* Makefile.in (install-arch-indep): Avoid readdir race.
[emacs.git] / lisp / vc / diff-mode.el
blob923de9a0ca6261cd6f2e38c61ac50f158343e334
1 ;;; diff-mode.el --- a mode for viewing/editing context diffs -*- lexical-binding: t -*-
3 ;; Copyright (C) 1998-2014 Free Software Foundation, Inc.
5 ;; Author: Stefan Monnier <monnier@iro.umontreal.ca>
6 ;; Keywords: convenience patch diff vc
8 ;; This file is part of GNU Emacs.
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 3 of the License, or
13 ;; (at your option) any later version.
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.
20 ;; You should have received a copy of the GNU General Public License
21 ;; along with GNU Emacs. If not, see <http://www.gnu.org/licenses/>.
23 ;;; Commentary:
25 ;; Provides support for font-lock, outline, navigation
26 ;; commands, editing and various conversions as well as jumping
27 ;; to the corresponding source file.
29 ;; Inspired by Pavel Machek's patch-mode.el (<pavel@@atrey.karlin.mff.cuni.cz>)
30 ;; Some efforts were spent to have it somewhat compatible with XEmacs's
31 ;; diff-mode as well as with compilation-minor-mode
33 ;; Bugs:
35 ;; - Reverse doesn't work with normal diffs.
37 ;; Todo:
39 ;; - Improve `diff-add-change-log-entries-other-window',
40 ;; it is very simplistic now.
42 ;; - Add a `delete-after-apply' so C-c C-a automatically deletes hunks.
43 ;; Also allow C-c C-a to delete already-applied hunks.
45 ;; - Try `diff <file> <hunk>' to try and fuzzily discover the source location
46 ;; of a hunk. Show then the changes between <file> and <hunk> and make it
47 ;; possible to apply them to <file>, <hunk-src>, or <hunk-dst>.
48 ;; Or maybe just make it into a ".rej to diff3-markers converter".
49 ;; Maybe just use `wiggle' (by Neil Brown) to do it for us.
51 ;; - in diff-apply-hunk, strip context in replace-match to better
52 ;; preserve markers and spacing.
53 ;; - Handle `diff -b' output in context->unified.
55 ;;; Code:
56 (eval-when-compile (require 'cl-lib))
58 (defvar add-log-buffer-file-name-function)
61 (defgroup diff-mode ()
62 "Major mode for viewing/editing diffs."
63 :version "21.1"
64 :group 'tools
65 :group 'diff)
67 (defcustom diff-default-read-only nil
68 "If non-nil, `diff-mode' buffers default to being read-only."
69 :type 'boolean
70 :group 'diff-mode)
72 (defcustom diff-jump-to-old-file nil
73 "Non-nil means `diff-goto-source' jumps to the old file.
74 Else, it jumps to the new file."
75 :type 'boolean
76 :group 'diff-mode)
78 (defcustom diff-update-on-the-fly t
79 "Non-nil means hunk headers are kept up-to-date on-the-fly.
80 When editing a diff file, the line numbers in the hunk headers
81 need to be kept consistent with the actual diff. This can
82 either be done on the fly (but this sometimes interacts poorly with the
83 undo mechanism) or whenever the file is written (can be slow
84 when editing big diffs)."
85 :type 'boolean
86 :group 'diff-mode)
88 (defcustom diff-advance-after-apply-hunk t
89 "Non-nil means `diff-apply-hunk' will move to the next hunk after applying."
90 :type 'boolean
91 :group 'diff-mode)
93 (defcustom diff-mode-hook nil
94 "Run after setting up the `diff-mode' major mode."
95 :type 'hook
96 :options '(diff-delete-empty-files diff-make-unified)
97 :group 'diff-mode)
99 (defvar diff-vc-backend nil
100 "The VC backend that created the current Diff buffer, if any.")
102 (defvar diff-outline-regexp
103 "\\([*+][*+][*+] [^0-9]\\|@@ ...\\|\\*\\*\\* [0-9].\\|--- [0-9]..\\)")
105 ;;;;
106 ;;;; keymap, menu, ...
