(eudc-external-viewers): Do not use xv, it is not free.
[bpt/emacs.git] / lisp / diff-mode.el
CommitLineData
b532d575 1;;; diff-mode.el --- a mode for viewing/editing context diffs
610a6418 2
2b960ac0 3;; Copyright (C) 1998, 1999, 2000, 2001 Free Software Foundation, Inc.
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4
5;; Author: Stefan Monnier <monnier@cs.yale.edu>
b532d575 6;; Keywords: convenience patch diff
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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., 59 Temple Place - Suite 330,
23;; Boston, MA 02111-1307, USA.
24
25;;; Commentary:
26
cdbb79c1 27;; Provides support for font-lock, outline, navigation
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28;; commands, editing and various conversions as well as jumping
29;; to the corresponding source file.
30
b532d575
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31;; Inspired by Pavel Machek's patch-mode.el (<pavel@atrey.karlin.mff.cuni.cz>)
32;; Some efforts were spent to have it somewhat compatible with XEmacs'
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33;; diff-mode as well as with compilation-minor-mode
34
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35;; Bugs:
36
027ac3f8 37;; - Reverse doesn't work with normal diffs.
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38
39;; Todo:
40
027ac3f8 41;; - Improve narrowed-view support.
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42;; - re-enable (conditionally) the `compile' support after improving it to use
43;; the same code as diff-goto-source.
027ac3f8 44;; - Support for # comments in context->unified.
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45;; - Allow diff.el to use diff-mode.
46;; This mostly means ability to jump from half-hunk to half-hunk
47;; in context (and normal) diffs and to jump to the corresponding
48;; (i.e. new or old) file.
027ac3f8 49;; - Handle `diff -b' output in context->unified.
610a6418 50
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51;; Low priority:
52;; - Spice up the minor-mode with font-lock support.
53;; - Recognize pcl-cvs' special string for `cvs-execute-single'.
54
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55;;; Code:
56
57(eval-when-compile (require 'cl))
58
59
60(defgroup diff-mode ()
3cec9c57 61 "Major mode for viewing/editing diffs"
ccce6558 62 :version "21.1"
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63 :group 'tools
64 :group 'diff)
65
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66(defcustom diff-default-read-only t
67 "If non-nil, `diff-mode' buffers default to being read-only."
68 :type 'boolean
69 :group 'diff-mode)
70
e8a1ed31 71(defcustom diff-jump-to-old-file nil
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72 "*Non-nil means `diff-goto-source' jumps to the old file.
73Else, it jumps to the new file."
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74 :type '(boolean))
75
e8a1ed31 76(defcustom diff-update-on-the-fly t
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77 "*Non-nil means hunk headers are kept up-to-date on-the-fly.
78When editing a diff file, the line numbers in the hunk headers
79need to be kept consistent with the actual diff. This can
80either be done on the fly (but this sometimes interacts poorly with the
81undo mechanism) or whenever the file is written (can be slow
82when editing big diffs)."
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83 :type '(boolean))
84
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85(defcustom diff-advance-after-apply-hunk t
86 "*Non-nil means `diff-apply-hunk' will move to the next hunk after applying."
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87 :type 'boolean)
88
89
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90(defvar diff-mode-hook nil
91 "Run after setting up the `diff-mode' major mode.")
92
93(defvar diff-outline-regexp
94 "\\([*+][*+][*+] [^0-9]\\|@@ ...\\|\\*\\*\\* [0-9].\\|--- [0-9]..\\)")
95
cd632e57 96;;;;
610a6418 97;;;; keymap, menu, ...
cd632e57 98;;;;
610a6418 99
d87e5627 100(easy-mmode-defmap diff-mode-shared-map
027ac3f8 101 '(;; From Pavel Machek's patch-mode.
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102 ("n" . diff-hunk-next)
103 ("N" . diff-file-next)
104 ("p" . diff-hunk-prev)
105 ("P" . diff-file-prev)
106 ("k" . diff-hunk-kill)
107 ("K" . diff-file-kill)
027ac3f8 108 ;; From compilation-minor-mode.
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109 ("}" . diff-file-next)
110 ("{" . diff-file-prev)
610a6418 111 ("\C-m" . diff-goto-source)
ccce6558 112 ([mouse-2] . diff-mouse-goto-source)
027ac3f8 113 ;; From XEmacs' diff-mode.
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114 ("W" . widen)
115 ;;("." . diff-goto-source) ;display-buffer
116 ;;("f" . diff-goto-source) ;find-file
117 ("o" . diff-goto-source) ;other-window
118 ;;("w" . diff-goto-source) ;other-frame
119 ;;("N" . diff-narrow)
120 ;;("h" . diff-show-header)
121 ;;("j" . diff-show-difference) ;jump to Nth diff
122 ;;("q" . diff-quit)
123 (" " . scroll-up)
124 ("\177" . scroll-down)
027ac3f8 125 ;; Our very own bindings.
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126 ("A" . diff-ediff-patch)
127 ("r" . diff-restrict-view)
128 ("R" . diff-reverse-direction)
129 ("U" . diff-context->unified)
130 ("C" . diff-unified->context))
0b82e382 131 "Basic keymap for `diff-mode', bound to various prefix keys.")
610a6418 132
d87e5627 133(easy-mmode-defmap diff-mode-map
610a6418 134 `(("\e" . ,diff-mode-shared-map)
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135 ;; From compilation-minor-mode.
136 ("\C-c\C-c" . diff-goto-source)
137 ;; Misc operations.
cd632e57 138 ("\C-c\C-s" . diff-split-hunk)
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139 ("\C-c\C-a" . diff-apply-hunk)
140 ("\C-c\C-t" . diff-test-hunk))
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141 "Keymap for `diff-mode'. See also `diff-mode-shared-map'.")
142
143(easy-menu-define diff-mode-menu diff-mode-map
144 "Menu for `diff-mode'."
145 '("Diff"
146 ["Jump to Source" diff-goto-source t]
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147 ["Apply hunk" diff-apply-hunk t]
148 ["Apply diff with Ediff" diff-ediff-patch t]
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149 ["-----" nil nil]
150 ["Reverse direction" diff-reverse-direction t]
151 ["Context -> Unified" diff-context->unified t]
152 ["Unified -> Context" diff-unified->context t]
153 ;;["Fixup Headers" diff-fixup-modifs (not buffer-read-only)]
154 ))
155
3cec9c57 156(defcustom diff-minor-mode-prefix "\C-c="
0b82e382 157 "Prefix key for `diff-minor-mode' commands."
3cec9c57 158 :type '(choice (string "\e") (string "C-c=") string))
0b82e382 159
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160(easy-mmode-defmap diff-minor-mode-map
161 `((,diff-minor-mode-prefix . ,diff-mode-shared-map))
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162 "Keymap for `diff-minor-mode'. See also `diff-mode-shared-map'.")
163
610a6418 164
cd632e57 165;;;;
610a6418 166;;;; font-lock support
cd632e57 167;;;;
610a6418 168
c0aa75f7 169(defface diff-header-face
86a27a3a 170 '((((type tty pc) (class color) (background light))
58b64ac7 171 (:foreground "blue1" :weight bold))
86a27a3a 172 (((type tty pc) (class color) (background dark))
58b64ac7 173 (:foreground "green" :weight bold))
86a27a3a 174 (((class color) (background light))
3cec9c57 175 (:background "grey85"))
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176 (((class color) (background dark))
177 (:background "grey45"))
58b64ac7 178 (t (:weight bold)))
1eabc5e6 179 "`diff-mode' face inherited by hunk and index header faces.")
