lisp/ediff-merg.el

   1 ;;; ediff-merg.el --- merging utilities
   2 ;;; Copyright (C) 1994, 1995 Free Software Foundation, Inc.
   3
   4 ;; Author: Michael Kifer <kifer@cs.sunysb.edu>
   5
   6 ;; This file is part of GNU Emacs.
   7
   8 ;; GNU Emacs is free software; you can redistribute it and/or modify
   9 ;; it under the terms of the GNU General Public License as published by
  10 ;; the Free Software Foundation; either version 2, or (at your option)
  11 ;; any later version.
  12
  13 ;; GNU Emacs is distributed in the hope that it will be useful,
  14 ;; but WITHOUT ANY WARRANTY; without even the implied warranty of
  15 ;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16 ;; GNU General Public License for more details.
  17
  18 ;; You should have received a copy of the GNU General Public License
  19 ;; along with GNU Emacs; see the file COPYING.  If not, write to
  20 ;; the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA.
  21
  22
  23 (require 'ediff-init)
  24
  25 (defvar ediff-default-variant 'default-A
  26   "*The variant to be used as a default for buffer C in merging.
  27 Valid values are the symbols `default-A', `default-B', and `combined'.")
  28
  29 (defvar ediff-combination-pattern
  30   '("#ifdef NEW /* variant A */" "#else /* variant B */" "#endif /* NEW */")
  31   "*Pattern to be used for combining difference regions in buffers A and B.
  32 The value is (STRING1 STRING2 STRING3). The combined text will look like this:
  33
  34 STRING1
  35 diff region from variant A
  36 STRING2
  37 diff region from variant B
  38 STRING3
  39 ")
  40
  41 (ediff-defvar-local ediff-show-clashes-only  nil
  42   "*If t, show only those diff regions where both buffers disagree with the ancestor.
  43 This means that regions that have status prefer-A or prefer-B will be
  44 skiped over. Nil means show all regions.")
  45
  46
  47 (defsubst ediff-get-combined-region (n)
  48   (concat (nth 0 ediff-combination-pattern) "\n"
  49           (ediff-get-region-contents n 'A ediff-control-buffer)
  50           (nth 1 ediff-combination-pattern) "\n"
  51           (ediff-get-region-contents n 'B ediff-control-buffer)
  52           (nth 2 ediff-combination-pattern) "\n"))
  53
  54 (defsubst ediff-set-state-of-all-diffs-in-all-buffers (ctl-buf)
  55   (let ((n 0))
  56     (while (< n ediff-number-of-differences)
  57       (ediff-set-state-of-diff-in-all-buffers n ctl-buf)
  58       (setq n (1+ n)))))
  59
  60 (defun ediff-set-state-of-diff-in-all-buffers (n ctl-buf)
  61   (let ((regA (ediff-get-region-contents n 'A ctl-buf))
  62         (regB (ediff-get-region-contents n 'B ctl-buf))
  63         (regC (ediff-get-region-contents n 'C ctl-buf)))
  64     (cond ((and (string= regA regB) (string= regA  regC))
  65            (ediff-set-state-of-diff n 'A "=diff(B)")
  66            (ediff-set-state-of-diff n 'B "=diff(C)")
  67            (ediff-set-state-of-diff n 'C "=diff(A)"))
  68           ((string= regA regB)
  69            (ediff-set-state-of-diff n 'A "=diff(B)")
  70            (ediff-set-state-of-diff n 'B "=diff(A)")
  71            (ediff-set-state-of-diff n 'C nil))
  72           ((string= regA regC)
  73            (ediff-set-state-of-diff n 'A "=diff(C)")
  74            (ediff-set-state-of-diff n 'C "=diff(A)")
  75            (ediff-set-state-of-diff n 'B nil))
  76           ((string= regB regC)
  77            (ediff-set-state-of-diff n 'C "=diff(B)")
  78            (ediff-set-state-of-diff n 'B "=diff(C)")
  79            (ediff-set-state-of-diff n 'A nil))
  80           ((string= regC (ediff-get-combined-region n))
  81            (ediff-set-state-of-diff n 'A nil)
  82              (ediff-set-state-of-diff n 'B nil)
  83              (ediff-set-state-of-diff n 'C "=diff(A+B)"))
  84           (t (ediff-set-state-of-diff n 'A nil)
  85              (ediff-set-state-of-diff n 'B nil)
  86              (ediff-set-state-of-diff n 'C nil)))
  87     ))
  88
  89 (defun ediff-set-merge-mode ()
  90   ;; by Stig@hackvan.com
  91   (normal-mode t)
  92   (remove-hook 'local-write-file-hooks 'ediff-set-merge-mode))
  93
  94 ;; Go over all diffs starting with DIFF-NUM and copy regions into buffer C
  95 ;; according to the state of the difference.