107 ;;;;
109 (easy-mmode-defmap diff-mode-shared-map
110 '(("n" . diff-hunk-next)
111 ("N" . diff-file-next)
112 ("p" . diff-hunk-prev)
113 ("P" . diff-file-prev)
114 ("\t" . diff-hunk-next)
115 ([backtab] . diff-hunk-prev)
116 ("k" . diff-hunk-kill)
117 ("K" . diff-file-kill)
118 ("}" . diff-file-next) ; From compilation-minor-mode.
119 ("{" . diff-file-prev)
120 ("\C-m" . diff-goto-source)
121 ([mouse-2] . diff-goto-source)
122 ("W" . widen)
123 ("o" . diff-goto-source) ; other-window
124 ("A" . diff-ediff-patch)
125 ("r" . diff-restrict-view)
126 ("R" . diff-reverse-direction)
127 ([remap undo] . diff-undo))
128 "Basic keymap for `diff-mode', bound to various prefix keys."
129 :inherit special-mode-map)
131 (easy-mmode-defmap diff-mode-map
132 `(("\e" . ,(let ((map (make-sparse-keymap)))
133 ;; We want to inherit most bindings from diff-mode-shared-map,
134 ;; but not all since they may hide useful M-<foo> global
135 ;; bindings when editing.
136 (set-keymap-parent map diff-mode-shared-map)
137 (dolist (key '("A" "r" "R" "g" "q" "W" "z"))
138 (define-key map key nil))
139 map))
140 ;; From compilation-minor-mode.
141 ("\C-c\C-c" . diff-goto-source)
142 ;; By analogy with the global C-x 4 a binding.
143 ("\C-x4A" . diff-add-change-log-entries-other-window)
144 ;; Misc operations.
145 ("\C-c\C-a" . diff-apply-hunk)
146 ("\C-c\C-e" . diff-ediff-patch)
147 ("\C-c\C-n" . diff-restrict-view)
148 ("\C-c\C-s" . diff-split-hunk)
149 ("\C-c\C-t" . diff-test-hunk)
150 ("\C-c\C-r" . diff-reverse-direction)
151 ("\C-c\C-u" . diff-context->unified)
152 ;; `d' because it duplicates the context :-( --Stef
153 ("\C-c\C-d" . diff-unified->context)
154 ("\C-c\C-w" . diff-ignore-whitespace-hunk)
155 ("\C-c\C-b" . diff-refine-hunk) ;No reason for `b' :-(
156 ("\C-c\C-f" . next-error-follow-minor-mode))
157 "Keymap for `diff-mode'. See also `diff-mode-shared-map'.")
159 (easy-menu-define diff-mode-menu diff-mode-map
160 "Menu for `diff-mode'."
161 '("Diff"
162 ["Jump to Source" diff-goto-source
163 :help "Jump to the corresponding source line"]
164 ["Apply hunk" diff-apply-hunk
165 :help "Apply the current hunk to the source file and go to the next"]
166 ["Test applying hunk" diff-test-hunk
167 :help "See whether it's possible to apply the current hunk"]
168 ["Apply diff with Ediff" diff-ediff-patch
169 :help "Call `ediff-patch-file' on the current buffer"]
170 ["Create Change Log entries" diff-add-change-log-entries-other-window
171 :help "Create ChangeLog entries for the changes in the diff buffer"]
172 "-----"
173 ["Reverse direction" diff-reverse-direction
174 :help "Reverse the direction of the diffs"]
175 ["Context -> Unified" diff-context->unified
176 :help "Convert context diffs to unified diffs"]
177 ["Unified -> Context" diff-unified->context
178 :help "Convert unified diffs to context diffs"]
179 ;;["Fixup Headers" diff-fixup-modifs (not buffer-read-only)]
180 ["Remove trailing whitespace" diff-delete-trailing-whitespace
181 :help "Remove trailing whitespace problems introduced by the diff"]
182 ["Show trailing whitespace" whitespace-mode
183 :style toggle :selected (bound-and-true-p whitespace-mode)
184 :help "Show trailing whitespace in modified lines"]
185 "-----"
186 ["Split hunk" diff-split-hunk
187 :active (diff-splittable-p)
188 :help "Split the current (unified diff) hunk at point into two hunks"]
189 ["Ignore whitespace changes" diff-ignore-whitespace-hunk
190 :help "Re-diff the current hunk, ignoring whitespace differences"]
191 ["Highlight fine changes" diff-refine-hunk
192 :help "Highlight changes of hunk at point at a finer granularity"]
193 ["Kill current hunk" diff-hunk-kill
194 :help "Kill current hunk"]
195 ["Kill current file's hunks" diff-file-kill
196 :help "Kill all current file's hunks"]
197 "-----"
198 ["Previous Hunk" diff-hunk-prev
199 :help "Go to the previous count'th hunk"]
200 ["Next Hunk" diff-hunk-next
201 :help "Go to the next count'th hunk"]
202 ["Previous File" diff-file-prev
203 :help "Go to the previous count'th file"]
204 ["Next File" diff-file-next
205 :help "Go to the next count'th file"]
208 (defcustom diff-minor-mode-prefix "\C-c="
209 "Prefix key for `diff-minor-mode' commands."