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180(defvar diff-header-face 'diff-header-face)
181
610a6418 182(defface diff-file-header-face
86a27a3a 183 '((((type tty pc) (class color) (background light))
58b64ac7 184 (:foreground "yellow" :weight bold))
86a27a3a 185 (((type tty pc) (class color) (background dark))
58b64ac7 186 (:foreground "cyan" :weight bold))
86a27a3a 187 (((class color) (background light))
58b64ac7 188 (:background "grey70" :weight bold))
9244f2c7 189 (((class color) (background dark))
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190 (:background "grey60" :weight bold))
191 (t (:weight bold))) ; :height 1.3
1eabc5e6 192 "`diff-mode' face used to highlight file header lines.")
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193(defvar diff-file-header-face 'diff-file-header-face)
194
195(defface diff-index-face
c0aa75f7 196 '((t (:inherit diff-file-header-face)))
1eabc5e6 197 "`diff-mode' face used to highlight index header lines.")
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198(defvar diff-index-face 'diff-index-face)
199
200(defface diff-hunk-header-face
c0aa75f7 201 '((t (:inherit diff-header-face)))
1eabc5e6 202 "`diff-mode' face used to highlight hunk header lines.")
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203(defvar diff-hunk-header-face 'diff-hunk-header-face)
204
205(defface diff-removed-face
c0aa75f7 206 '((t (:inherit diff-changed-face)))
1eabc5e6 207 "`diff-mode' face used to highlight removed lines.")
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208(defvar diff-removed-face 'diff-removed-face)
209
210(defface diff-added-face
c0aa75f7 211 '((t (:inherit diff-changed-face)))
1eabc5e6 212 "`diff-mode' face used to highlight added lines.")
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213(defvar diff-added-face 'diff-added-face)
214
215(defface diff-changed-face
86a27a3a 216 '((((type tty pc) (class color) (background light))
58b64ac7 217 (:foreground "magenta" :weight bold :slant italic))
86a27a3a 218 (((type tty pc) (class color) (background dark))
58b64ac7 219 (:foreground "yellow" :weight bold :slant italic))
86a27a3a 220 (t ()))
1eabc5e6 221 "`diff-mode' face used to highlight changed lines.")
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222(defvar diff-changed-face 'diff-changed-face)
223
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224(defface diff-function-face
225 '((t (:inherit diff-context-face)))
1eabc5e6 226 "`diff-mode' face used to highlight function names produced by \"diff -p\".")
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227(defvar diff-function-face 'diff-function-face)
228
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229(defface diff-context-face
230 '((((class color) (background light))
231 (:foreground "grey50"))
232 (((class color) (background dark))
233 (:foreground "grey70"))
234 (t ))
1eabc5e6 235 "`diff-mode' face used to highlight context and other side-information.")
9244f2c7 236(defvar diff-context-face 'diff-context-face)
c0aa75f7 237
7dfb000f 238(defface diff-nonexistent-face
469fc0a2 239 '((t (:inherit diff-file-header-face)))
1eabc5e6 240 "`diff-mode' face used to highlight nonexistent files in recursive diffs.")
7dfb000f 241(defvar diff-nonexistent-face 'diff-nonexistent-face)
469fc0a2 242
610a6418 243(defvar diff-font-lock-keywords
c0aa75f7 244 '(("^\\(@@ -[0-9,]+ \\+[0-9,]+ @@\\)\\(.*\\)$" ;unified
19e713d8 245 (1 diff-hunk-header-face)
34460354 246 (2 diff-function-face))
469fc0a2 247 ("^--- .+ ----$" . diff-hunk-header-face) ;context
a62d56ab 248 ("^\\(\\*\\{15\\}\\)\\(.*\\)$" ;context
19e713d8 249 (1 diff-hunk-header-face)
34460354 250 (2 diff-function-face))
370d860c 251 ("^\\*\\*\\* .+ \\*\\*\\*\\*". diff-hunk-header-face) ;context
a6373340 252 ("^\\(---\\|\\+\\+\\+\\|\\*\\*\\*\\) \\(\\S-+\\)\\(.*[^*-]\\)?\n"
c0aa75f7 253 (0 diff-header-face) (2 diff-file-header-face prepend))
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254 ("^[0-9,]+[acd][0-9,]+$" . diff-hunk-header-face)
255 ("^!.*\n" . diff-changed-face) ;context
256 ("^[+>].*\n" . diff-added-face)
257 ("^[-<].*\n" . diff-removed-face)
c0aa75f7 258 ("^Index: \\(.+\\).*\n" (0 diff-header-face) (1 diff-index-face prepend))
7dfb000f 259 ("^Only in .*\n" . diff-nonexistent-face)
0e104800 260 ("^#.*" . font-lock-string-face)
9244f2c7 261 ("^[^-=+*!<>].*\n" . diff-context-face)))
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262
263(defconst diff-font-lock-defaults
0e104800 264 '(diff-font-lock-keywords t nil nil nil (font-lock-multiline . nil)))
610a6418 265
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266(defvar diff-imenu-generic-expression
267 ;; Prefer second name as first is most likely to be a backup or
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268 ;; version-control name. The [\t\n] at the end of the unidiff pattern
269 ;; catches Debian source diff files (which lack the trailing date).
270 '((nil "\\+\\+\\+\\ \\([^\t\n]+\\)[\t\n]" 1) ; unidiffs
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271 (nil "^--- \\([^\t\n]+\\)\t.*\n\\*" 1))) ; context diffs
272
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273;;;;
274;;;; Compile support
275;;;;
276
277(defvar diff-file-regexp-alist
278 '(("Index: \\(.+\\)" 1)))
279
280(defvar diff-error-regexp-alist
281 '(("@@ -\\([0-9]+\\),[0-9]+ \\+\\([0-9]+\\),[0-9]+ @@" nil 2)
282 ("--- \\([0-9]+\\),[0-9]+ ----" nil 1)
283 ("\\([0-9]+\\)\\(,[0-9]+\\)?[adc]\\([0-9]+\\)" nil 3)))
284
cd632e57 285;;;;
610a6418 286;;;; Movement
cd632e57 287;;;;
610a6418 288
c0078a04 289(defconst diff-hunk-header-re "^\\(@@ -[0-9,]+ \\+[0-9,]+ @@.*\\|\\*\\{15\\}.*\n\\*\\*\\* .+ \\*\\*\\*\\*\\|[0-9]+\\(,[0-9]+\\)?[acd][0-9]+\\(,[0-9]+\\)?\\)$")
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290(defconst diff-file-header-re (concat "^\\(--- .+\n\\+\\+\\+\\|\\*\\*\\* .+\n---\\|[^-+!<>0-9@* ]\\).+\n" (substring diff-hunk-header-re 1)))
291(defvar diff-narrowed-to nil)
292
293(defun diff-end-of-hunk (&optional style)
294 (if (looking-at diff-hunk-header-re) (goto-char (match-end 0)))
0e104800 295 (let ((end (and (re-search-forward (case style
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296 ;; A `unified' header is ambiguous.
297 (unified (concat "^[^-+# \\]\\|"
298 diff-file-header-re))
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299 (context "^[^-+#! \\]")
300 (normal "^[^<>#\\]")
301 (t "^[^-+#!<> \\]"))
302 nil t)
303 (match-beginning 0))))
304 ;; The return value is used by easy-mmode-define-navigation.
