                 (concat combo-region
 137                         region-delim "\n"
 138                         (ediff-get-region-contents
 139                          n region-spec ediff-control-buffer)))
 140         (error ""))
 141       (setq pattern-list (cdr (cdr pattern-list)))
 142       )
 143
 144     (setq region-delim (nth 0 pattern-list))
 145     (or (stringp region-delim)
 146         (error err-msg))
 147     (setq combo-region (concat combo-region region-delim "\n"))
 148   ))
 149
 150 ;;(defsubst ediff-make-combined-diff (regA regB)
 151 ;;  (concat (nth 0 ediff-combination-pattern) "\n"
 152 ;;        regA
 153 ;;        (nth 1 ediff-combination-pattern) "\n"
 154 ;;        regB
 155 ;;        (nth 2 ediff-combination-pattern) "\n"))
 156
 157 (defsubst ediff-set-state-of-all-diffs-in-all-buffers (ctl-buf)
 158   (let ((n 0))
 159     (while (< n ediff-number-of-differences)
 160       (ediff-set-state-of-diff-in-all-buffers n ctl-buf)
 161       (setq n (1+ n)))))
 162
 163 (defun ediff-set-state-of-diff-in-all-buffers (n ctl-buf)
 164   (let ((regA (ediff-get-region-contents n 'A ctl-buf))
 165         (regB (ediff-get-region-contents n 'B ctl-buf))
 166         (regC (ediff-get-region-contents n 'C ctl-buf)))
 167     (cond ((and (string= regA regB) (string= regA  regC))
 168            (ediff-set-state-of-diff n 'A "=diff(B)")
 169            (ediff-set-state-of-diff n 'B "=diff(C)")
 170            (ediff-set-state-of-diff n 'C "=diff(A)"))
 171           ((string= regA regB)
 172            (ediff-set-state-of-diff n 'A "=diff(B)")
 173            (ediff-set-state-of-diff n 'B "=diff(A)")
 174            (ediff-set-state-of-diff n 'C nil))
 175           ((string= regA regC)
 176            (ediff-set-state-of-diff n 'A "=diff(C)")
 177            (ediff-set-state-of-diff n 'C "=diff(A)")
 178            (ediff-set-state-of-diff n 'B nil))
 179           ((string= regB regC)
 180            (ediff-set-state-of-diff n 'C "=diff(B)")
 181            (ediff-set-state-of-diff n 'B "=diff(C)")
 182            (ediff-set-state-of-diff n 'A nil))
 183           ((string= regC (ediff-get-combined-region n))
 184            (ediff-set-state-of-diff n 'A nil)
 185              (ediff-set-state-of-diff n 'B nil)
 186              (ediff-set-state-of-diff n 'C "=diff(A+B)"))
 187           (t (ediff-set-state-of-diff n 'A nil)
 188              (ediff-set-state-of-diff n 'B nil)
 189              (ediff-set-state-of-diff n 'C nil)))
 190     ))
 191
 192 (defun ediff-set-merge-mode ()
 193   (normal-mode t)
 194   (remove-hook 'local-write-file-hooks 'ediff-set-merge-mode))
 195
 196
 197 ;; Go over all diffs starting with DIFF-NUM and copy regions into buffer C
 198 ;; according to the state of the difference.
 199 ;; Since ediff-copy-diff refuses to copy identical diff regions, there is
 200 ;; no need to optimize ediff-do-merge any further.
 201 ;;
 202 ;; If re-merging, change state of merge in all diffs starting with
 203 ;; DIFF-NUM, except those where the state is prefer-* or where it is
 204 ;; `default-*' or `combined' but the buf C region appears to be modified
 205 ;; since last set by default.