210 :type '(choice (string "\e") (string "C-c=") string)
211 :group 'diff-mode)
213 (easy-mmode-defmap diff-minor-mode-map
214 `((,diff-minor-mode-prefix . ,diff-mode-shared-map))
215 "Keymap for `diff-minor-mode'. See also `diff-mode-shared-map'.")
217 (define-minor-mode diff-auto-refine-mode
218 "Toggle automatic diff hunk highlighting (Diff Auto Refine mode).
219 With a prefix argument ARG, enable Diff Auto Refine mode if ARG
220 is positive, and disable it otherwise. If called from Lisp,
221 enable the mode if ARG is omitted or nil.
223 Diff Auto Refine mode is a buffer-local minor mode used with
224 `diff-mode'. When enabled, Emacs automatically highlights
225 changes in detail as the user visits hunks. When transitioning
226 from disabled to enabled, it tries to refine the current hunk, as
227 well."
228 :group 'diff-mode :init-value t :lighter nil ;; " Auto-Refine"
229 (when diff-auto-refine-mode
230 (condition-case-unless-debug nil (diff-refine-hunk) (error nil))))
232 ;;;;
233 ;;;; font-lock support
234 ;;;;
236 (defface diff-header
237 '((((class color) (min-colors 88) (background light))
238 :background "grey80")
239 (((class color) (min-colors 88) (background dark))
240 :background "grey45")
241 (((class color))
242 :foreground "blue1" :weight bold)
243 (t :weight bold))
244 "`diff-mode' face inherited by hunk and index header faces."
245 :group 'diff-mode)
246 (define-obsolete-face-alias 'diff-header-face 'diff-header "22.1")
247 (defvar diff-header-face 'diff-header)
249 (defface diff-file-header
250 '((((class color) (min-colors 88) (background light))
251 :background "grey70" :weight bold)
252 (((class color) (min-colors 88) (background dark))
253 :background "grey60" :weight bold)
254 (((class color))
255 :foreground "cyan" :weight bold)
256 (t :weight bold)) ; :height 1.3
257 "`diff-mode' face used to highlight file header lines."
258 :group 'diff-mode)
259 (define-obsolete-face-alias 'diff-file-header-face 'diff-file-header "22.1")
260 (defvar diff-file-header-face 'diff-file-header)
262 (defface diff-index
263 '((t :inherit diff-file-header))
264 "`diff-mode' face used to highlight index header lines."
265 :group 'diff-mode)
266 (define-obsolete-face-alias 'diff-index-face 'diff-index "22.1")
267 (defvar diff-index-face 'diff-index)
269 (defface diff-hunk-header
270 '((t :inherit diff-header))
271 "`diff-mode' face used to highlight hunk header lines."
272 :group 'diff-mode)
273 (define-obsolete-face-alias 'diff-hunk-header-face 'diff-hunk-header "22.1")
274 (defvar diff-hunk-header-face 'diff-hunk-header)
276 (defface diff-removed
277 '((default
278 :inherit diff-changed)
279 (((class color) (min-colors 88) (background light))
280 :background "#ffdddd")
281 (((class color) (min-colors 88) (background dark))
282 :background "#553333")
283 (((class color))
284 :foreground "red"))
285 "`diff-mode' face used to highlight removed lines."