305 (goto-char (or end (point-max)))))
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306
307(defun diff-beginning-of-hunk ()
308 (beginning-of-line)
309 (unless (looking-at diff-hunk-header-re)
310 (forward-line 1)
311 (condition-case ()
312 (re-search-backward diff-hunk-header-re)
313 (error (error "Can't find the beginning of the hunk")))))
314
315(defun diff-beginning-of-file ()
316 (beginning-of-line)
317 (unless (looking-at diff-file-header-re)
318 (forward-line 2)
319 (condition-case ()
320 (re-search-backward diff-file-header-re)
321 (error (error "Can't find the beginning of the file")))))
322
323(defun diff-end-of-file ()
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324 (re-search-forward "^[-+#!<>0-9@* \\]" nil t)
325 (re-search-forward "^[^-+#!<>0-9@* \\]" nil 'move)
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326 (beginning-of-line))
327
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328;; Define diff-{hunk,file}-{prev,next}
329(easy-mmode-define-navigation
330 diff-hunk diff-hunk-header-re "hunk" diff-end-of-hunk)
331(easy-mmode-define-navigation
332 diff-file diff-file-header-re "file" diff-end-of-hunk)
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333
334(defun diff-restrict-view (&optional arg)
335 "Restrict the view to the current hunk.
336If the prefix ARG is given, restrict the view to the current file instead."
337 (interactive "P")
338 (save-excursion
339 (if arg (diff-beginning-of-file) (diff-beginning-of-hunk))
340 (narrow-to-region (point)
341 (progn (if arg (diff-end-of-file) (diff-end-of-hunk))
342 (point)))
343 (set (make-local-variable 'diff-narrowed-to) (if arg 'file 'hunk))))
344
345
d87e5627 346(defun diff-hunk-kill ()
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347 "Kill current hunk."
348 (interactive)
349 (diff-beginning-of-hunk)
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350 (let* ((start (point))
351 (nexthunk (ignore-errors (diff-hunk-next) (point)))
352 (firsthunk (ignore-errors
353 (goto-char start)
354 (diff-beginning-of-file) (diff-hunk-next) (point)))
355 (nextfile (ignore-errors (diff-file-next) (point))))
356 (goto-char start)
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357 (if (and firsthunk (= firsthunk start)
358 (or (null nexthunk)
359 (and nextfile (> nexthunk nextfile))))
1eabc5e6 360 ;; It's the only hunk for this file, so kill the file.
d87e5627 361 (diff-file-kill)
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362 (diff-end-of-hunk)
363 (kill-region start (point)))))
364
d87e5627 365(defun diff-file-kill ()
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366 "Kill current file's hunks."
367 (interactive)
368 (diff-beginning-of-file)
369 (let* ((start (point))
370 (prevhunk (save-excursion
371 (ignore-errors
d87e5627 372 (diff-hunk-prev) (point))))
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373 (index (save-excursion
374 (re-search-backward "^Index: " prevhunk t))))
375 (when index (setq start index))
376 (diff-end-of-file)
377 (kill-region start (point))))
378
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379(defun diff-kill-junk ()
380 "Kill spurious empty diffs."
381 (interactive)
382 (save-excursion
383 (let ((inhibit-read-only t))
384 (goto-char (point-min))
385 (while (re-search-forward (concat "^\\(Index: .*\n\\)"
386 "\\([^-+!* <>].*\n\\)*?"
387 "\\(\\(Index:\\) \\|"
388 diff-file-header-re "\\)")
389 nil t)
390 (delete-region (if (match-end 4) (match-beginning 0) (match-end 1))
391 (match-beginning 3))
392 (beginning-of-line)))))
393
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394(defun diff-count-matches (re start end)
395 (save-excursion
396 (let ((n 0))
397 (goto-char start)
398 (while (re-search-forward re end t) (incf n))
399 n)))
400
401(defun diff-split-hunk ()
402 "Split the current (unified diff) hunk at point into two hunks."
403 (interactive)
404 (beginning-of-line)
405 (let ((pos (point))
406 (start (progn (diff-beginning-of-hunk) (point))))
407 (unless (looking-at "@@ -\\([0-9]+\\),[0-9]+ \\+\\([0-9]+\\),[0-9]+ @@")
408 (error "diff-split-hunk only works on unified context diffs"))
409 (forward-line 1)
410 (let* ((start1 (string-to-number (match-string 1)))
411 (start2 (string-to-number (match-string 2)))
412 (newstart1 (+ start1 (diff-count-matches "^[- \t]" (point) pos)))
413 (newstart2 (+ start2 (diff-count-matches "^[+ \t]" (point) pos))))
414 (goto-char pos)
415 ;; Hopefully the after-change-function will not screw us over.
416 (insert "@@ -" (number-to-string newstart1) ",1 +"
417 (number-to-string newstart2) ",1 @@\n")
418 ;; Fix the original hunk-header.
419 (diff-fixup-modifs start pos))))
420
421
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422;;;;
423;;;; jump to other buffers
424;;;;
425
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426(defvar diff-remembered-files-alist nil)
427
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428(defun diff-filename-drop-dir (file)
429 (when (string-match "/" file) (substring file (match-end 0))))
430
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431(defun diff-merge-strings (ancestor from to)
432 "Merge the diff between ANCESTOR and FROM into TO.
433Returns the merged string if successful or nil otherwise.
d87e5627 434The strings are assumed not to contain any \"\\n\" (i.e. end of line).
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435If ANCESTOR = FROM, returns TO.
436If ANCESTOR = TO, returns FROM.
437The heuristic is simplistic and only really works for cases
438like \(diff-merge-strings \"b/foo\" \"b/bar\" \"/a/c/foo\")."
439 ;; Ideally, we want:
440 ;; AMB ANB CMD -> CND
441 ;; but that's ambiguous if `foo' or `bar' is empty:
442 ;; a/foo a/foo1 b/foo.c -> b/foo1.c but not 1b/foo.c or b/foo.c1
d87e5627 443 (let ((str (concat ancestor "\n" from "\n" to)))
0b82e382 444 (when (and (string-match (concat
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445 "\\`\\(.*?\\)\\(.*\\)\\(.*\\)\n"
446 "\\1\\(.*\\)\\3\n"
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447 "\\(.*\\(\\2\\).*\\)\\'") str)
448 (equal to (match-string 5 str)))
449 (concat (substring str (match-beginning 5) (match-beginning 6))
450 (match-string 4 str)
451 (substring str (match-end 6) (match-end 5))))))
452
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453(defun diff-find-file-name (&optional old)
454 "Return the file corresponding to the current patch.
455Non-nil OLD means that we want the old file."