 206 (defun ediff-do-merge (diff-num &optional remerging)
 207   (if (< diff-num 0) (setq diff-num 0))
 208   (let ((n diff-num)
 209         ;;(default-state-of-merge (format "%S" ediff-default-variant))
 210         do-not-copy state-of-merge)
 211     (while (< n ediff-number-of-differences)
 212       (setq do-not-copy nil) ; reset after each cycle
 213       (if (= (mod n 10) 0)
 214           (message "%s buffers A & B into C ... region %d of %d"
 215                    (if remerging "Re-merging" "Merging")
 216                    n
 217                    ediff-number-of-differences))
 218
 219       (setq state-of-merge (ediff-get-state-of-merge n))
 220
 221       (if remerging
 222           (let ((reg-A (ediff-get-region-contents n 'A ediff-control-buffer))
 223                 (reg-B (ediff-get-region-contents n 'B ediff-control-buffer))
 224                 (reg-C (ediff-get-region-contents n 'C ediff-control-buffer)))
 225
 226             ;; if region was edited since it was first set by default
 227             (if (or (ediff-merge-changed-from-default-p n)
 228                     ;; was preferred
 229                     (string-match "prefer" state-of-merge))
 230                 ;; then ignore
 231                 (setq do-not-copy t))
 232
 233             ;; change state of merge for this diff, if necessary
 234             (if (and (string-match "\\(default\\|combined\\)" state-of-merge)
 235                      (not do-not-copy))
 236                 (ediff-set-state-of-merge
 237                  n (format "%S" ediff-default-variant)))
 238             ))
 239
 240       ;; state-of-merge may have changed via ediff-set-state-of-merge, so
 241       ;; check it once again
 242       (setq state-of-merge (ediff-get-state-of-merge n))
 243
 244       (or do-not-copy
 245           (if (string= state-of-merge "combined")
 246               ;; use n+1 because ediff-combine-diffs works via user numbering
 247               ;; of diffs, which is 1+ to what ediff uses internally
 248               (ediff-combine-diffs (1+ n) 'batch)
 249             (ediff-copy-diff
 250              n (if (string-match "-A" state-of-merge) 'A 'B) 'C 'batch)))
 251       (setq n (1+ n)))
 252     (message "Merging buffers A & B into C ... Done")
 253     ))
 254
 255
 256 (defun ediff-re-merge ()
 257   "Remerge unmodified diff regions using a new default.  Start with the current region."
 258   (interactive)
 259   (let* ((default-variant-alist
 260            (list '("default-A") '("default-B") '("combined")))
 261          (actual-alist
 262           (delete (list (symbol-name ediff-default-variant))
 263                   default-variant-alist)))
 264     (setq ediff-default-variant
 265           (intern
 266            (completing-read
 267             (format "Current merge default is `%S'.  New default: "
 268                     ediff-default-variant)
 269             actual-alist nil 'must-match)))
 270     (ediff-do-merge ediff-current-difference 'remerge)
 271     (ediff-recenter)
 272   ))
 273
 274 (defun ediff-shrink-window-C (arg)
 275   "Shrink window C to just one line.
 276 With a prefix argument, returns window C to its normal size.
 277 Used only for merging jobs."
 278   (interactive "P")
 279   (if (not ediff-merge-job)
 280       (error "ediff-shrink-window-C can be used only for merging jobs"))
 281   (cond ((eq arg '-) (setq arg -1))
 282         ((not (numberp arg)) (setq arg nil)))
 283   (cond ((null arg)
 284          (let ((ediff-merge-window-share
 285                 (if (< (window-height ediff-window-C) 3)
 286                     ediff-merge-window-share 0)))
 287            (setq ediff-window-config-saved "") ; force redisplay
 288            (ediff-recenter 'no-rehighlight)))
 289         ((and (< arg 0) (> (window-height ediff-window-C) 2))
 290          (setq ediff-merge-window-share (* ediff-merge-window-share 0.9))
 291          (setq ediff-window-config-saved "") ; force redisplay
 292          (ediff-recenter 'no-rehighlight))
 293         ((and (> arg 0) (> (window-height ediff-window-A) 2))
 294          (setq ediff-merge-window-share (* ediff-merge-window-share 1.1))
 295          (setq ediff-window-config-saved "") ; force redisplay
 296          (ediff-recenter 'no-rehighlight))))
 297
 298
 299 ;; N here is the user's region number.  It is 1+ what Ediff uses internally.
 300 (defun ediff-combine-diffs (n &optional batch-invocation)
 301   "Combine Nth diff regions of buffers A and B and place the combination in C.
 302 N is a prefix argument.  If nil, combine the current difference regions.
 303 Combining is done according to the specifications in variable
 304 `ediff-combination-pattern'."
