diff-mode.el 42.8 KB
Newer Older
1 2
;;; diff-mode.el --- A mode for viewing/editing context diffs

3
;; Copyright (C) 1998, 1999, 2000  Free Software Foundation, Inc.
4 5 6

;; Author: Stefan Monnier <monnier@cs.yale.edu>
;; Keywords: patch diff
7
;; Revision: $Id: diff-mode.el,v 1.34 2000/11/12 16:59:52 monnier Exp $
8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42

;; This file is part of GNU Emacs.

;; GNU Emacs is free software; you can redistribute it and/or modify
;; it under the terms of the GNU General Public License as published by
;; the Free Software Foundation; either version 2, or (at your option)
;; any later version.

;; GNU Emacs is distributed in the hope that it will be useful,
;; but WITHOUT ANY WARRANTY; without even the implied warranty of
;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
;; GNU General Public License for more details.

;; You should have received a copy of the GNU General Public License
;; along with GNU Emacs; see the file COPYING.  If not, write to the
;; Free Software Foundation, Inc., 59 Temple Place - Suite 330,
;; Boston, MA 02111-1307, USA.

;;; Commentary:

;; Provides support for font-lock patterns, outline-regexps, navigation
;; commands, editing and various conversions as well as jumping
;; to the corresponding source file.

;; inspired by Pavel Machek's patch-mode.el (<pavel@atrey.karlin.mff.cuni.cz>)
;; some efforts were spent to have it somewhat compatible with XEmacs'
;; diff-mode as well as with compilation-minor-mode

;; to use it, simply add to your .emacs the following lines:
;; 
;; (autoload 'diff-mode "diff-mode" "Diff major mode" t)
;; (add-to-list 'auto-mode-alist '("\\.\\(diffs?\\|patch\\|rej\\)\\'" . diff-mode))

;; Bugs:

43
;; - Reverse doesn't work with normal diffs.
44 45 46

;; Todo:

47 48 49 50 51 52 53 54 55
;; - Improve narrowed-view support.
;; - Improve the `compile' support (?).
;; - Support for # comments in context->unified.
;; - Do a fuzzy search in diff-goto-source.
;; - Allow diff.el to use diff-mode.
;;   This mostly means ability to jump from half-hunk to half-hunk
;;   in context (and normal) diffs and to jump to the corresponding
;;   (i.e. new or old) file.
;; - Handle `diff -b' output in context->unified.
56

57 58 59 60
;; Low priority:
;; - Spice up the minor-mode with font-lock support.
;; - Recognize pcl-cvs' special string for `cvs-execute-single'.

61 62 63 64 65 66
;;; Code:

(eval-when-compile (require 'cl))


(defgroup diff-mode ()
67
  "Major mode for viewing/editing diffs"
68
  :version "21.1"
69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87
  :group 'tools
  :group 'diff)

(defcustom diff-jump-to-old-file-flag nil
  "*Non-nil means `diff-goto-source' jumps to the old file.
Else, it jumps to the new file."
  :group 'diff-mode
  :type '(boolean))

(defcustom diff-update-on-the-fly-flag t
  "*Non-nil means hunk headers are kept up-to-date on-the-fly.
When editing a diff file, the line numbers in the hunk headers
need to be kept consistent with the actual diff.  This can
either be done on the fly (but this sometimes interacts poorly with the
undo mechanism) or whenever the file is written (can be slow
when editing big diffs)."
  :group 'diff-mode
  :type '(boolean))

88 89 90 91 92 93
(defcustom diff-advance-after-apply-hunk t
  "*Non-nil means `diff-apply-hunk' will move to the next hunk after applying."
  :group 'diff-mode
  :type 'boolean)


94 95 96 97 98 99
(defvar diff-mode-hook nil
  "Run after setting up the `diff-mode' major mode.")

(defvar diff-outline-regexp
  "\\([*+][*+][*+] [^0-9]\\|@@ ...\\|\\*\\*\\* [0-9].\\|--- [0-9]..\\)")

100
;;;;
101
;;;; keymap, menu, ...
102
;;;;
103

104
(easy-mmode-defmap diff-mode-shared-map
105
  '(;; From Pavel Machek's patch-mode.
106 107 108 109 110 111
    ("n" . diff-hunk-next)
    ("N" . diff-file-next)
    ("p" . diff-hunk-prev)
    ("P" . diff-file-prev)
    ("k" . diff-hunk-kill)
    ("K" . diff-file-kill)
112
    ;; From compilation-minor-mode.
113 114
    ("}" . diff-file-next)
    ("{" . diff-file-prev)
115
    ("\C-m" . diff-goto-source)
116
    ([mouse-2] . diff-mouse-goto-source)
117
    ;; From XEmacs' diff-mode.
118 119 120 121 122 123 124 125 126 127 128
    ("W" . widen)
    ;;("." . diff-goto-source)		;display-buffer
    ;;("f" . diff-goto-source)		;find-file
    ("o" . diff-goto-source)		;other-window
    ;;("w" . diff-goto-source)		;other-frame
    ;;("N" . diff-narrow)
    ;;("h" . diff-show-header)
    ;;("j" . diff-show-difference)	;jump to Nth diff
    ;;("q" . diff-quit)
    (" " . scroll-up)
    ("\177" . scroll-down)
129
    ;; Our very own bindings.
130 131 132 133 134
    ("A" . diff-ediff-patch)
    ("r" . diff-restrict-view)
    ("R" . diff-reverse-direction)
    ("U" . diff-context->unified)
    ("C" . diff-unified->context))
135
  "Basic keymap for `diff-mode', bound to various prefix keys.")
136

137
(easy-mmode-defmap diff-mode-map
138
  `(("\e" . ,diff-mode-shared-map)
139 140 141
    ;; From compilation-minor-mode.
    ("\C-c\C-c" . diff-goto-source)
    ;; Misc operations.
142
    ("\C-c\C-s" . diff-split-hunk)
143 144
    ("\C-c\C-a" . diff-apply-hunk)
    ("\C-c\C-t" . diff-test-hunk))
145 146 147 148 149 150
  "Keymap for `diff-mode'.  See also `diff-mode-shared-map'.")

(easy-menu-define diff-mode-menu diff-mode-map
  "Menu for `diff-mode'."
  '("Diff"
    ["Jump to Source"		diff-goto-source	t]
151 152
    ["Apply hunk"		diff-apply-hunk		t]
    ["Apply diff with Ediff"	diff-ediff-patch	t]
153 154 155 156 157 158 159
    ["-----" nil nil]
    ["Reverse direction"	diff-reverse-direction	t]
    ["Context -> Unified"	diff-context->unified	t]
    ["Unified -> Context"	diff-unified->context	t]
    ;;["Fixup Headers"		diff-fixup-modifs	(not buffer-read-only)]
    ))

160
(defcustom diff-minor-mode-prefix "\C-c="
161 162
  "Prefix key for `diff-minor-mode' commands."
  :group 'diff-mode
163
  :type '(choice (string "\e") (string "C-c=") string))
164

165 166
(easy-mmode-defmap diff-minor-mode-map
  `((,diff-minor-mode-prefix . ,diff-mode-shared-map))
167 168
  "Keymap for `diff-minor-mode'.  See also `diff-mode-shared-map'.")