456 (save-excursion
457 (unless (looking-at diff-file-header-re)
458 (or (ignore-errors (diff-beginning-of-file))
459 (re-search-forward diff-file-header-re nil t)))
460 (let* ((limit (save-excursion
461 (condition-case ()
d87e5627 462 (progn (diff-hunk-prev) (point))
610a6418 463 (error (point-min)))))
83b7b03b 464 (header-files
30cdf899 465 (if (looking-at "[-*][-*][-*] \\(\\S-+\\)\\(\\s-.*\\)?\n[-+][-+][-+] \\(\\S-+\\)")
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466 (list (if old (match-string 1) (match-string 3))
467 (if old (match-string 3) (match-string 1)))
83b7b03b 468 (forward-line 1) nil))
610a6418 469 (fs (append
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470 (when (save-excursion
471 (re-search-backward "^Index: \\(.+\\)" limit t))
472 (list (match-string 1)))
83b7b03b 473 header-files
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474 (when (re-search-backward "^diff \\(-\\S-+ +\\)*\\(\\S-+\\)\\( +\\(\\S-+\\)\\)?" nil t)
475 (list (if old (match-string 2) (match-string 4))
476 (if old (match-string 4) (match-string 2))))))
0b82e382 477 (fs (delq nil fs)))
610a6418 478 (or
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479 ;; use any previously used preference
480 (cdr (assoc fs diff-remembered-files-alist))
481 ;; try to be clever and use previous choices as an inspiration
482 (dolist (rf diff-remembered-files-alist)
483 (let ((newfile (diff-merge-strings (caar rf) (car fs) (cdr rf))))
484 (if (and newfile (file-exists-p newfile)) (return newfile))))
485 ;; look for each file in turn. If none found, try again but
486 ;; ignoring the first level of directory, ...
487 (do* ((files fs (delq nil (mapcar 'diff-filename-drop-dir files)))
488 (file nil nil))
489 ((or (null files)
490 (setq file (do* ((files files (cdr files))
491 (file (car files) (car files)))
492 ((or (null file) (file-exists-p file))
493 file))))
494 file))
495 ;; <foo>.rej patches implicitly apply to <foo>
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496 (and (string-match "\\.rej\\'" (or buffer-file-name ""))
497 (let ((file (substring buffer-file-name 0 (match-beginning 0))))
498 (when (file-exists-p file) file)))
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499 ;; if all else fails, ask the user
500 (let ((file (read-file-name (format "Use file %s: " (or (first fs) ""))
501 nil (first fs) t (first fs))))
502 (set (make-local-variable 'diff-remembered-files-alist)
503 (cons (cons fs file) diff-remembered-files-alist))
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504 file)))))
505
1b1b5dae 506
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507(defun diff-mouse-goto-source (event)
508 "Run `diff-goto-source' for the diff at a mouse click."
509 (interactive "e")
510 (save-excursion
511 (mouse-set-point event)
512 (diff-goto-source)))
610a6418 513
281096ed 514
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515(defun diff-ediff-patch ()
516 "Call `ediff-patch-file' on the current buffer."
517 (interactive)
518 (condition-case err
0e104800 519 (ediff-patch-file nil (current-buffer))
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520 (wrong-number-of-arguments (ediff-patch-file))))
521
522;;;;
523;;;; Conversion functions
524;;;;
525
526;;(defvar diff-inhibit-after-change nil
527;; "Non-nil means inhibit `diff-mode's after-change functions.")
528
529(defun diff-unified->context (start end)
530 "Convert unified diffs to context diffs.
531START and END are either taken from the region (if a prefix arg is given) or
532else cover the whole bufer."
533 (interactive (if current-prefix-arg
534 (list (mark) (point))
535 (list (point-min) (point-max))))
536 (unless (markerp end) (setq end (copy-marker end)))
537 (let (;;(diff-inhibit-after-change t)
538 (inhibit-read-only t))
539 (save-excursion
540 (goto-char start)
c0078a04 541 (while (and (re-search-forward "^\\(\\(---\\) .+\n\\(\\+\\+\\+\\) .+\\|@@ -\\([0-9]+\\),\\([0-9]+\\) \\+\\([0-9]+\\),\\([0-9]+\\) @@.*\\)$" nil t)
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542 (< (point) end))
543 (combine-after-change-calls
544 (if (match-beginning 2)
0e104800 545 ;; we matched a file header
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546 (progn
547 ;; use reverse order to make sure the indices are kept valid
548 (replace-match "---" t t nil 3)
549 (replace-match "***" t t nil 2))
550 ;; we matched a hunk header
551 (let ((line1 (match-string 4))
552 (lines1 (match-string 5))
553 (line2 (match-string 6))
554 (lines2 (match-string 7)))
555 (replace-match
556 (concat "***************\n*** " line1 ","
557 (number-to-string (+ (string-to-number line1)
558 (string-to-number lines1)
559 -1)) " ****"))
560 (forward-line 1)
561 (save-restriction
562 (narrow-to-region (point)
563 (progn (diff-end-of-hunk 'unified) (point)))
564 (let ((hunk (buffer-string)))
565 (goto-char (point-min))
566 (if (not (save-excursion (re-search-forward "^-" nil t)))
567 (delete-region (point) (point-max))
568 (goto-char (point-max))
569 (let ((modif nil) last-pt)
570 (while (progn (setq last-pt (point))
571 (= (forward-line -1) 0))
572 (case (char-after)
573 (? (insert " ") (setq modif nil) (backward-char 1))
574 (?+ (delete-region (point) last-pt) (setq modif t))
575 (?- (if (not modif)
576 (progn (forward-char 1)
577 (insert " "))
578 (delete-char 1)
579 (insert "! "))
580 (backward-char 2))
581 (?\\ (when (save-excursion (forward-line -1)
582 (= (char-after) ?+))
583 (delete-region (point) last-pt) (setq modif t)))
584 (t (setq modif nil))))))
585 (goto-char (point-max))
586 (save-excursion
587 (insert "--- " line2 ","
588 (number-to-string (+ (string-to-number line2)
589 (string-to-number lines2)
590 -1)) " ----\n" hunk))
591 ;;(goto-char (point-min))
592 (forward-line 1)
593 (if (not (save-excursion (re-search-forward "^+" nil t)))
594 (delete-region (point) (point-max))
595 (let ((modif nil) (delete nil))
596 (while (not (eobp))
597 (case (char-after)
598 (? (insert " ") (setq modif nil) (backward-char 1))
599 (?- (setq delete t) (setq modif t))
600 (?+ (if (not modif)
601 (progn (forward-char 1)
602 (insert " "))
603 (delete-char 1)
604 (insert "! "))
605 (backward-char 2))
606 (?\\ (when (save-excursion (forward-line 1)
607 (not (eobp)))
608 (setq delete t) (setq modif t)))
609 (t (setq modif nil)))
610 (let ((last-pt (point)))
611 (forward-line 1)
612 (when delete
613 (delete-region last-pt (point))
614 (setq delete nil)))))))))))))))
615
616(defun diff-context->unified (start end)
617 "Convert context diffs to unified diffs.
618START and END are either taken from the region (if a prefix arg is given) or
619else cover the whole bufer."