 305   (interactive "P")
 306   (setq n (if (numberp n) (1- n) ediff-current-difference))
 307
 308   (let (regA regB reg-combined)
 309     ;;(setq regA (ediff-get-region-contents n 'A ediff-control-buffer)
 310     ;;    regB (ediff-get-region-contents n 'B ediff-control-buffer))
 311     ;;(setq reg-combined (ediff-make-combined-diff regA regB))
 312     (setq reg-combined (ediff-get-combined-region n))
 313
 314     (ediff-copy-diff n nil 'C batch-invocation reg-combined))
 315     (or batch-invocation (ediff-jump-to-difference (1+ n))))
 316
 317
 318 ;; Checks if the region in buff C looks like a combination of the regions
 319 ;; in buffers A and B.  Return a list (reg-a-beg reg-a-end reg-b-beg reg-b-end)
 320 ;; These refer to where the delimiters for region A, B, Ancestor start and end
 321 ;; in buffer C
 322 (defun ediff-looks-like-combined-merge (region-num)
 323   (if ediff-merge-job
 324       (let ((combined (string-match (regexp-quote "(A+B)")
 325                                     (or (ediff-get-state-of-diff region-num 'C)
 326                                         "")))
 327             (mrgreg-beg (ediff-get-diff-posn 'C 'beg region-num))
 328             (mrgreg-end (ediff-get-diff-posn 'C 'end region-num))
 329             (pattern-list ediff-combination-pattern)
 330             delim reg-beg reg-end delim-regs-list)
 331
 332         (if combined
 333             (ediff-with-current-buffer ediff-buffer-C
 334               (while pattern-list
 335                 (goto-char mrgreg-beg)
 336                 (setq delim (nth 0 pattern-list))
 337                 (search-forward delim mrgreg-end 'noerror)
 338                 (setq reg-beg (match-beginning 0))
 339                 (setq reg-end (match-end 0))
 340                 (if (and reg-beg reg-end)
 341                     (setq delim-regs-list
 342                           ;; in reverse
 343                           (cons reg-end (cons reg-beg delim-regs-list))))
 344                 (if (> (length pattern-list) 1)
 345                     (setq pattern-list (cdr (cdr pattern-list)))
 346                   (setq pattern-list nil))
 347                 )))
 348
 349         (reverse delim-regs-list)
 350         )))
 351
 352 (eval-when-compile (defvar state-of-merge)) ; dynamic var
 353
 354 ;; Check if the non-preferred merge has been modified since originally set.
 355 ;; This affects only the regions that are marked as default-A/B or combined.
 356 ;; If PREFERS-TOO is non-nil, then look at the regions marked as prefers-A/B as
 357 ;; well.
 358 (defun ediff-merge-changed-from-default-p (diff-num &optional prefers-too)
 359   (let ((reg-A (ediff-get-region-contents diff-num 'A ediff-control-buffer))
 360         (reg-B (ediff-get-region-contents diff-num 'B ediff-control-buffer))
 361         (reg-C (ediff-get-region-contents diff-num 'C ediff-control-buffer)))
 362
 363     (setq state-of-merge (ediff-get-state-of-merge diff-num))
 364
 365     ;; if region was edited since it was first set by default
 366     (or (and (string= state-of-merge "default-A")
 367              (not (string= reg-A reg-C)))
 368         (and (string= state-of-merge "default-B")
 369              (not (string= reg-B reg-C)))
 370         (and (string= state-of-merge "combined")
 371              ;;(not (string= (ediff-make-combined-diff reg-A reg-B) reg-C)))
 372              (not (string= (ediff-get-combined-region diff-num) reg-C)))
 373         (and prefers-too
 374              (string= state-of-merge "prefer-A")
 375              (not (string= reg-A reg-C)))
 376         (and prefers-too
 377              (string= state-of-merge "prefer-B")
 378              (not (string= reg-B reg-C)))
 379         )))
 380
 381
 382 ;;; Local Variables:
 383 ;;; eval: (put 'ediff-defvar-local 'lisp-indent-hook 'defun)
 384 ;;; eval: (put 'ediff-with-current-buffer 'lisp-indent-hook 1)
 385 ;;; eval: (put 'ediff-with-current-buffer 'edebug-form-spec '(form body))
 386 ;;; End:
 387
 388 ;; ediff-merg.el ends here