169

170
;;;;
171
;;;; font-lock support
172
;;;;
173

Stefan Monnier's avatar
Stefan Monnier committed
174
(defface diff-header-face
175
  '((((type tty pc) (class color) (background light))
176
     (:foreground "blue1" :bold t))
177
    (((type tty pc) (class color) (background dark))
178
     (:foreground "green" :bold t))
179
    (((class color) (background light))
180
     (:background "grey85"))
181 182
    (((class color) (background dark))
     (:background "grey45"))
183
    (t (:bold t)))
184
  "`diff-mode' face inherited by hunk and index header faces."
Stefan Monnier's avatar
Stefan Monnier committed
185 186 187
  :group 'diff-mode)
(defvar diff-header-face 'diff-header-face)

188
(defface diff-file-header-face
189
  '((((type tty pc) (class color) (background light))
190
     (:foreground "yellow" :bold t))
191
    (((type tty pc) (class color) (background dark))
192
     (:foreground "cyan" :bold t))
193
    (((class color) (background light))
194
     (:background "grey70" :bold t))
195 196
    (((class color) (background dark))
     (:background "grey60" :bold t))
197
    (t (:bold t)))			; :height 1.3
Stefan Monnier's avatar
Stefan Monnier committed
198
  "`diff-mode' face used to highlight file header lines."
199 200 201 202
  :group 'diff-mode)
(defvar diff-file-header-face 'diff-file-header-face)

(defface diff-index-face
Stefan Monnier's avatar
Stefan Monnier committed
203 204
  '((t (:inherit diff-file-header-face)))
  "`diff-mode' face used to highlight index header lines."
205 206 207 208
  :group 'diff-mode)
(defvar diff-index-face 'diff-index-face)

(defface diff-hunk-header-face
Stefan Monnier's avatar
Stefan Monnier committed
209 210
  '((t (:inherit diff-header-face)))
  "`diff-mode' face used to highlight hunk header lines."
211 212 213 214
  :group 'diff-mode)
(defvar diff-hunk-header-face 'diff-hunk-header-face)

(defface diff-removed-face
Stefan Monnier's avatar
Stefan Monnier committed
215 216
  '((t (:inherit diff-changed-face)))
  "`diff-mode' face used to highlight removed lines."
217 218 219 220
  :group 'diff-mode)
(defvar diff-removed-face 'diff-removed-face)

(defface diff-added-face
Stefan Monnier's avatar
Stefan Monnier committed
221 222
  '((t (:inherit diff-changed-face)))
  "`diff-mode' face used to highlight added lines."
223 224 225 226
  :group 'diff-mode)
(defvar diff-added-face 'diff-added-face)

(defface diff-changed-face
227
  '((((type tty pc) (class color) (background light))
228
     (:foreground "magenta" :bold t :italic t))
229
    (((type tty pc) (class color) (background dark))
230
     (:foreground "yellow" :bold t :italic t))
231
    (t ()))
Stefan Monnier's avatar
Stefan Monnier committed
232
  "`diff-mode' face used to highlight changed lines."
233 234 235
  :group 'diff-mode)
(defvar diff-changed-face 'diff-changed-face)

236 237 238 239 240 241
(defface diff-function-face
  '((t (:inherit diff-context-face)))
  "`diff-mode' face used to highlight function names produced by \"diff -p\"."
  :group 'diff-mode)
(defvar diff-function-face 'diff-function-face)

242 243 244 245 246 247
(defface diff-context-face
  '((((class color) (background light))
     (:foreground "grey50"))
    (((class color) (background dark))
     (:foreground "grey70"))
    (t ))
Stefan Monnier's avatar
Stefan Monnier committed
248 249
  "`diff-mode' face used to highlight context and other side-information."
  :group 'diff-mode)
250
(defvar diff-context-face 'diff-context-face)
Stefan Monnier's avatar
Stefan Monnier committed
251

252
(defvar diff-font-lock-keywords
Stefan Monnier's avatar
Stefan Monnier committed
253
  '(("^\\(@@ -[0-9,]+ \\+[0-9,]+ @@\\)\\(.*\\)$" ;unified
254
     (1 diff-hunk-header-face)
255
     (2 diff-function-face))
Stefan Monnier's avatar
Stefan Monnier committed
256 257 258
    ("^--- .+ ----$"		;context
     . diff-hunk-header-face)
    ("\\(\\*\\{15\\}\\)\\(.*\\)$"	;context
259
     (1 diff-hunk-header-face)
260
     (2 diff-function-face))
261
    ("^\\*\\*\\* .+ \\*\\*\\*\\*". diff-hunk-header-face) ;context
262
    ("^\\(---\\|\\+\\+\\+\\|\\*\\*\\*\\) \\(\\S-+\\)\\(.*[^*-]\\)?\n"
Stefan Monnier's avatar
Stefan Monnier committed
263
     (0 diff-header-face) (2 diff-file-header-face prepend))
264 265 266 267
    ("^[0-9,]+[acd][0-9,]+$" . diff-hunk-header-face)
    ("^!.*\n" . diff-changed-face)	;context
    ("^[+>].*\n" . diff-added-face)
    ("^[-<].*\n" . diff-removed-face)
Stefan Monnier's avatar
Stefan Monnier committed
268
    ("^Index: \\(.+\\).*\n" (0 diff-header-face) (1 diff-index-face prepend))
269
    ("^#.*" . font-lock-string-face)
270
    ("^[^-=+*!<>].*\n" . diff-context-face)))
271 272

(defconst diff-font-lock-defaults
273
  '(diff-font-lock-keywords t nil nil nil (font-lock-multiline . nil)))
274

275 276
(defvar diff-imenu-generic-expression
  ;; Prefer second name as first is most likely to be a backup or
277 278 279
  ;; version-control name.  The [\t\n] at the end of the unidiff pattern
  ;; catches Debian source diff files (which lack the trailing date).
  '((nil "\\+\\+\\+\\ \\([^\t\n]+\\)[\t\n]" 1) ; unidiffs
280 281
    (nil "^--- \\([^\t\n]+\\)\t.*\n\\*" 1))) ; context diffs

282 283 284 285 286 287 288 289 290 291 292 293
;;;;
;;;; Compile support
;;;;

(defvar diff-file-regexp-alist
  '(("Index: \\(.+\\)" 1)))

(defvar diff-error-regexp-alist
  '(("@@ -\\([0-9]+\\),[0-9]+ \\+\\([0-9]+\\),[0-9]+ @@" nil 2)
    ("--- \\([0-9]+\\),[0-9]+ ----" nil 1)
    ("\\([0-9]+\\)\\(,[0-9]+\\)?[adc]\\([0-9]+\\)" nil 3)))