  96 ;; Since ediff-copy-diff refuses to copy identical diff regions, there is
  97 ;; no need to optimize ediff-do-merge any further.
  98 ;;
  99 ;; If re-merging, change state of merge in all diffs starting with
 100 ;; DIFF-NUM, except those where the state is prefer-* or where it is
 101 ;; `default-*' or `combined' but the buf C region appears to be modified
 102 ;; since last set by default.
 103 (defun ediff-do-merge (diff-num &optional remerging)
 104   (if (< diff-num 0) (setq diff-num 0))
 105   (let ((n diff-num)
 106         (default-state-of-merge (format "%S" ediff-default-variant))
 107         do-not-copy state-of-merge)
 108     (while (< n ediff-number-of-differences)
 109       (if (= (mod n 10) 0)
 110           (message "%s buffers A & B into C ... region %d of %d"
 111                    (if remerging "Re-merging" "Merging")
 112                    n
 113                    ediff-number-of-differences))
 114
 115       (setq state-of-merge (ediff-get-state-of-merge n))
 116       (setq do-not-copy (string= state-of-merge default-state-of-merge))
 117
 118       (if remerging
 119           (let ((reg-A (ediff-get-region-contents n 'A ediff-control-buffer))
 120                 (reg-B (ediff-get-region-contents n 'B ediff-control-buffer))
 121                 (reg-C (ediff-get-region-contents n 'C ediff-control-buffer)))
 122
 123                     ;;; was edited since first set by default
 124             (if (or (and (string= state-of-merge "default-A")
 125                       (not (string= reg-A reg-C)))
 126                     ;; was edited since first set by default
 127                     (and (string= state-of-merge "default-B")
 128                          (not (string= reg-B reg-C)))
 129                     ;; was edited since first set by default
 130                     (and (string= state-of-merge "combined")
 131                          (not (string=
 132                                (ediff-make-combined-diff reg-A reg-B) reg-C)))
 133                     ;; was prefered--ignore
 134                     (string-match "prefer" state-of-merge))
 135                 (setq do-not-copy t))
 136
 137             ;; change state of merge for this diff, if necessary
 138             (if (and (string-match "\\(default\\|combined\\)" state-of-merge)
 139                      (not do-not-copy))
 140                 (ediff-set-state-of-merge
 141                  n (format "%S" ediff-default-variant)))
 142             ))
 143
 144       ;; state-of-merge may have changed via ediff-set-state-of-merge, so
 145       ;; check it once again
 146       (setq state-of-merge (ediff-get-state-of-merge n))
 147
 148       (or do-not-copy
 149           (if (string= state-of-merge "combined")
 150               ;; use n+1 because ediff-combine-diffs works via user numbering
 151               ;; of diffs, which is 1+ to what ediff uses internally
 152               (ediff-combine-diffs (1+ n) 'batch)
 153             (ediff-copy-diff
 154              n (if (string-match "-A" state-of-merge) 'A 'B) 'C 'batch)))
 155       (setq n (1+ n)))
 156     (message "Merging buffers A & B into C ... Done")
 157     ))
 158
 159
 160 (defun ediff-re-merge ()
 161   "Remerge unmodified diff regions using a new default. Start with the current region."
 162   (interactive)
 163   (let* ((default-variant-alist
 164            (list '("default-A") '("default-B") '("combined")))
 165          (actual-alist
 166           (delete (list (symbol-name ediff-default-variant))
 167                   default-variant-alist)))
 168     (setq ediff-default-variant
 169           (intern
 170            (completing-read
 171             (format "Current merge default is `%S'. New default: "
 172                     ediff-default-variant)
 173             actual-alist nil 'must-match)))
 174     (ediff-do-merge ediff-current-difference 'remerge)
 175     (ediff-recenter)
 176   ))
 177
 178 (defun ediff-shrink-window-C (arg)
 179   "Shrink window C to just one line.