286 :group 'diff-mode)
287 (define-obsolete-face-alias 'diff-removed-face 'diff-removed "22.1")
288 (defvar diff-removed-face 'diff-removed)
290 (defface diff-added
291 '((default
292 :inherit diff-changed)
293 (((class color) (min-colors 88) (background light))
294 :background "#ddffdd")
295 (((class color) (min-colors 88) (background dark))
296 :background "#335533")
297 (((class color))
298 :foreground "green"))
299 "`diff-mode' face used to highlight added lines."
300 :group 'diff-mode)
301 (define-obsolete-face-alias 'diff-added-face 'diff-added "22.1")
302 (defvar diff-added-face 'diff-added)
304 (defface diff-changed
305 ;; We normally apply a `shadow'-based face on the `diff-context'
306 ;; face, and keep `diff-changed' the default.
307 '((((class color grayscale) (min-colors 88)))
308 ;; If the terminal lacks sufficient colors for shadowing,
309 ;; highlight changed lines explicitly.
310 (((class color))
311 :foreground "yellow"))
312 "`diff-mode' face used to highlight changed lines."
313 :group 'diff-mode)
314 (define-obsolete-face-alias 'diff-changed-face 'diff-changed "22.1")
315 (defvar diff-changed-face 'diff-changed)
317 (defface diff-indicator-removed
318 '((t :inherit diff-removed))
319 "`diff-mode' face used to highlight indicator of removed lines (-, <)."
320 :group 'diff-mode
321 :version "22.1")
322 (defvar diff-indicator-removed-face 'diff-indicator-removed)
324 (defface diff-indicator-added
325 '((t :inherit diff-added))
326 "`diff-mode' face used to highlight indicator of added lines (+, >)."
327 :group 'diff-mode
328 :version "22.1")
329 (defvar diff-indicator-added-face 'diff-indicator-added)
331 (defface diff-indicator-changed
332 '((t :inherit diff-changed))
333 "`diff-mode' face used to highlight indicator of changed lines."
334 :group 'diff-mode
335 :version "22.1")
336 (defvar diff-indicator-changed-face 'diff-indicator-changed)
338 (defface diff-function
339 '((t :inherit diff-header))
340 "`diff-mode' face used to highlight function names produced by \"diff -p\"."
341 :group 'diff-mode)
342 (define-obsolete-face-alias 'diff-function-face 'diff-function "22.1")
343 (defvar diff-function-face 'diff-function)
345 (defface diff-context
346 '((((class color grayscale) (min-colors 88)) :inherit shadow))
347 "`diff-mode' face used to highlight context and other side-information."
348 :group 'diff-mode)
349 (define-obsolete-face-alias 'diff-context-face 'diff-context "22.1")
350 (defvar diff-context-face 'diff-context)
352 (defface diff-nonexistent
353 '((t :inherit diff-file-header))
354 "`diff-mode' face used to highlight nonexistent files in recursive diffs."
355 :group 'diff-mode)
356 (define-obsolete-face-alias 'diff-nonexistent-face 'diff-nonexistent "22.1")
357 (defvar diff-nonexistent-face 'diff-nonexistent)
359 (defconst diff-yank-handler '(diff-yank-function))
360 (defun diff-yank-function (text)
361 ;; FIXME: the yank-handler is now called separately on each piece of text
362 ;; with a yank-handler property, so the next-single-property-change call
363 ;; below will always return nil :-( --stef
364 (let ((mixed (next-single-property-change 0 'yank-handler text))
365 (start (point)))
366 ;; First insert the text.
367 (insert text)
368 ;; If the text does not include any diff markers and if we're not
369 ;; yanking back into a diff-mode buffer, get rid of the prefixes.
370 (unless (or mixed (derived-mode-p 'diff-mode))
371 (undo-boundary) ; Just in case the user wanted the prefixes.
372 (let ((re (save-excursion
373 (if (re-search-backward "^[><!][ \t]" start t)
374 (if (eq (char-after) ?!)
375 "^[!+- ][ \t]" "^[<>][ \t]")
376 "^[ <>!+-]"))))
377 (save-excursion
378 (while (re-search-backward re start t)
379 (replace-match "" t t)))))))
381 (defconst diff-hunk-header-re-unified
382 "^@@ -\\([0-9]+\\)\\(?:,\\([0-9]+\\)\\)? \\+\\([0-9]+\\)\\(?:,\\([0-9]+\\)\\)? @@")
383 (defconst diff-context-mid-hunk-header-re
384 "--- \\([0-9]+\\)\\(?:,\\([0-9]+\\)\\)? ----$")
386 (defvar diff-use-changed-face (and (face-differs-from-default-p diff-changed-face)
387 (not (face-equal diff-changed-face diff-added-face))
388 (not (face-equal diff-changed-face diff-removed-face)))
389 "If non-nil, use the face `diff-changed' for changed lines in context diffs.