294
;;;;
295
;;;; Movement
296
;;;;
297

298
(defconst diff-hunk-header-re "^\\(@@ -[0-9,]+ \\+[0-9,]+ @@.*\\|\\*\\{15\\}.*\n\\*\\*\\* .+ \\*\\*\\*\\*\\|[0-9]+\\(,[0-9]+\\)?[acd][0-9]+\\(,[0-9]+\\)?\\)$")
299 300 301 302 303
(defconst diff-file-header-re (concat "^\\(--- .+\n\\+\\+\\+\\|\\*\\*\\* .+\n---\\|[^-+!<>0-9@* ]\\).+\n" (substring diff-hunk-header-re 1)))
(defvar diff-narrowed-to nil)

(defun diff-end-of-hunk (&optional style)
  (if (looking-at diff-hunk-header-re) (goto-char (match-end 0)))
304 305 306 307 308 309 310 311 312
  (let ((end (and (re-search-forward (case style
				       (unified "^[^-+# \\]")
				       (context "^[^-+#! \\]")
				       (normal "^[^<>#\\]")
				       (t "^[^-+#!<> \\]"))
				     nil t)
		  (match-beginning 0))))
    ;; The return value is used by easy-mmode-define-navigation.
    (goto-char (or end (point-max)))))
313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330

(defun diff-beginning-of-hunk ()
  (beginning-of-line)
  (unless (looking-at diff-hunk-header-re)
    (forward-line 1)
    (condition-case ()
	(re-search-backward diff-hunk-header-re)
      (error (error "Can't find the beginning of the hunk")))))

(defun diff-beginning-of-file ()
  (beginning-of-line)
  (unless (looking-at diff-file-header-re)
    (forward-line 2)
    (condition-case ()
	(re-search-backward diff-file-header-re)
      (error (error "Can't find the beginning of the file")))))

(defun diff-end-of-file ()
331 332
  (re-search-forward "^[-+#!<>0-9@* \\]" nil t)
  (re-search-forward "^[^-+#!<>0-9@* \\]" nil 'move)
333 334
  (beginning-of-line))

335 336 337 338 339
;; Define diff-{hunk,file}-{prev,next}
(easy-mmode-define-navigation
 diff-hunk diff-hunk-header-re "hunk" diff-end-of-hunk)
(easy-mmode-define-navigation
 diff-file diff-file-header-re "file" diff-end-of-hunk)
340 341 342 343 344 345 346 347 348 349 350 351 352

(defun diff-restrict-view (&optional arg)
  "Restrict the view to the current hunk.
If the prefix ARG is given, restrict the view to the current file instead."
  (interactive "P")
  (save-excursion
    (if arg (diff-beginning-of-file) (diff-beginning-of-hunk))
    (narrow-to-region (point)
		      (progn (if arg (diff-end-of-file) (diff-end-of-hunk))
			     (point)))
    (set (make-local-variable 'diff-narrowed-to) (if arg 'file 'hunk))))


353
(defun diff-hunk-kill ()
354 355 356 357 358 359
  "Kill current hunk."
  (interactive)
  (diff-beginning-of-hunk)
  (let ((start (point))
	(firsthunk (save-excursion
		     (ignore-errors
360
		       (diff-beginning-of-file) (diff-hunk-next) (point))))
361 362
	(nexthunk  (save-excursion
		     (ignore-errors
363
		       (diff-hunk-next) (point))))
364 365
	(nextfile (save-excursion
		    (ignore-errors
366
		      (diff-file-next) (point)))))
367 368 369 370
    (if (and firsthunk (= firsthunk start)
	     (or (null nexthunk)
		 (and nextfile (> nexthunk nextfile))))
	;; we're the only hunk for this file, so kill the file
371
	(diff-file-kill)
372 373 374
      (diff-end-of-hunk)
      (kill-region start (point)))))

375
(defun diff-file-kill ()
376 377 378 379 380 381
  "Kill current file's hunks."
  (interactive)
  (diff-beginning-of-file)
  (let* ((start (point))
	 (prevhunk (save-excursion
		     (ignore-errors
382
		       (diff-hunk-prev) (point))))
383 384 385 386 387 388
	 (index (save-excursion
		  (re-search-backward "^Index: " prevhunk t))))
    (when index (setq start index))
    (diff-end-of-file)
    (kill-region start (point))))

389 390 391 392 393 394 395 396 397 398 399 400 401 402 403
(defun diff-kill-junk ()
  "Kill spurious empty diffs."
  (interactive)
  (save-excursion
    (let ((inhibit-read-only t))
      (goto-char (point-min))
      (while (re-search-forward (concat "^\\(Index: .*\n\\)"
					"\\([^-+!* <>].*\n\\)*?"
					"\\(\\(Index:\\) \\|"
					diff-file-header-re "\\)")
				nil t)
	(delete-region (if (match-end 4) (match-beginning 0) (match-end 1))
		       (match-beginning 3))
	(beginning-of-line)))))

404 405 406 407 408 409 410 411 412 413 414 415 416 417 418 419 420 421 422 423 424 425 426 427 428 429 430 431
(defun diff-count-matches (re start end)
  (save-excursion
    (let ((n 0))
      (goto-char start)
      (while (re-search-forward re end t) (incf n))
      n)))

(defun diff-split-hunk ()
  "Split the current (unified diff) hunk at point into two hunks."
  (interactive)
  (beginning-of-line)
  (let ((pos (point))
	(start (progn (diff-beginning-of-hunk) (point))))
    (unless (looking-at "@@ -\\([0-9]+\\),[0-9]+ \\+\\([0-9]+\\),[0-9]+ @@")
      (error "diff-split-hunk only works on unified context diffs"))
    (forward-line 1)
    (let* ((start1 (string-to-number (match-string 1)))
	   (start2 (string-to-number (match-string 2)))
	   (newstart1 (+ start1 (diff-count-matches "^[- \t]" (point) pos)))
	   (newstart2 (+ start2 (diff-count-matches "^[+ \t]" (point) pos))))
      (goto-char pos)
      ;; Hopefully the after-change-function will not screw us over.
      (insert "@@ -" (number-to-string newstart1) ",1 +"
	      (number-to-string newstart2) ",1 @@\n")
      ;; Fix the original hunk-header.
      (diff-fixup-modifs start pos))))
      

432 433 434 435
;;;;
;;;; jump to other buffers
;;;;

436 437
(defvar diff-remembered-files-alist nil)

438 439 440
(defun diff-filename-drop-dir (file)
  (when (string-match "/" file) (substring file (match-end 0))))