620 (interactive (if current-prefix-arg
621 (list (mark) (point))
622 (list (point-min) (point-max))))
623 (unless (markerp end) (setq end (copy-marker end)))
624 (let (;;(diff-inhibit-after-change t)
625 (inhibit-read-only t))
626 (save-excursion
627 (goto-char start)
c0078a04 628 (while (and (re-search-forward "^\\(\\(\\*\\*\\*\\) .+\n\\(---\\) .+\\|\\*\\{15\\}.*\n\\*\\*\\* \\([0-9]+\\),\\(-?[0-9]+\\) \\*\\*\\*\\*\\)$" nil t)
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629 (< (point) end))
630 (combine-after-change-calls
631 (if (match-beginning 2)
632 ;; we matched a file header
633 (progn
634 ;; use reverse order to make sure the indices are kept valid
635 (replace-match "+++" t t nil 3)
636 (replace-match "---" t t nil 2))
637 ;; we matched a hunk header
638 (let ((line1s (match-string 4))
639 (line1e (match-string 5))
640 (pt1 (match-beginning 0)))
641 (replace-match "")
642 (unless (re-search-forward
643 "^--- \\([0-9]+\\),\\(-?[0-9]+\\) ----$" nil t)
644 (error "Can't find matching `--- n1,n2 ----' line"))
645 (let ((line2s (match-string 1))
646 (line2e (match-string 2))
647 (pt2 (progn
648 (delete-region (progn (beginning-of-line) (point))
649 (progn (forward-line 1) (point)))
650 (point-marker))))
651 (goto-char pt1)
652 (forward-line 1)
653 (while (< (point) pt2)
654 (case (char-after)
655 ((?! ?-) (delete-char 2) (insert "-") (forward-line 1))
656 (?\ ;merge with the other half of the chunk
657 (let* ((endline2
658 (save-excursion
659 (goto-char pt2) (forward-line 1) (point)))
660 (c (char-after pt2)))
661 (case c
662 ((?! ?+)
663 (insert "+"
664 (prog1 (buffer-substring (+ pt2 2) endline2)
665 (delete-region pt2 endline2))))
666 (?\ ;FIXME: check consistency
667 (delete-region pt2 endline2)
668 (delete-char 1)
669 (forward-line 1))
670 (?\\ (forward-line 1))
671 (t (delete-char 1) (forward-line 1)))))
672 (t (forward-line 1))))
673 (while (looking-at "[+! ] ")
674 (if (/= (char-after) ?!) (forward-char 1)
675 (delete-char 1) (insert "+"))
676 (delete-char 1) (forward-line 1))
677 (save-excursion
678 (goto-char pt1)
679 (insert "@@ -" line1s ","
680 (number-to-string (- (string-to-number line1e)
681 (string-to-number line1s)
682 -1))
683 " +" line2s ","
684 (number-to-string (- (string-to-number line2e)
685 (string-to-number line2s)
686 -1)) " @@"))))))))))
687
688(defun diff-reverse-direction (start end)
689 "Reverse the direction of the diffs.
690START and END are either taken from the region (if a prefix arg is given) or
691else cover the whole bufer."
692 (interactive (if current-prefix-arg
693 (list (mark) (point))
694 (list (point-min) (point-max))))
695 (unless (markerp end) (setq end (copy-marker end)))
696 (let (;;(diff-inhibit-after-change t)
697 (inhibit-read-only t))
698 (save-excursion
699 (goto-char start)
c0078a04 700 (while (and (re-search-forward "^\\(\\([-*][-*][-*] \\)\\(.+\\)\n\\([-+][-+][-+] \\)\\(.+\\)\\|\\*\\{15\\}.*\n\\*\\*\\* \\(.+\\) \\*\\*\\*\\*\\|@@ -\\([0-9,]+\\) \\+\\([0-9,]+\\) @@.*\\)$" nil t)
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701 (< (point) end))
702 (combine-after-change-calls
703 (cond
704 ;; a file header
705 ((match-beginning 2) (replace-match "\\2\\5\n\\4\\3" nil))
706 ;; a context-diff hunk header
707 ((match-beginning 6)
708 (let ((pt-lines1 (match-beginning 6))
709 (lines1 (match-string 6)))
710 (replace-match "" nil nil nil 6)
711 (forward-line 1)
712 (let ((half1s (point)))
0e104800 713 (while (looking-at "[-! \\][ \t]\\|#")
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714 (when (= (char-after) ?-) (delete-char 1) (insert "+"))
715 (forward-line 1))
fef8c55b 716 (let ((half1 (delete-and-extract-region half1s (point))))
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717 (unless (looking-at "^--- \\([0-9]+,-?[0-9]+\\) ----$")
718 (insert half1)
719 (error "Can't find matching `--- n1,n2 ----' line"))
720 (let ((str1 (match-string 1)))
721 (replace-match lines1 nil nil nil 1)
722 (forward-line 1)
723 (let ((half2s (point)))
0e104800 724 (while (looking-at "[!+ \\][ \t]\\|#")
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725 (when (= (char-after) ?+) (delete-char 1) (insert "-"))
726 (forward-line 1))
fef8c55b 727 (let ((half2 (delete-and-extract-region half2s (point))))
0e104800 728 (insert (or half1 ""))
610a6418 729 (goto-char half1s)
0e104800 730 (insert (or half2 ""))))
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731 (goto-char pt-lines1)
732 (insert str1))))))
733 ;; a unified-diff hunk header
734 ((match-beginning 7)
735 (replace-match "@@ -\\8 +\\7 @@" nil)
736 (forward-line 1)
737 (let ((c (char-after)) first last)
738 (while (case (setq c (char-after))
739 (?- (setq first (or first (point)))
740 (delete-char 1) (insert "+") t)
741 (?+ (setq last (or last (point)))
742 (delete-char 1) (insert "-") t)
0e104800 743 ((?\\ ?#) t)
610a6418 744 (t (when (and first last (< first last))
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745 (let ((str
746 (save-excursion
747 (delete-and-extract-region first last))))
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748 (insert str)))
749 (setq first nil last nil)
750 (equal ?\ c)))
751 (forward-line 1))))))))))
752
753(defun diff-fixup-modifs (start end)
754 "Fixup the hunk headers (in case the buffer was modified).
755START and END are either taken from the region (if a prefix arg is given) or
756else cover the whole bufer."
757 (interactive (if current-prefix-arg
758 (list (mark) (point))
759 (list (point-min) (point-max))))
760 (let ((inhibit-read-only t))
761 (save-excursion
762 (goto-char end) (diff-end-of-hunk)
763 (let ((plus 0) (minus 0) (space 0) (bang 0))
764 (while (and (= (forward-line -1) 0) (<= start (point)))
c0078a04 765 (if (not (looking-at "\\(@@ -[0-9,]+ \\+[0-9,]+ @@.*\\|[-*][-*][-*] .+ [-*][-*][-*][-*]\\)$"))
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766 (case (char-after)
767 (?\ (incf space))
768 (?+ (incf plus))
769 (?- (incf minus))
770 (?! (incf bang))
0e104800 771 ((?\\ ?#) nil)
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772 (t (setq space 0 plus 0 minus 0 bang 0)))
773 (cond
c0078a04 774 ((looking-at "@@ -[0-9]+,\\([0-9]*\\) \\+[0-9]+,\\([0-9]*\\) @@.*$")
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775 (let* ((old1 (match-string 1))
776 (old2 (match-string 2))
777 (new1 (number-to-string (+ space minus)))
778 (new2 (number-to-string (+ space plus))))
779 (unless (string= new2 old2) (replace-match new2 t t nil 2))
780 (unless (string= new1 old1) (replace-match new1 t t nil 1))))
781 ((looking-at "--- \\([0-9]+\\),\\([0-9]*\\) ----$")
782 (when (> (+ space bang plus) 0)
783 (let* ((old1 (match-string 1))
784 (old2 (match-string 2))
785 (new (number-to-string
786 (+ space bang plus -1 (string-to-number old1)))))
787 (unless (string= new old2) (replace-match new t t nil 2)))))
788 ((looking-at "\\*\\*\\* \\([0-9]+\\),\\(-?[0-9]*\\) \\*\\*\\*\\*$")
789 (when (> (+ space bang minus) 0)
790 (let* ((old (match-string 1))
791 (new (format
792 (concat "%0" (number-to-string (length old)) "d")
793 (+ space bang minus -1 (string-to-number old)))))
794 (unless (string= new old) (replace-match new t t nil 2))))))
795 (setq space 0 plus 0 minus 0 bang 0)))))))
796
797;;;;
798;;;; Hooks
799;;;;
800
801(defun diff-write-contents-hooks ()
802 "Fixup hunk headers if necessary."
