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