441 442 443
(defun diff-merge-strings (ancestor from to)
  "Merge the diff between ANCESTOR and FROM into TO.
Returns the merged string if successful or nil otherwise.
444
The strings are assumed not to contain any \"\\n\" (i.e. end of line).
445 446 447 448 449 450 451 452
If ANCESTOR = FROM, returns TO.
If ANCESTOR = TO, returns FROM.
The heuristic is simplistic and only really works for cases
like \(diff-merge-strings \"b/foo\" \"b/bar\" \"/a/c/foo\")."
  ;; Ideally, we want:
  ;;   AMB ANB CMD -> CND
  ;; but that's ambiguous if `foo' or `bar' is empty:
  ;; a/foo a/foo1 b/foo.c -> b/foo1.c but not 1b/foo.c or b/foo.c1
453
  (let ((str (concat ancestor "\n" from "\n" to)))
454
    (when (and (string-match (concat
455 456
			      "\\`\\(.*?\\)\\(.*\\)\\(.*\\)\n"
			      "\\1\\(.*\\)\\3\n"
457 458 459 460 461 462
			      "\\(.*\\(\\2\\).*\\)\\'") str)
	       (equal to (match-string 5 str)))
      (concat (substring str (match-beginning 5) (match-beginning 6))
	      (match-string 4 str)
	      (substring str (match-end 6) (match-end 5))))))

463 464 465 466 467 468 469 470 471
(defun diff-find-file-name (&optional old)
  "Return the file corresponding to the current patch.
Non-nil OLD means that we want the old file."
  (save-excursion
    (unless (looking-at diff-file-header-re)
      (or (ignore-errors (diff-beginning-of-file))
	  (re-search-forward diff-file-header-re nil t)))
    (let* ((limit (save-excursion
		   (condition-case ()
472
		       (progn (diff-hunk-prev) (point))
473
		     (error (point-min)))))
474
	   (header-files
475
	    (if (looking-at "[-*][-*][-*] \\(\\S-+\\)\\(\\s-.*\\)?\n[-+][-+][-+] \\(\\S-+\\)")
476 477
		(list (if old (match-string 1) (match-string 3))
		      (if old (match-string 3) (match-string 1)))
478
	      (forward-line 1) nil))
479 480 481 482
	   (fs (append
		(when (save-excursion
			(re-search-backward "^Index: \\(.+\\)" limit t))
		  (list (match-string 1)))
483
		header-files
484 485 486
		(when (re-search-backward "^diff \\(-\\S-+ +\\)*\\(\\S-+\\)\\( +\\(\\S-+\\)\\)?" nil t)
		  (list (if old (match-string 2) (match-string 4))
			(if old (match-string 4) (match-string 2))))))
487
	   (fs (delq nil fs)))
488
      (or
489 490 491 492 493 494 495 496 497 498 499 500 501 502 503 504 505
       ;; use any previously used preference
       (cdr (assoc fs diff-remembered-files-alist))
       ;; try to be clever and use previous choices as an inspiration
       (dolist (rf diff-remembered-files-alist)
	 (let ((newfile (diff-merge-strings (caar rf) (car fs) (cdr rf))))
	   (if (and newfile (file-exists-p newfile)) (return newfile))))
       ;; look for each file in turn.  If none found, try again but
       ;; ignoring the first level of directory, ...
       (do* ((files fs (delq nil (mapcar 'diff-filename-drop-dir files)))
	     (file nil nil))
	   ((or (null files)
		(setq file (do* ((files files (cdr files))
				 (file (car files) (car files)))
			       ((or (null file) (file-exists-p file))
				file))))
	    file))
       ;; <foo>.rej patches implicitly apply to <foo>
506 507 508
       (and (string-match "\\.rej\\'" (or buffer-file-name ""))
	    (let ((file (substring buffer-file-name 0 (match-beginning 0))))
	      (when (file-exists-p file) file)))
509 510 511 512 513
       ;; if all else fails, ask the user
       (let ((file (read-file-name (format "Use file %s: " (or (first fs) ""))
				   nil (first fs) t (first fs))))
	 (set (make-local-variable 'diff-remembered-files-alist)
	      (cons (cons fs file) diff-remembered-files-alist))
514 515
	 file)))))

516

517 518 519 520 521 522
(defun diff-mouse-goto-source (event)
  "Run `diff-goto-source' for the diff at a mouse click."
  (interactive "e")
  (save-excursion
    (mouse-set-point event)
    (diff-goto-source)))
523

524

525 526 527 528
(defun diff-ediff-patch ()
  "Call `ediff-patch-file' on the current buffer."
  (interactive)
  (condition-case err
529
      (ediff-patch-file nil (current-buffer))
530 531 532 533 534 535 536 537 538 539 540 541 542 543 544 545 546 547 548 549 550
    (wrong-number-of-arguments (ediff-patch-file))))

;;;; 
;;;; Conversion functions
;;;; 

;;(defvar diff-inhibit-after-change nil
;;  "Non-nil means inhibit `diff-mode's after-change functions.")

(defun diff-unified->context (start end)
  "Convert unified diffs to context diffs.
START and END are either taken from the region (if a prefix arg is given) or
else cover the whole bufer."
  (interactive (if current-prefix-arg
		   (list (mark) (point))
		 (list (point-min) (point-max))))
  (unless (markerp end) (setq end (copy-marker end)))
  (let (;;(diff-inhibit-after-change t)
	(inhibit-read-only t))
    (save-excursion
      (goto-char start)
551
      (while (and (re-search-forward "^\\(\\(---\\) .+\n\\(\\+\\+\\+\\) .+\\|@@ -\\([0-9]+\\),\\([0-9]+\\) \\+\\([0-9]+\\),\\([0-9]+\\) @@.*\\)$" nil t)
552 553 554
		  (< (point) end))
	(combine-after-change-calls
	  (if (match-beginning 2)
555
	      ;; we matched a file header
556 557 558 559 560 561 562 563 564 565 566 567 568 569 570 571 572 573 574 575 576 577 578 579 580 581 582 583 584 585 586 587 588 589 590 591 592 593 594 595 596 597 598 599 600 601 602 603 604 605 606 607 608 609 610 611 612 613 614 615 616 617 618 619 620 621 622 623 624 625 626 627 628 629 630 631 632 633 634 635 636 637
	      (progn
		;; use reverse order to make sure the indices are kept valid
		(replace-match "---" t t nil 3)
		(replace-match "***" t t nil 2))
	    ;; we matched a hunk header
	    (let ((line1 (match-string 4))
		  (lines1 (match-string 5))
		  (line2 (match-string 6))
		  (lines2 (match-string 7)))
	      (replace-match
	       (concat "***************\n*** " line1 ","
		       (number-to-string (+ (string-to-number line1)
					    (string-to-number lines1)
					    -1)) " ****"))
	      (forward-line 1)
	      (save-restriction
		(narrow-to-region (point)
				  (progn (diff-end-of-hunk 'unified) (point)))
		(let ((hunk (buffer-string)))
		  (goto-char (point-min))
		  (if (not (save-excursion (re-search-forward "^-" nil t)))
		      (delete-region (point) (point-max))
		    (goto-char (point-max))
		    (let ((modif nil) last-pt)
		      (while (progn (setq last-pt (point))
				    (= (forward-line -1) 0))
			(case (char-after)
			  (?  (insert " ") (setq modif nil) (backward-char 1))
			  (?+ (delete-region (point) last-pt) (setq modif t))
			  (?- (if (not modif)
				  (progn (forward-char 1)
					 (insert " "))
				(delete-char 1)
				(insert "! "))
			      (backward-char 2))
			  (?\\ (when (save-excursion (forward-line -1)
						     (= (char-after) ?+))
				 (delete-region (point) last-pt) (setq modif t)))
			  (t (setq modif nil))))))
		  (goto-char (point-max))
		  (save-excursion
		    (insert "--- " line2 ","
			    (number-to-string (+ (string-to-number line2)
						 (string-to-number lines2)
						 -1)) " ----\n" hunk))
		  ;;(goto-char (point-min))
		  (forward-line 1)
		  (if (not (save-excursion (re-search-forward "^+" nil t)))
		      (delete-region (point) (point-max))
		    (let ((modif nil) (delete nil))
		      (while (not (eobp))
			(case (char-after)
			  (?  (insert " ") (setq modif nil) (backward-char 1))
			  (?- (setq delete t) (setq modif t))
			  (?+ (if (not modif)
				  (progn (forward-char 1)
					 (insert " "))
				(delete-char 1)
				(insert "! "))
			      (backward-char 2))
			  (?\\ (when (save-excursion (forward-line 1)
						     (not (eobp)))
				 (setq delete t) (setq modif t)))
			  (t (setq modif nil)))
			(let ((last-pt (point)))
			  (forward-line 1)
			  (when delete
			    (delete-region last-pt (point))
			    (setq delete nil)))))))))))))))