803 (if (buffer-modified-p) (diff-fixup-modifs (point-min) (point-max)))
804 nil)
805
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806;; It turns out that making changes in the buffer from within an
807;; *-change-function is asking for trouble, whereas making them
808;; from a post-command-hook doesn't pose much problems
809(defvar diff-unhandled-changes nil)
810(defun diff-after-change-function (beg end len)
811 "Remember to fixup the hunk header.
812See `after-change-functions' for the meaning of BEG, END and LEN."
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813 ;; Ignoring changes when inhibit-read-only is set is strictly speaking
814 ;; incorrect, but it turns out that inhibit-read-only is normally not set
815 ;; inside editing commands, while it tends to be set when the buffer gets
816 ;; updated by an async process or by a conversion function, both of which
817 ;; would rather not be uselessly slowed down by this hook.
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818 (when (and (not undo-in-progress) (not inhibit-read-only))
819 (if diff-unhandled-changes
820 (setq diff-unhandled-changes
821 (cons (min beg (car diff-unhandled-changes))
822 (max beg (cdr diff-unhandled-changes))))
823 (setq diff-unhandled-changes (cons beg end)))))
824
825(defun diff-post-command-hook ()
826 "Fixup hunk headers if necessary."
827 (when (consp diff-unhandled-changes)
828 (ignore-errors
829 (save-excursion
fef8c55b 830 (goto-char (car diff-unhandled-changes))
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831 ;; We used to fixup modifs on all the changes, but it turns out
832 ;; that it's safer not to do it on big changes, for example
833 ;; when yanking a big diff, since we might then screw up perfectly
834 ;; correct values. -stef
835 ;; (unless (ignore-errors
836 ;; (diff-beginning-of-hunk)
837 ;; (save-excursion
838 ;; (diff-end-of-hunk)
839 ;; (> (point) (car diff-unhandled-changes))))
840 ;; (goto-char (car diff-unhandled-changes))
841 ;; (re-search-forward diff-hunk-header-re (cdr diff-unhandled-changes))
842 ;; (diff-beginning-of-hunk))
843 ;; (diff-fixup-modifs (point) (cdr diff-unhandled-changes))
844 (diff-beginning-of-hunk)
845 (when (save-excursion
846 (diff-end-of-hunk)
847 (> (point) (cdr diff-unhandled-changes)))
848 (diff-fixup-modifs (point) (cdr diff-unhandled-changes)))))
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849 (setq diff-unhandled-changes nil)))
850
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851;;;;
852;;;; The main function
853;;;;
854
610a6418 855;;;###autoload
d87e5627 856(define-derived-mode diff-mode fundamental-mode "Diff"
0b82e382 857 "Major mode for viewing/editing context diffs.
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858Supports unified and context diffs as well as (to a lesser extent)
859normal diffs.
860When the buffer is read-only, the ESC prefix is not necessary."
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861 (set (make-local-variable 'font-lock-defaults) diff-font-lock-defaults)
862 (set (make-local-variable 'outline-regexp) diff-outline-regexp)
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863 (set (make-local-variable 'imenu-generic-expression)
864 diff-imenu-generic-expression)
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865 ;; These are not perfect. They would be better done separately for
866 ;; context diffs and unidiffs.
867 ;; (set (make-local-variable 'paragraph-start)
868 ;; (concat "@@ " ; unidiff hunk
869 ;; "\\|\\*\\*\\* " ; context diff hunk or file start
870 ;; "\\|--- [^\t]+\t")) ; context or unidiff file
871 ;; ; start (first or second line)
872 ;; (set (make-local-variable 'paragraph-separate) paragraph-start)
873 ;; (set (make-local-variable 'page-delimiter) "--- [^\t]+\t")
874 ;; compile support
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875
876 ;;;; compile support is not good enough yet. Also it can be annoying
877 ;; and should thus only be enabled conditionally.
878 ;; (set (make-local-variable 'compilation-file-regexp-alist)
879 ;; diff-file-regexp-alist)
880 ;; (set (make-local-variable 'compilation-error-regexp-alist)
881 ;; diff-error-regexp-alist)
882 ;; (when (string-match "\\.rej\\'" (or buffer-file-name ""))
883 ;; (set (make-local-variable 'compilation-current-file)
884 ;; (substring buffer-file-name 0 (match-beginning 0))))
885 ;; (compilation-shell-minor-mode 1)
886
769dd0f1 887 (when (and (> (point-max) (point-min)) diff-default-read-only)
2b960ac0 888 (toggle-read-only t))
769dd0f1 889 ;; setup change hooks
e8a1ed31 890 (if (not diff-update-on-the-fly)
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891 (add-hook 'write-contents-hooks 'diff-write-contents-hooks)
892 (make-local-variable 'diff-unhandled-changes)
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893 (add-hook 'after-change-functions 'diff-after-change-function nil t)
894 (add-hook 'post-command-hook 'diff-post-command-hook nil t))
610a6418 895 ;; Neat trick from Dave Love to add more bindings in read-only mode:
fef8c55b 896 (add-to-list (make-local-variable 'minor-mode-overriding-map-alist)
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897 (cons 'buffer-read-only diff-mode-shared-map))
898 ;; add-log support
899 (set (make-local-variable 'add-log-current-defun-function)
900 'diff-current-defun)
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901 (set (make-local-variable 'add-log-buffer-file-name-function)
902 'diff-find-file-name))
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903
904;;;###autoload
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905(define-minor-mode diff-minor-mode
906 "Minor mode for viewing/editing context diffs.
907\\{diff-minor-mode-map}"
908 nil " Diff" nil
909 ;; FIXME: setup font-lock
fef8c55b 910 ;; setup change hooks
e8a1ed31 911 (if (not diff-update-on-the-fly)
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912 (add-hook 'write-contents-hooks 'diff-write-contents-hooks)
913 (make-local-variable 'diff-unhandled-changes)
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914 (add-hook 'after-change-functions 'diff-after-change-function nil t)
915 (add-hook 'post-command-hook 'diff-post-command-hook nil t)))
0b82e382 916
610a6418 917
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918;;;
919;;; Misc operations that have proved useful at some point.
920;;;
921
922(defun diff-next-complex-hunk ()
923 "Jump to the next \"complex\" hunk.
924\"Complex\" is approximated by \"the hunk changes the number of lines\".
925Only works for unified diffs."
926 (interactive)
927 (while
928 (and (re-search-forward "^@@ [-0-9]+,\\([0-9]+\\) [+0-9]+,\\([0-9]+\\) @@"
929 nil t)
930 (equal (match-string 1) (match-string 2)))))
931
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932(defun diff-hunk-text (hunk destp char-offset)
933 "Return the literal source text from HUNK as (TEXT . OFFSET).
934if DESTP is nil TEXT is the source, otherwise the destination text.
935CHAR-OFFSET is a char-offset in HUNK, and OFFSET is the corresponding
936char-offset in TEXT."