390 Otherwise, use the face `diff-removed' for removed lines,
391 and the face `diff-added' for added lines.")
393 (defvar diff-font-lock-keywords
394 `((,(concat "\\(" diff-hunk-header-re-unified "\\)\\(.*\\)$")
395 (1 diff-hunk-header-face) (6 diff-function-face))
396 ("^\\(\\*\\{15\\}\\)\\(.*\\)$" ;context
397 (1 diff-hunk-header-face) (2 diff-function-face))
398 ("^\\*\\*\\* .+ \\*\\*\\*\\*". diff-hunk-header-face) ;context
399 (,diff-context-mid-hunk-header-re . diff-hunk-header-face) ;context
400 ("^[0-9,]+[acd][0-9,]+$" . diff-hunk-header-face) ;normal
401 ("^---$" . diff-hunk-header-face) ;normal
402 ;; For file headers, accept files with spaces, but be careful to rule
403 ;; out false-positives when matching hunk headers.
404 ("^\\(---\\|\\+\\+\\+\\|\\*\\*\\*\\) \\([^\t\n]+?\\)\\(?:\t.*\\| \\(\\*\\*\\*\\*\\|----\\)\\)?\n"
405 (0 diff-header-face)
406 (2 (if (not (match-end 3)) diff-file-header-face) prepend))
407 ("^\\([-<]\\)\\(.*\n\\)"
408 (1 diff-indicator-removed-face) (2 diff-removed-face))
409 ("^\\([+>]\\)\\(.*\n\\)"
410 (1 diff-indicator-added-face) (2 diff-added-face))
411 ("^\\(!\\)\\(.*\n\\)"
412 (1 (if diff-use-changed-face
413 diff-indicator-changed-face
414 ;; Otherwise, search for `diff-context-mid-hunk-header-re' and
415 ;; if the line of context diff is above, use `diff-removed-face';
416 ;; if below, use `diff-added-face'.
417 (save-match-data
418 (let ((limit (save-excursion (diff-beginning-of-hunk))))
419 (if (save-excursion (re-search-backward diff-context-mid-hunk-header-re limit t))
420 diff-indicator-added-face
421 diff-indicator-removed-face)))))
422 (2 (if diff-use-changed-face
423 diff-changed-face
424 ;; Otherwise, use the same method as above.
425 (save-match-data
426 (let ((limit (save-excursion (diff-beginning-of-hunk))))
427 (if (save-excursion (re-search-backward diff-context-mid-hunk-header-re limit t))
428 diff-added-face
429 diff-removed-face))))))
430 ("^\\(?:Index\\|revno\\): \\(.+\\).*\n"
431 (0 diff-header-face) (1 diff-index-face prepend))
432 ("^Only in .*\n" . diff-nonexistent-face)
433 ("^\\(#\\)\\(.*\\)"
434 (1 font-lock-comment-delimiter-face)
435 (2 font-lock-comment-face))
436 ("^[^-=+*!<>#].*\n" (0 diff-context-face))))
438 (defconst diff-font-lock-defaults
439 '(diff-font-lock-keywords t nil nil nil (font-lock-multiline . nil)))
441 (defvar diff-imenu-generic-expression
442 ;; Prefer second name as first is most likely to be a backup or
443 ;; version-control name. The [\t\n] at the end of the unidiff pattern
444 ;; catches Debian source diff files (which lack the trailing date).
445 '((nil "\\+\\+\\+\\ \\([^\t\n]+\\)[\t\n]" 1) ; unidiffs
446 (nil "^--- \\([^\t\n]+\\)\t.*\n\\*" 1))) ; context diffs
448 ;;;;
449 ;;;; Movement
450 ;;;;
452 (defvar diff-valid-unified-empty-line t
453 "If non-nil, empty lines are valid in unified diffs.
454 Some versions of diff replace all-blank context lines in unified format with
455 empty lines. This makes the format less robust, but is tolerated.