(defun diff-context->unified (start end)
  "Convert context diffs to unified diffs.
START and END are either taken from the region (if a prefix arg is given) or
else cover the whole bufer."
  (interactive (if current-prefix-arg
		   (list (mark) (point))
		 (list (point-min) (point-max))))
  (unless (markerp end) (setq end (copy-marker end)))
  (let (;;(diff-inhibit-after-change t)
	(inhibit-read-only t))
    (save-excursion
      (goto-char start)
638
      (while (and (re-search-forward "^\\(\\(\\*\\*\\*\\) .+\n\\(---\\) .+\\|\\*\\{15\\}.*\n\\*\\*\\* \\([0-9]+\\),\\(-?[0-9]+\\) \\*\\*\\*\\*\\)$" nil t)
639 640 641 642 643 644 645 646 647 648 649 650 651 652 653 654 655 656 657 658 659 660 661 662 663 664 665 666 667 668 669 670 671 672 673 674 675 676 677 678 679 680 681 682 683 684 685 686 687 688 689 690 691 692 693 694 695 696 697 698 699 700 701 702 703 704 705 706 707 708 709
		  (< (point) end))
	(combine-after-change-calls
	  (if (match-beginning 2)
	      ;; we matched a file header
	      (progn
		;; use reverse order to make sure the indices are kept valid
		(replace-match "+++" t t nil 3)
		(replace-match "---" t t nil 2))
	    ;; we matched a hunk header
	    (let ((line1s (match-string 4))
		  (line1e (match-string 5))
		  (pt1 (match-beginning 0)))
	      (replace-match "")
	      (unless (re-search-forward
		       "^--- \\([0-9]+\\),\\(-?[0-9]+\\) ----$" nil t)
		(error "Can't find matching `--- n1,n2 ----' line"))
	      (let ((line2s (match-string 1))
		    (line2e (match-string 2))
		    (pt2 (progn
			   (delete-region (progn (beginning-of-line) (point))
					  (progn (forward-line 1) (point)))
			   (point-marker))))
		(goto-char pt1)
		(forward-line 1)
		(while (< (point) pt2)
		  (case (char-after)
		    ((?! ?-) (delete-char 2) (insert "-") (forward-line 1))
		    (?\ 		;merge with the other half of the chunk
		     (let* ((endline2
			     (save-excursion
			       (goto-char pt2) (forward-line 1) (point)))
			    (c (char-after pt2)))
		       (case c
			 ((?! ?+)
			  (insert "+"
				  (prog1 (buffer-substring (+ pt2 2) endline2)
				    (delete-region pt2 endline2))))
			 (?\ 		;FIXME: check consistency
			  (delete-region pt2 endline2)
			  (delete-char 1)
			  (forward-line 1))
			 (?\\ (forward-line 1))
			 (t (delete-char 1) (forward-line 1)))))
		    (t (forward-line 1))))
		(while (looking-at "[+! ] ")
		  (if (/= (char-after) ?!) (forward-char 1)
		    (delete-char 1) (insert "+"))
		  (delete-char 1) (forward-line 1))
		(save-excursion
		  (goto-char pt1)
		  (insert "@@ -" line1s ","
			  (number-to-string (- (string-to-number line1e)
					       (string-to-number line1s)
					       -1))
			  " +" line2s ","
			  (number-to-string (- (string-to-number line2e)
					       (string-to-number line2s)
					       -1)) " @@"))))))))))

(defun diff-reverse-direction (start end)
  "Reverse the direction of the diffs.
START and END are either taken from the region (if a prefix arg is given) or
else cover the whole bufer."
  (interactive (if current-prefix-arg
		   (list (mark) (point))
		 (list (point-min) (point-max))))
  (unless (markerp end) (setq end (copy-marker end)))
  (let (;;(diff-inhibit-after-change t)
	(inhibit-read-only t))
    (save-excursion
      (goto-char start)
710
      (while (and (re-search-forward "^\\(\\([-*][-*][-*] \\)\\(.+\\)\n\\([-+][-+][-+] \\)\\(.+\\)\\|\\*\\{15\\}.*\n\\*\\*\\* \\(.+\\) \\*\\*\\*\\*\\|@@ -\\([0-9,]+\\) \\+\\([0-9,]+\\) @@.*\\)$" nil t)
711 712 713 714 715 716 717 718 719 720 721 722
		  (< (point) end))
	(combine-after-change-calls
	  (cond
	   ;; a file header
	   ((match-beginning 2) (replace-match "\\2\\5\n\\4\\3" nil))
	   ;; a context-diff hunk header
	   ((match-beginning 6)
	    (let ((pt-lines1 (match-beginning 6))
		  (lines1 (match-string 6)))
	      (replace-match "" nil nil nil 6)
	      (forward-line 1)
	      (let ((half1s (point)))
723
		(while (looking-at "[-! \\][ \t]\\|#")
724 725
		  (when (= (char-after) ?-) (delete-char 1) (insert "+"))
		  (forward-line 1))
726
		(let ((half1 (delete-and-extract-region half1s (point))))
727 728 729 730 731 732 733
		  (unless (looking-at "^--- \\([0-9]+,-?[0-9]+\\) ----$")
		    (insert half1)
		    (error "Can't find matching `--- n1,n2 ----' line"))
		  (let ((str1 (match-string 1)))
		    (replace-match lines1 nil nil nil 1)
		    (forward-line 1)
		    (let ((half2s (point)))
734
		      (while (looking-at "[!+ \\][ \t]\\|#")
735 736
			(when (= (char-after) ?+) (delete-char 1) (insert "-"))
			(forward-line 1))
737
		      (let ((half2 (delete-and-extract-region half2s (point))))
738
			(insert (or half1 ""))
739
			(goto-char half1s)
740
			(insert (or half2 ""))))
741 742 743 744 745 746 747 748 749 750 751 752
		    (goto-char pt-lines1)
		    (insert str1))))))
	   ;; a unified-diff hunk header
	   ((match-beginning 7)
	    (replace-match "@@ -\\8 +\\7 @@" nil)
	    (forward-line 1)
	    (let ((c (char-after)) first last)
	      (while (case (setq c (char-after))
		       (?- (setq first (or first (point)))
			   (delete-char 1) (insert "+") t)
		       (?+ (setq last (or last (point)))
			   (delete-char 1) (insert "-") t)
753
		       ((?\\ ?#) t)
754
		       (t (when (and first last (< first last))
755 756 757
			    (let ((str
				   (save-excursion
				     (delete-and-extract-region first last))))
758 759 760 761 762 763 764 765 766 767 768 769 770 771 772 773 774
			      (insert str)))
			  (setq first nil last nil)
			  (equal ?\  c)))
		(forward-line 1))))))))))