 180 With a prefix argument, returns window C to its normal size.
 181 Used only for merging jobs."
 182   (interactive "P")
 183   (if (not ediff-merge-job)
 184       (error "ediff-shrink-window-C can be used only for merging jobs"))
 185   (cond ((eq arg '-) (setq arg -1))
 186         ((not (numberp arg)) (setq arg nil)))
 187   (cond ((null arg)
 188          (let ((ediff-merge-window-share
 189                 (if (< (window-height ediff-window-C) 3)
 190                     ediff-merge-window-share 0)))
 191            (setq ediff-window-config-saved "") ; force redisplay
 192            (ediff-recenter 'no-rehighlight)))
 193         ((and (< arg 0) (> (window-height ediff-window-C) 2))
 194          (setq ediff-merge-window-share (* ediff-merge-window-share 0.9))
 195          (setq ediff-window-config-saved "") ; force redisplay
 196          (ediff-recenter 'no-rehighlight))
 197         ((and (> arg 0) (> (window-height ediff-window-A) 2))
 198          (setq ediff-merge-window-share (* ediff-merge-window-share 1.1))
 199          (setq ediff-window-config-saved "") ; force redisplay
 200          (ediff-recenter 'no-rehighlight))))
 201
 202
 203 ;; N here is the user's region number. It is 1+ what Ediff uses internally.
 204 (defun ediff-combine-diffs (n &optional batch-invocation)
 205   "Combine Nth diff regions of buffers A and B and place the combination in C.
 206 Combining is done using the list in variable `ediff-combination-pattern'."
 207   (interactive "P")
 208   (setq n (if n (1- n) ediff-current-difference))
 209
 210   (let (regA regB reg-combined)
 211     (setq regA (ediff-get-region-contents n 'A ediff-control-buffer)
 212           regB (ediff-get-region-contents n 'B ediff-control-buffer))
 213
 214     (setq reg-combined (ediff-make-combined-diff regA regB))
 215
 216     (ediff-copy-diff n nil 'C batch-invocation reg-combined))
 217     (or batch-invocation (ediff-recenter)))
 218
 219 (defsubst ediff-make-combined-diff (regA regB)
 220   (concat (nth 0 ediff-combination-pattern) "\n"
 221           regA
 222           (nth 1 ediff-combination-pattern) "\n"
 223           regB
 224           (nth 2 ediff-combination-pattern) "\n"))
 225
 226
 227 ;; Checks if the region in buff C looks like a combination of the regions
 228 ;; in buffers A and B. Returns a list (reg-a-beg reg-a-end reg-b-beg reg-b-end)
 229 ;; These refer to where the copies of region A and B start and end in buffer C
 230 (defun ediff-looks-like-combined-merge (region-num)
 231   (if ediff-merge-job
 232       (let ((combined (string-match (regexp-quote "(A+B)")
 233                                     (or (ediff-get-state-of-diff region-num 'C)
 234                                         "")))
 235             (reg-beg (ediff-get-diff-posn 'C 'beg region-num))
 236             (reg-end (ediff-get-diff-posn 'C 'end region-num))
 237             (pat1 (nth 0 ediff-combination-pattern))
 238             (pat2 (nth 1 ediff-combination-pattern))
 239             (pat3 (nth 2 ediff-combination-pattern))
 240             reg-a-beg reg-a-end reg-b-beg reg-b-end reg-c-beg reg-c-end)
 241
 242         (if combined
 243             (ediff-eval-in-buffer ediff-buffer-C
 244               (goto-char reg-beg)
 245               (search-forward pat1 reg-end 'noerror)
 246               (setq reg-a-beg (match-beginning 0))
 247               (setq reg-a-end (match-end 0))
 248               (search-forward pat2 reg-end 'noerror)
 249               (setq reg-b-beg (match-beginning 0))
 250               (setq reg-b-end (match-end 0))
 251               (search-forward pat3 reg-end 'noerror)
 252               (setq reg-c-beg (match-beginning 0))
 253               (setq reg-c-end (match-end 0))))
 254
 255         (if (and reg-a-beg reg-a-end reg-b-beg reg-b-end)
 256             (list reg-a-beg reg-a-end reg-b-beg reg-b-end reg-c-beg reg-c-end))
 257         )))
 258
 259
 260 (provide 'ediff-merg)
 261
 262 ;; ediff-merg.el ends here