456 See http://lists.gnu.org/archive/html/emacs-devel/2007-11/msg01990.html")
458 (defconst diff-hunk-header-re
459 (concat "^\\(?:" diff-hunk-header-re-unified ".*\\|\\*\\{15\\}.*\n\\*\\*\\* .+ \\*\\*\\*\\*\\|[0-9]+\\(,[0-9]+\\)?[acd][0-9]+\\(,[0-9]+\\)?\\)$"))
460 (defconst diff-file-header-re (concat "^\\(--- .+\n\\+\\+\\+ \\|\\*\\*\\* .+\n--- \\|[^-+!<>0-9@* \n]\\).+\n" (substring diff-hunk-header-re 1)))
461 (defvar diff-narrowed-to nil)
463 (defun diff-hunk-style (&optional style)
464 (when (looking-at diff-hunk-header-re)
465 (setq style (cdr (assq (char-after) '((?@ . unified) (?* . context)))))
466 (goto-char (match-end 0)))
467 style)
469 (defun diff-end-of-hunk (&optional style donttrustheader)
470 "Advance to the end of the current hunk, and return its position."
471 (let (end)
472 (when (looking-at diff-hunk-header-re)
473 ;; Especially important for unified (because headers are ambiguous).
474 (setq style (diff-hunk-style style))
475 (goto-char (match-end 0))
476 (when (and (not donttrustheader) (match-end 2))
477 (let* ((nold (string-to-number (or (match-string 2) "1")))
478 (nnew (string-to-number (or (match-string 4) "1")))
479 (endold
480 (save-excursion
481 (re-search-forward (if diff-valid-unified-empty-line
482 "^[- \n]" "^[- ]")
483 nil t nold)
484 (line-beginning-position
485 ;; Skip potential "\ No newline at end of file".
486 (if (looking-at ".*\n\\\\") 3 2))))
487 (endnew
488 ;; The hunk may end with a bunch of "+" lines, so the `end' is
489 ;; then further than computed above.
490 (save-excursion
491 (re-search-forward (if diff-valid-unified-empty-line
492 "^[+ \n]" "^[+ ]")
493 nil t nnew)
494 (line-beginning-position
495 ;; Skip potential "\ No newline at end of file".
496 (if (looking-at ".*\n\\\\") 3 2)))))
497 (setq end (max endold endnew)))))
498 ;; We may have a first evaluation of `end' thanks to the hunk header.
499 (unless end
500 (setq end (and (re-search-forward
501 (pcase style
502 (`unified
503 (concat (if diff-valid-unified-empty-line
504 "^[^-+# \\\n]\\|" "^[^-+# \\]\\|")
505 ;; A `unified' header is ambiguous.
506 diff-file-header-re))
507 (`context "^[^-+#! \\]")
508 (`normal "^[^<>#\\]")
509 (_ "^[^-+#!<> \\]"))
510 nil t)
511 (match-beginning 0)))
512 (when diff-valid-unified-empty-line
513 ;; While empty lines may be valid inside hunks, they are also likely
514 ;; to be unrelated to the hunk.
515 (goto-char (or end (point-max)))
516 (while (eq ?\n (char-before (1- (point))))
517 (forward-char -1)
518 (setq end (point)))))
519 ;; The return value is used by easy-mmode-define-navigation.
520 (goto-char (or end (point-max)))))
522 (defun diff-beginning-of-hunk (&optional try-harder)
523 "Move back to the previous hunk beginning, and return its position.
524 If point is in a file header rather than a hunk, advance to the
525 next hunk if TRY-HARDER is non-nil; otherwise signal an error."
526 (beginning-of-line)
527 (if (looking-at diff-hunk-header-re)
528 (point)
529 (forward-line 1)
530 (condition-case ()
531 (re-search-backward diff-hunk-header-re)
532 (error
533 (unless try-harder
534 (error "Can't find the beginning of the hunk"))
535 (diff-beginning-of-file-and-junk)
536 (diff-hunk-next)
537 (point)))))
539 (defun diff-unified-hunk-p ()
540 (save-excursion
541 (ignore-errors
542 (diff-beginning-of-hunk)
543 (looking-at "^@@"))))
545 (defun diff-beginning-of-file ()
546 (beginning-of-line)
547 (unless (looking-at diff-file-header-re)
548 (let ((start (point))
549 res)
550 ;; diff-file-header-re may need to match up to 4 lines, so in case
551 ;; we're inside the header, we need to move up to 3 lines forward.