(defun diff-fixup-modifs (start end)
  "Fixup the hunk headers (in case the buffer was modified).
START and END are either taken from the region (if a prefix arg is given) or
else cover the whole bufer."
  (interactive (if current-prefix-arg
		   (list (mark) (point))
		 (list (point-min) (point-max))))
  (let ((inhibit-read-only t))
    (save-excursion
      (goto-char end) (diff-end-of-hunk)
      (let ((plus 0) (minus 0) (space 0) (bang 0))
	(while (and (= (forward-line -1) 0) (<= start (point)))
775
	  (if (not (looking-at "\\(@@ -[0-9,]+ \\+[0-9,]+ @@.*\\|[-*][-*][-*] .+ [-*][-*][-*][-*]\\)$"))
776 777 778 779 780
	      (case (char-after)
		(?\  (incf space))
		(?+ (incf plus))
		(?- (incf minus))
		(?! (incf bang))
781
		((?\\ ?#) nil)
782 783
		(t  (setq space 0 plus 0 minus 0 bang 0)))
	    (cond
784
	     ((looking-at "@@ -[0-9]+,\\([0-9]*\\) \\+[0-9]+,\\([0-9]*\\) @@.*$")
785 786 787 788 789 790 791 792 793 794 795 796 797 798 799 800 801 802 803 804 805 806 807 808 809 810 811 812 813 814 815 816 817 818 819 820 821 822
	      (let* ((old1 (match-string 1))
		     (old2 (match-string 2))
		     (new1 (number-to-string (+ space minus)))
		     (new2 (number-to-string (+ space plus))))
		(unless (string= new2 old2) (replace-match new2 t t nil 2))
		(unless (string= new1 old1) (replace-match new1 t t nil 1))))
	     ((looking-at "--- \\([0-9]+\\),\\([0-9]*\\) ----$")
	      (when (> (+ space bang plus) 0)
		(let* ((old1 (match-string 1))
		       (old2 (match-string 2))
		       (new (number-to-string
			     (+ space bang plus -1 (string-to-number old1)))))
		  (unless (string= new old2) (replace-match new t t nil 2)))))
	     ((looking-at "\\*\\*\\* \\([0-9]+\\),\\(-?[0-9]*\\) \\*\\*\\*\\*$")
	      (when (> (+ space bang minus) 0)
		(let* ((old (match-string 1))
		       (new (format
			     (concat "%0" (number-to-string (length old)) "d")
			     (+ space bang minus -1 (string-to-number old)))))
		  (unless (string= new old) (replace-match new t t nil 2))))))
	    (setq space 0 plus 0 minus 0 bang 0)))))))

;;;; 
;;;; Hooks
;;;; 

(defun diff-write-contents-hooks ()
  "Fixup hunk headers if necessary."
  (if (buffer-modified-p) (diff-fixup-modifs (point-min) (point-max)))
  nil)

;; It turns out that making changes in the buffer from within an
;; *-change-function is asking for trouble, whereas making them
;; from a post-command-hook doesn't pose much problems
(defvar diff-unhandled-changes nil)
(defun diff-after-change-function (beg end len)
  "Remember to fixup the hunk header.
See `after-change-functions' for the meaning of BEG, END and LEN."
823 824 825 826 827
  ;; Ignoring changes when inhibit-read-only is set is strictly speaking
  ;; incorrect, but it turns out that inhibit-read-only is normally not set
  ;; inside editing commands, while it tends to be set when the buffer gets
  ;; updated by an async process or by a conversion function, both of which
  ;; would rather not be uselessly slowed down by this hook.
828 829 830 831 832 833 834 835 836 837 838 839
  (when (and (not undo-in-progress) (not inhibit-read-only))
    (if diff-unhandled-changes
	(setq diff-unhandled-changes
	      (cons (min beg (car diff-unhandled-changes))
		    (max beg (cdr diff-unhandled-changes))))
      (setq diff-unhandled-changes (cons beg end)))))

(defun diff-post-command-hook ()
  "Fixup hunk headers if necessary."
  (when (consp diff-unhandled-changes)
    (ignore-errors
      (save-excursion
840 841 842 843 844 845 846 847 848
	(goto-char (car diff-unhandled-changes))
	(unless (ignore-errors
		  (diff-beginning-of-hunk)
		  (save-excursion
		    (diff-end-of-hunk)
		    (> (point) (car diff-unhandled-changes))))
	  (goto-char (car diff-unhandled-changes))
	  (re-search-forward diff-hunk-header-re (cdr diff-unhandled-changes))
	  (diff-beginning-of-hunk))
849 850 851 852 853 854 855 856
	(diff-fixup-modifs (point) (cdr diff-unhandled-changes))))
    (setq diff-unhandled-changes nil)))

;;;; 
;;;; The main function
;;;; 