3017133f 937 (with-temp-buffer
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938 (insert hunk)
939 (goto-char (point-min))
940 (let ((src-pos nil)
941 (dst-pos nil)
942 (divider-pos nil)
943 (num-pfx-chars 2))
944 ;; Set the following variables:
945 ;; SRC-POS buffer pos of the source part of the hunk or nil if none
946 ;; DST-POS buffer pos of the destination part of the hunk or nil
947 ;; DIVIDER-POS buffer pos of any divider line separating the src & dst
948 ;; NUM-PFX-CHARS number of line-prefix characters used by this format"
949 (cond ((looking-at "^@@")
950 ;; unified diff
951 (setq num-pfx-chars 1)
952 (forward-line 1)
953 (setq src-pos (point) dst-pos (point)))
954 ((looking-at "^\\*\\*")
955 ;; context diff
956 (forward-line 2)
957 (setq src-pos (point))
958 (re-search-forward "^--- " nil t)
959 (forward-line 0)
960 (setq divider-pos (point))
961 (forward-line 1)
962 (setq dst-pos (point)))
963 ((looking-at "^[0-9]+a[0-9,]+$")
964 ;; normal diff, insert
965 (forward-line 1)
966 (setq dst-pos (point)))
967 ((looking-at "^[0-9,]+d[0-9]+$")
968 ;; normal diff, delete
969 (forward-line 1)
970 (setq src-pos (point)))
971 ((looking-at "^[0-9,]+c[0-9,]+$")
972 ;; normal diff, change
973 (forward-line 1)
974 (setq src-pos (point))
975 (re-search-forward "^---$" nil t)
976 (forward-line 0)
977 (setq divider-pos (point))
978 (forward-line 1)
979 (setq dst-pos (point)))
980 (t
981 (error "Unknown diff hunk type")))
982
983 (if (if destp (null dst-pos) (null src-pos))
984 ;; Implied empty text
985 (if char-offset '("" . 0) "")
986
987 ;; For context diffs, either side can be empty, (if there's only
988 ;; added or only removed text). We should then use the other side.
989 (cond ((equal src-pos divider-pos) (setq src-pos dst-pos))
990 ((equal dst-pos (point-max)) (setq dst-pos src-pos)))
991
992 (when char-offset (goto-char (+ (point-min) char-offset)))
993
994 ;; Get rid of anything except the desired text.
995 (save-excursion
996 ;; Delete unused text region
997 (let ((keep (if destp dst-pos src-pos)))
998 (when (and divider-pos (> divider-pos keep))
999 (delete-region divider-pos (point-max)))
1000 (delete-region (point-min) keep))
1001 ;; Remove line-prefix characters, and unneeded lines (unified diffs).
1002 (let ((kill-char (if destp ?- ?+)))
1003 (goto-char (point-min))
1004 (while (not (eobp))
1005 (if (eq (char-after) kill-char)
1006 (delete-region (point) (progn (forward-line 1) (point)))
1007 (delete-char num-pfx-chars)
1008 (forward-line 1)))))
1009
1010 (let ((text (buffer-substring-no-properties (point-min) (point-max))))
1011 (if char-offset (cons text (- (point) (point-min))) text))))))
370d860c 1012
7530b6da 1013
c0aa75f7 1014(defun diff-find-text (text)
1eabc5e6 1015 "Return the buffer position (BEG . END) of the nearest occurrence of TEXT.
7530b6da 1016If TEXT isn't found, nil is returned."
7530b6da
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1017 (let* ((orig (point))
1018 (forw (and (search-forward text nil t)
1eabc5e6 1019 (cons (match-beginning 0) (match-end 0))))
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1020 (back (and (goto-char (+ orig (length text)))
1021 (search-backward text nil t)
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1022 (cons (match-beginning 0) (match-end 0)))))
1023 ;; Choose the closest match.
1024 (if (and forw back)
1025 (if (> (- (car forw) orig) (- orig (car back))) back forw)
1026 (or back forw))))
1027
1028(defun diff-find-approx-text (text)
1029 "Return the buffer position (BEG . END) of the nearest occurrence of TEXT.
1030Whitespace differences are ignored."
1031 (let* ((orig (point))
1032 (re (concat "^[ \t\n\f]*"
1033 (mapconcat 'regexp-quote (split-string text) "[ \t\n\f]+")
1034 "[ \t\n\f]*\n"))
1035 (forw (and (re-search-forward re nil t)
1036 (cons (match-beginning 0) (match-end 0))))
1037 (back (and (goto-char (+ orig (length text)))
1038 (re-search-backward re nil t)
1039 (cons (match-beginning 0) (match-end 0)))))
1040 ;; Choose the closest match.
7530b6da 1041 (if (and forw back)
1eabc5e6 1042 (if (> (- (car forw) orig) (- orig (car back))) back forw)
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1043 (or back forw))))
1044
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1045(defsubst diff-xor (a b) (if a (not b) b))
1046
d868b3bd 1047(defun diff-find-source-location (&optional other-file reverse)
1eabc5e6
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1048 "Find out (BUF LINE-OFFSET POS SRC DST SWITCHED).
1049BUF is the buffer corresponding to the source file.
1050LINE-OFFSET is the offset between the expected and actual positions
1051 of the text of the hunk or nil if the text was not found.
1052POS is a pair (BEG . END) indicating the position of the text in the buffer.
1053SRC and DST are the two variants of text as returned by `diff-hunk-text'.
1054 SRC is the variant that was found in the buffer.
1055SWITCHED is non-nil if the patch is already applied."
7b91e0f2 1056 (save-excursion
e8a1ed31 1057 (let* ((other (diff-xor other-file diff-jump-to-old-file))
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1058 (char-offset (- (point) (progn (diff-beginning-of-hunk) (point))))
1059 (hunk (buffer-substring (point)
1060 (save-excursion (diff-end-of-hunk) (point))))
1061 (old (diff-hunk-text hunk reverse char-offset))
1062 (new (diff-hunk-text hunk (not reverse) char-offset))
7b91e0f2 1063 ;; Find the location specification.
d868b3bd 1064 (line (if (not (looking-at "\\(?:\\*\\{15\\}.*\n\\)?[-@* ]*\\([0-9,]+\\)\\([ acd+]+\\([0-9,]+\\)\\)?"))
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1065 (error "Can't find the hunk header")
1066 (if other (match-string 1)
1067 (if (match-end 3) (match-string 3)
1068 (unless (re-search-forward "^--- \\([0-9,]+\\)" nil t)
1069 (error "Can't find the hunk separator"))
1070 (match-string 1)))))
1071 (file (or (diff-find-file-name other) (error "Can't find the file")))
1072 (buf (find-file-noselect file)))
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SM
1073 ;; Update the user preference if he so wished.
1074 (when (> (prefix-numeric-value other-file) 8)
e8a1ed31 1075 (setq diff-jump-to-old-file other))
d868b3bd
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1076 (with-current-buffer buf
1077 (goto-line (string-to-number line))
1078 (let* ((orig-pos (point))
1eabc5e6
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1079 (switched nil)
1080 (pos (or (diff-find-text (car old))
1081 (progn (setq switched t) (diff-find-text (car new)))
1082 (progn (setq switched nil)
1083 (diff-find-approx-text (car old)))
1084 (progn (setq switched t)
1085 (diff-find-approx-text (car new)))
1086 (progn (setq switched nil) nil))))
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1087 (nconc
1088 (list buf)
1eabc5e6
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1089 (if pos
1090 (list (count-lines orig-pos (car pos)) pos)
1091 (list nil (cons orig-pos (+ orig-pos (length (car old))))))
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1092 (if switched (list new old t) (list old new))))))))
1093
7b91e0f2 1094
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1095(defun diff-hunk-status-msg (line-offset reversed dry-run)
1096 (let ((msg (if dry-run
1097 (if reversed "already applied" "not yet applied")
1098 (if reversed "undone" "applied"))))
1099 (message (cond ((null line-offset) "Hunk text not found")
1100 ((= line-offset 0) "Hunk %s")
1101 ((= line-offset 1) "Hunk %s at offset %d line")
1102 (t "Hunk %s at offset %d lines"))
1103 msg line-offset)))
1104
1105
1106(defun diff-apply-hunk (&optional reverse)
6e4e8a3b 1107 "Apply the current hunk to the source file and go to the next.