552 (forward-line 3)
553 (if (and (setq res (re-search-backward diff-file-header-re nil t))
554 ;; Maybe the 3 lines forward were too much and we matched
555 ;; a file header after our starting point :-(
556 (or (<= (point) start)
557 (setq res (re-search-backward diff-file-header-re nil t))))
559 (goto-char start)
560 (error "Can't find the beginning of the file")))))
563 (defun diff-end-of-file ()
564 (re-search-forward "^[-+#!<>0-9@* \\]" nil t)
565 (re-search-forward (concat "^[^-+#!<>0-9@* \\]\\|" diff-file-header-re)
566 nil 'move)
567 (if (match-beginning 1)
568 (goto-char (match-beginning 1))
569 (beginning-of-line)))
571 (defvar diff--auto-refine-data nil)
573 ;; Define diff-{hunk,file}-{prev,next}
574 (easy-mmode-define-navigation
575 diff-hunk diff-hunk-header-re "hunk" diff-end-of-hunk diff-restrict-view
576 (when diff-auto-refine-mode
577 (unless (prog1 diff--auto-refine-data
578 (setq diff--auto-refine-data
579 (cons (current-buffer) (point-marker))))
580 (run-at-time 0.0 nil
581 (lambda ()
582 (when diff--auto-refine-data
583 (let ((buffer (car diff--auto-refine-data))
584 (point (cdr diff--auto-refine-data)))
585 (setq diff--auto-refine-data nil)
586 (with-local-quit
587 (when (buffer-live-p buffer)
588 (with-current-buffer buffer
589 (save-excursion
590 (goto-char point)
591 (diff-refine-hunk))))))))))))
593 (easy-mmode-define-navigation
594 diff-file diff-file-header-re "file" diff-end-of-file)
596 (defun diff-bounds-of-hunk ()
597 "Return the bounds of the diff hunk at point.
598 The return value is a list (BEG END), which are the hunk's start
599 and end positions. Signal an error if no hunk is found. If
600 point is in a file header, return the bounds of the next hunk."
601 (save-excursion
602 (let ((pos (point))
603 (beg (diff-beginning-of-hunk t))
604 (end (diff-end-of-hunk)))
605 (cond ((>= end pos)
606 (list beg end))
607 ;; If this hunk ends above POS, consider the next hunk.
608 ((re-search-forward diff-hunk-header-re nil t)
609 (list (match-beginning 0) (diff-end-of-hunk)))
610 (t (error "No hunk found"))))))
612 (defun diff-bounds-of-file ()
613 "Return the bounds of the file segment at point.
614 The return value is a list (BEG END), which are the segment's
615 start and end positions."
616 (save-excursion
617 (let ((pos (point))
618 (beg (progn (diff-beginning-of-file-and-junk)
619 (point))))
620 (diff-end-of-file)
621 ;; bzr puts a newline after the last hunk.
622 (while (looking-at "^\n")
623 (forward-char 1))
624 (if (> pos (point))
625 (error "Not inside a file diff"))
626 (list beg (point)))))
628 (defun diff-restrict-view (&optional arg)
629 "Restrict the view to the current hunk.
630 If the prefix ARG is given, restrict the view to the current file instead."
631 (interactive "P")
632 (apply 'narrow-to-region
633 (if arg (diff-bounds-of-file) (diff-bounds-of-hunk)))
634 (set (make-local-variable 'diff-narrowed-to) (if arg 'file 'hunk)))
636 (defun diff-hunk-kill ()
637 "Kill the hunk at point."
638 (interactive)
639 (let* ((hunk-bounds (diff-bounds-of-hunk))
640 (file-bounds (ignore-errors (diff-bounds-of-file)))
641 ;; If the current hunk is the only one for its file, kill the
642 ;; file header too.
643 (bounds (if (and file-bounds
644 (progn (goto-char (car file-bounds))
645 (= (progn (diff-hunk-next) (point))
646 (car hunk-bounds)))
647 (progn (goto-char (cadr hunk-bounds))
648 ;; bzr puts a newline after the last hunk.