;;;###autoload
857
(define-derived-mode diff-mode fundamental-mode "Diff"
858
  "Major mode for viewing/editing context diffs.
859 860 861 862 863 864
Supports unified and context diffs as well as (to a lesser extent) normal diffs.
When the buffer is read-only, the ESC prefix is not necessary.
This mode runs `diff-mode-hook'.
\\{diff-mode-map}"
  (set (make-local-variable 'font-lock-defaults) diff-font-lock-defaults)
  (set (make-local-variable 'outline-regexp) diff-outline-regexp)
865 866
  (set (make-local-variable 'imenu-generic-expression)
       diff-imenu-generic-expression)
867 868 869 870 871 872 873 874 875 876
  ;; These are not perfect.  They would be better done separately for
  ;; context diffs and unidiffs.
  ;; (set (make-local-variable 'paragraph-start)
  ;;        (concat "@@ "			; unidiff hunk
  ;; 	       "\\|\\*\\*\\* "		; context diff hunk or file start
  ;; 	       "\\|--- [^\t]+\t"))	; context or unidiff file
  ;; 					; start (first or second line)
  ;;   (set (make-local-variable 'paragraph-separate) paragraph-start)
  ;;   (set (make-local-variable 'page-delimiter) "--- [^\t]+\t")
  ;; compile support
877 878 879 880 881 882 883 884
  (set (make-local-variable 'compilation-file-regexp-alist)
       diff-file-regexp-alist)
  (set (make-local-variable 'compilation-error-regexp-alist)
       diff-error-regexp-alist)
  (when (string-match "\\.rej\\'" (or buffer-file-name ""))
    (set (make-local-variable 'compilation-current-file)
	 (substring buffer-file-name 0 (match-beginning 0))))
  (compilation-shell-minor-mode 1)
885 886
  ;; setup change hooks
  (toggle-read-only t)
887 888 889
  (if (not diff-update-on-the-fly-flag)
      (add-hook 'write-contents-hooks 'diff-write-contents-hooks)
    (make-local-variable 'diff-unhandled-changes)
890 891
    (add-hook 'after-change-functions 'diff-after-change-function nil t)
    (add-hook 'post-command-hook 'diff-post-command-hook nil t))
892
  ;; Neat trick from Dave Love to add more bindings in read-only mode:
893
  (add-to-list (make-local-variable 'minor-mode-overriding-map-alist)
894 895 896 897
  	       (cons 'buffer-read-only diff-mode-shared-map))
  ;; add-log support
  (set (make-local-variable 'add-log-current-defun-function)
       'diff-current-defun)
898 899
  (set (make-local-variable 'add-log-buffer-file-name-function)
       'diff-find-file-name))
900 901

;;;###autoload
902 903 904 905 906
(define-minor-mode diff-minor-mode
  "Minor mode for viewing/editing context diffs.
\\{diff-minor-mode-map}"
  nil " Diff" nil
  ;; FIXME: setup font-lock
907 908 909 910
  ;; setup change hooks
  (if (not diff-update-on-the-fly-flag)
      (add-hook 'write-contents-hooks 'diff-write-contents-hooks)
    (make-local-variable 'diff-unhandled-changes)
911 912
    (add-hook 'after-change-functions 'diff-after-change-function nil t)
    (add-hook 'post-command-hook 'diff-post-command-hook nil t)))
913

914

915 916 917 918 919 920 921 922 923 924 925 926 927 928
;;;
;;; Misc operations that have proved useful at some point.
;;;

(defun diff-next-complex-hunk ()
  "Jump to the next \"complex\" hunk.
\"Complex\" is approximated by \"the hunk changes the number of lines\".
Only works for unified diffs."
  (interactive)
  (while
      (and (re-search-forward "^@@ [-0-9]+,\\([0-9]+\\) [+0-9]+,\\([0-9]+\\) @@"
			      nil t)
	   (equal (match-string 1) (match-string 2)))))

929
(defun diff-hunk-text (hunk destp &optional char-offset)
930
  "Return the literal source text from HUNK.
Stefan Monnier's avatar
Stefan Monnier committed
931
if DESTP is nil return the source, otherwise the destination text.
932
If CHAR-OFFSET is non-nil, it should be a char-offset in
Miles Bader's avatar
Miles Bader committed
933
HUNK, and instead of a string, a cons cell is returned whose car is the
934
appropriate text, and whose cdr is the corresponding char-offset in that text."
935
  (with-temp-buffer
936 937 938 939 940 941 942 943 944 945 946 947 948 949 950 951 952 953 954 955 956 957 958 959 960 961 962 963 964 965 966 967 968 969 970 971 972 973 974 975 976 977 978 979 980 981 982 983 984 985 986 987 988 989 990 991 992 993 994 995 996 997 998 999 1000 1001 1002 1003 1004 1005 1006 1007 1008 1009
    (insert hunk)
    (goto-char (point-min))
    (let ((src-pos nil)
	  (dst-pos nil)
	  (divider-pos nil)
	  (num-pfx-chars 2))
      ;; Set the following variables:
      ;;  SRC-POS     buffer pos of the source part of the hunk or nil if none
      ;;  DST-POS     buffer pos of the destination part of the hunk or nil
      ;;  DIVIDER-POS buffer pos of any divider line separating the src & dst
      ;;  NUM-PFX-CHARS  number of line-prefix characters used by this format"
      (cond ((looking-at "^@@")
	     ;; unified diff
	     (setq num-pfx-chars 1)
	     (forward-line 1)
	     (setq src-pos (point) dst-pos (point)))
	    ((looking-at "^\\*\\*")
	     ;; context diff
	     (forward-line 2)
	     (setq src-pos (point))
	     (re-search-forward "^--- " nil t)
	     (forward-line 0)
	     (setq divider-pos (point))
	     (forward-line 1)
	     (setq dst-pos (point)))
	    ((looking-at "^[0-9]+a[0-9,]+$")
	     ;; normal diff, insert
	     (forward-line 1)
	     (setq dst-pos (point)))
	    ((looking-at "^[0-9,]+d[0-9]+$")
	     ;; normal diff, delete
	     (forward-line 1)
	     (setq src-pos (point)))
	    ((looking-at "^[0-9,]+c[0-9,]+$")
	     ;; normal diff, change
	     (forward-line 1)
	     (setq src-pos (point))
	     (re-search-forward "^---$" nil t)
	     (forward-line 0)
	     (setq divider-pos (point))
	     (forward-line 1)
	     (setq dst-pos (point)))
	    (t
	     (error "Unknown diff hunk type")))

      (if (if destp (null dst-pos) (null src-pos))
	  ;; Implied empty text
	  (if char-offset '("" . 0) "")

	;; For context diffs, either side can be empty, (if there's only
	;; added or only removed text).  We should then use the other side.
	(cond ((equal src-pos divider-pos) (setq src-pos dst-pos))
	      ((equal dst-pos (point-max)) (setq dst-pos src-pos)))

	(when char-offset (goto-char (+ (point-min) char-offset)))

	;; Get rid of anything except the desired text.
	(save-excursion
	  ;; Delete unused text region
	  (let ((keep (if destp dst-pos src-pos)))
	    (when (and divider-pos (> divider-pos keep))
	      (delete-region divider-pos (point-max)))
	    (delete-region (point-min) keep))
	  ;; Remove line-prefix characters, and unneeded lines (unified diffs).
	  (let ((kill-char (if destp ?- ?+)))
	    (goto-char (point-min))
	    (while (not (eobp))
	      (if (eq (char-after) kill-char)
		  (delete-region (point) (progn (forward-line 1) (point)))
		(delete-char num-pfx-chars)
		(forward-line 1)))))

	(let ((text (buffer-substring-no-properties (point-min) (point-max))))
	  (if char-offset (cons text (- (point) (point-min))) text))))))
1010