7530b6da 1108By default, the new source file is patched, but if the variable
e8a1ed31 1109`diff-jump-to-old-file' is non-nil, then the old source file is
7530b6da
MB
1110patched instead (some commands, such as `diff-goto-source' can change
1111the value of this variable when given an appropriate prefix argument).
1112
4eaa6852 1113With a prefix argument, REVERSE the hunk."
370d860c 1114 (interactive "P")
281096ed 1115 (destructuring-bind (buf line-offset pos old new &optional switched)
370d860c
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1116 (diff-find-source-location nil reverse)
1117 (cond
4eaa6852
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1118 ((null line-offset)
1119 (error "Can't find the text to patch"))
370d860c 1120 ((and switched
cdbb79c1 1121 ;; A reversed patch was detected, perhaps apply it in reverse.
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1122 (not (save-window-excursion
1123 (pop-to-buffer buf)
1eabc5e6 1124 (goto-char (+ (car pos) (cdr old)))
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1125 (y-or-n-p
1126 (if reverse
1127 "Hunk hasn't been applied yet; apply it now? "
1128 "Hunk has already been applied; undo it? ")))))
4eaa6852 1129 (message "(Nothing done)"))
370d860c 1130 (t
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1131 ;; Apply the hunk
1132 (with-current-buffer buf
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1133 (goto-char (car pos))
1134 (delete-region (car pos) (cdr pos))
4eaa6852
MB
1135 (insert (car new)))
1136 ;; Display BUF in a window
1eabc5e6 1137 (set-window-point (display-buffer buf) (+ (car pos) (cdr new)))
4eaa6852
MB
1138 (diff-hunk-status-msg line-offset (diff-xor switched reverse) nil)
1139 (when diff-advance-after-apply-hunk
1140 (diff-hunk-next))))))
370d860c 1141
7530b6da 1142
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MB
1143(defun diff-test-hunk (&optional reverse)
1144 "See whether it's possible to apply the current hunk.
4eaa6852 1145With a prefix argument, try to REVERSE the hunk."
7530b6da 1146 (interactive "P")
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1147 (destructuring-bind (buf line-offset pos src dst &optional switched)
1148 (diff-find-source-location nil reverse)
1eabc5e6 1149 (set-window-point (display-buffer buf) (+ (car pos) (cdr src)))
4eaa6852 1150 (diff-hunk-status-msg line-offset (diff-xor reverse switched) t)))
370d860c 1151
7530b6da
MB
1152
1153(defun diff-goto-source (&optional other-file)
1154 "Jump to the corresponding source line.
e8a1ed31 1155`diff-jump-to-old-file' (or its opposite if the OTHER-FILE prefix arg
281096ed 1156is given) determines whether to jump to the old or the new file.
7530b6da 1157If the prefix arg is bigger than 8 (for example with \\[universal-argument] \\[universal-argument])
e8a1ed31 1158 then `diff-jump-to-old-file' is also set, for the next invocations."
7530b6da 1159 (interactive "P")
a6373340
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1160 ;; When pointing at a removal line, we probably want to jump to
1161 ;; the old location, and else to the new (i.e. as if reverting).
1162 ;; This is a convenient detail when using smerge-diff.
1163 (let ((rev (not (save-excursion (beginning-of-line) (looking-at "[-<]")))))
1164 (destructuring-bind (buf line-offset pos src dst &optional switched)
1165 (diff-find-source-location other-file rev)
1166 (pop-to-buffer buf)
1eabc5e6 1167 (goto-char (+ (car pos) (cdr src)))
55d5d717 1168 (diff-hunk-status-msg line-offset (diff-xor rev switched) t))))
370d860c 1169
7530b6da 1170
281096ed 1171(defun diff-current-defun ()
370d860c
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1172 "Find the name of function at point.
1173For use in `add-log-current-defun-function'."
281096ed
SM
1174 (destructuring-bind (buf line-offset pos src dst &optional switched)
1175 (diff-find-source-location)
1176 (save-excursion
1177 (beginning-of-line)
1178 (or (when (memq (char-after) '(?< ?-))
370d860c
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1179 ;; Cursor is pointing at removed text. This could be a removed
1180 ;; function, in which case, going to the source buffer will
1181 ;; not help since the function is now removed. Instead,
1182 ;; try to figure out the function name just from the code-fragment.
281096ed
SM
1183 (let ((old (if switched dst src)))
1184 (with-temp-buffer
1185 (insert (car old))
1186 (goto-char (cdr old))
1187 (funcall (with-current-buffer buf major-mode))
1188 (add-log-current-defun))))
1189 (with-current-buffer buf
1eabc5e6 1190 (goto-char (+ (car pos) (cdr src)))
281096ed 1191 (add-log-current-defun))))))
027ac3f8 1192
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1193;; provide the package
1194(provide 'diff-mode)
1195
027ac3f8 1196;;; Old Change Log from when diff-mode wasn't part of Emacs:
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1197;; Revision 1.11 1999/10/09 23:38:29 monnier
1198;; (diff-mode-load-hook): dropped.
1199;; (auto-mode-alist): also catch *.diffs.
1200;; (diff-find-file-name, diff-mode): add smarts to find the right file
1201;; for *.rej files (that lack any file name indication).
1202;;
1203;; Revision 1.10 1999/09/30 15:32:11 monnier
1204;; added support for "\ No newline at end of file".
1205;;
1206;; Revision 1.9 1999/09/15 00:01:13 monnier
1207;; - added basic `compile' support.
1208;; - have diff-kill-hunk call diff-kill-file if it's the only hunk.
1209;; - diff-kill-file now tries to kill the leading garbage as well.
1210;;
1211;; Revision 1.8 1999/09/13 21:10:09 monnier
1212;; - don't use CL in the autoloaded code
1213;; - accept diffs using -T
1214;;
1215;; Revision 1.7 1999/09/05 20:53:03 monnier
1216;; interface to ediff-patch
1217;;
1218;; Revision 1.6 1999/09/01 20:55:13 monnier
1219;; (ediff=patch-file): add bindings to call ediff-patch.
1220;; (diff-find-file-name): taken out of diff-goto-source.
1221;; (diff-unified->context, diff-context->unified, diff-reverse-direction,
1222;; diff-fixup-modifs): only use the region if a prefix arg is given.
1223;;
1224;; Revision 1.5 1999/08/31 19:18:52 monnier
1225;; (diff-beginning-of-file, diff-prev-file): fixed wrong parenthesis.
1226;;
1227;; Revision 1.4 1999/08/31 13:01:44 monnier
1228;; use `combine-after-change-calls' to minimize the slowdown of font-lock.
1229;;
1230
1231;;; diff-mode.el ends here