1011

Stefan Monnier's avatar
Stefan Monnier committed
1012
(defun diff-find-text (text)
1013
  "Return the buffer position of the nearest occurrence of TEXT.
1014 1015 1016
If TEXT isn't found, nil is returned."
  (let* ((orig (point))
	 (forw (and (search-forward text nil t)
1017
			  (match-beginning 0)))
1018 1019
	 (back (and (goto-char (+ orig (length text)))
		    (search-backward text nil t)
1020 1021
			  (match-beginning 0))))
	  ;; Choose the closest match.
1022 1023 1024 1025
    (if (and forw back)
	(if (> (- forw orig) (- orig back)) back forw)
      (or back forw))))

1026 1027
(defsubst diff-xor (a b) (if a (not b) b))

Stefan Monnier's avatar
Stefan Monnier committed
1028
(defun diff-find-source-location (&optional other-file reverse)
1029
  "Find out (BUF LINE-OFFSET POS SRC DST SWITCHED)."
Stefan Monnier's avatar
Stefan Monnier committed
1030
  (save-excursion
1031 1032 1033 1034 1035 1036
    (let* ((other (diff-xor other-file diff-jump-to-old-file-flag))
	   (char-offset (- (point) (progn (diff-beginning-of-hunk) (point))))
	   (hunk (buffer-substring (point)
				   (save-excursion (diff-end-of-hunk) (point))))
	   (old (diff-hunk-text hunk reverse char-offset))
	   (new (diff-hunk-text hunk (not reverse) char-offset))
Stefan Monnier's avatar
Stefan Monnier committed
1037
	   ;; Find the location specification.
Stefan Monnier's avatar
Stefan Monnier committed
1038
	   (line (if (not (looking-at "\\(?:\\*\\{15\\}.*\n\\)?[-@* ]*\\([0-9,]+\\)\\([ acd+]+\\([0-9,]+\\)\\)?"))
1039 1040 1041 1042 1043 1044 1045 1046
		     (error "Can't find the hunk header")
		   (if other (match-string 1)
		     (if (match-end 3) (match-string 3)
		       (unless (re-search-forward "^--- \\([0-9,]+\\)" nil t)
			 (error "Can't find the hunk separator"))
		       (match-string 1)))))
	   (file (or (diff-find-file-name other) (error "Can't find the file")))
	   (buf (find-file-noselect file)))
Stefan Monnier's avatar
Stefan Monnier committed
1047 1048
      ;; Update the user preference if he so wished.
      (when (> (prefix-numeric-value other-file) 8)
1049
	(setq diff-jump-to-old-file-flag other))
Stefan Monnier's avatar
Stefan Monnier committed
1050 1051 1052 1053 1054 1055 1056
      (with-current-buffer buf
	(goto-line (string-to-number line))
	(let* ((orig-pos (point))
	       (pos (diff-find-text (car old)))
	       (switched nil))
	  (when (null pos)
	    (setq pos (diff-find-text (car new)) switched t))
1057 1058 1059 1060 1061
	  (nconc
	   (list buf)
	   (if pos (list (count-lines orig-pos pos) pos) (list nil orig-pos))
	   (if switched (list new old t) (list old new))))))))

Stefan Monnier's avatar
Stefan Monnier committed
1062

1063 1064 1065 1066 1067 1068 1069 1070 1071 1072 1073 1074
(defun diff-hunk-status-msg (line-offset reversed dry-run)
  (let ((msg (if dry-run
		 (if reversed "already applied" "not yet applied")
	       (if reversed "undone" "applied"))))
    (message (cond ((null line-offset) "Hunk text not found")
		   ((= line-offset 0) "Hunk %s")
		   ((= line-offset 1) "Hunk %s at offset %d line")
		   (t "Hunk %s at offset %d lines"))
	     msg line-offset)))


(defun diff-apply-hunk (&optional reverse)
1075
  "Apply the current hunk to the source file and go to the next.
1076 1077 1078 1079 1080
By default, the new source file is patched, but if the variable
`diff-jump-to-old-file-flag' is non-nil, then the old source file is
patched instead (some commands, such as `diff-goto-source' can change
the value of this variable when given an appropriate prefix argument).

1081
With a prefix argument, REVERSE the hunk."
1082
  (interactive "P")
1083
  (destructuring-bind (buf line-offset pos old new &optional switched)
1084 1085
      (diff-find-source-location nil reverse)
    (cond
1086 1087
     ((null line-offset)
      (error "Can't find the text to patch"))
1088 1089 1090 1091 1092 1093 1094 1095 1096
     ((and switched
	   ;; A reversed patch was detected, perhaps apply it in reverse
	   (not (save-window-excursion
		  (pop-to-buffer buf)
		  (goto-char (+ pos (cdr old)))
		  (y-or-n-p
		   (if reverse
		       "Hunk hasn't been applied yet; apply it now? "
		     "Hunk has already been applied; undo it? ")))))
1097
      (message "(Nothing done)"))
1098
     (t
1099 1100 1101 1102 1103 1104 1105 1106 1107 1108
      ;; Apply the hunk
      (with-current-buffer buf
	(goto-char pos)
	(delete-char (length (car old)))
	(insert (car new)))
      ;; Display BUF in a window
      (set-window-point (display-buffer buf) (+ pos (cdr new)))
      (diff-hunk-status-msg line-offset (diff-xor switched reverse) nil)
      (when diff-advance-after-apply-hunk
	(diff-hunk-next))))))
1109

1110 1111 1112

(defun diff-test-hunk (&optional reverse)
  "See whether it's possible to apply the current hunk.
1113
With a prefix argument, try to REVERSE the hunk."
1114
  (interactive "P")
1115 1116
  (destructuring-bind (buf line-offset pos src dst &optional switched)
      (diff-find-source-location nil reverse)
1117
    (set-window-point (display-buffer buf) (+ pos (cdr src)))
1118
    (diff-hunk-status-msg line-offset (diff-xor reverse switched) t)))
1119

1120 1121 1122 1123

(defun diff-goto-source (&optional other-file)
  "Jump to the corresponding source line.
`diff-jump-to-old-file-flag' (or its opposite if the OTHER-FILE prefix arg
1124
is given) determines whether to jump to the old or the new file.
1125 1126 1127
If the prefix arg is bigger than 8 (for example with \\[universal-argument] \\[universal-argument])
  then `diff-jump-to-old-file-flag' is also set, for the next invocations."
  (interactive "P")
1128 1129 1130 1131 1132 1133 1134 1135
  ;; When pointing at a removal line, we probably want to jump to
  ;; the old location, and else to the new (i.e. as if reverting).
  ;; This is a convenient detail when using smerge-diff.
  (let ((rev (not (save-excursion (beginning-of-line) (looking-at "[-<]")))))
    (destructuring-bind (buf line-offset pos src dst &optional switched)
	(diff-find-source-location other-file rev)
      (pop-to-buffer buf)
      (goto-char (+ pos (cdr src)))
Miles Bader's avatar
Miles Bader committed
1136
      (diff-hunk-status-msg line-offset (diff-xor rev switched) t))))
1137

1138

1139
(defun diff-current-defun ()
1140 1141
  "Find the name of function at point.
For use in `add-log-current-defun-function'."