649 (while (looking-at "^\n")
650 (forward-char 1))
651 (= (point) (cadr file-bounds))))
652 file-bounds
653 hunk-bounds))
654 (inhibit-read-only t))
655 (apply 'kill-region bounds)
656 (goto-char (car bounds))))
658 ;; "index ", "old mode", "new mode", "new file mode" and
659 ;; "deleted file mode" are output by git-diff.
660 (defconst diff-file-junk-re
661 "diff \\|index \\|\\(?:deleted file\\|new\\(?: file\\)?\\|old\\) mode\\|=== modified file")
663 (defun diff-beginning-of-file-and-junk ()
664 "Go to the beginning of file-related diff-info.
665 This is like `diff-beginning-of-file' except it tries to skip back over leading
666 data such as \"Index: ...\" and such."
667 (let* ((orig (point))
668 ;; Skip forward over what might be "leading junk" so as to get
669 ;; closer to the actual diff.
670 (_ (progn (beginning-of-line)
671 (while (looking-at diff-file-junk-re)
672 (forward-line 1))))
673 (start (point))
674 (prevfile (condition-case err
675 (save-excursion (diff-beginning-of-file) (point))
676 (error err)))
677 (err (if (consp prevfile) prevfile))
678 (nextfile (ignore-errors
679 (save-excursion
680 (goto-char start) (diff-file-next) (point))))
681 ;; prevhunk is one of the limits.
682 (prevhunk (save-excursion
683 (ignore-errors
684 (if (numberp prevfile) (goto-char prevfile))
685 (diff-hunk-prev) (point))))
686 (previndex (save-excursion
687 (forward-line 1) ;In case we're looking at "Index:".
688 (re-search-backward "^Index: " prevhunk t))))
689 ;; If we're in the junk, we should use nextfile instead of prevfile.
690 (if (and (numberp nextfile)
691 (or (not (numberp prevfile))
692 (and previndex (> previndex prevfile))))
693 (setq prevfile nextfile))
694 (if (and previndex (numberp prevfile) (< previndex prevfile))
695 (setq prevfile previndex))
696 (if (and (numberp prevfile) (<= prevfile start))
697 (progn
698 (goto-char prevfile)
699 ;; Now skip backward over the leading junk we may have before the
700 ;; diff itself.
701 (while (save-excursion
702 (and (zerop (forward-line -1))
703 (looking-at diff-file-junk-re)))
704 (forward-line -1)))
705 ;; File starts *after* the starting point: we really weren't in
706 ;; a file diff but elsewhere.
707 (goto-char orig)
708 (signal (car err) (cdr err)))))
710 (defun diff-file-kill ()
711 "Kill current file's hunks."
712 (interactive)
713 (let ((inhibit-read-only t))
714 (apply 'kill-region (diff-bounds-of-file))))
716 (defun diff-kill-junk ()
717 "Kill spurious empty diffs."
718 (interactive)
719 (save-excursion
720 (let ((inhibit-read-only t))
721 (goto-char (point-min))
722 (while (re-search-forward (concat "^\\(Index: .*\n\\)"
723 "\\([^-+!* <>].*\n\\)*?"
724 "\\(\\(Index:\\) \\|"
725 diff-file-header-re "\\)")
726 nil t)
727 (delete-region (if (match-end 4) (match-beginning 0) (match-end 1))
728 (match-beginning 3))
729 (beginning-of-line)))))
731 (defun diff-count-matches (re start end)
732 (save-excursion
733 (let ((n 0))
734 (goto-char start)
735 (while (re-search-forward re end t) (cl-incf n))
736 n)))
738 (defun diff-splittable-p ()
739 (save-excursion
740 (beginning-of-line)
741 (and (looking-at "^[-+ ]")
742 (progn (forward-line -1) (looking-at "^[-+ ]"))
743 (diff-unified-hunk-p))))
745 (defun diff-split-hunk ()
746 "Split the current (unified diff) hunk at point into two hunks."
747 (interactive)
748 (beginning-of-line)
749 (let ((pos (point))
750 (start (diff-beginning-of-hunk)))
751 (unless (looking-at diff-hunk-header-re-unified)
752 (error "diff-split-hunk only works on unified context diffs"))
753 (forward-line 1)
754 (let* ((start1 (string-to-number (match-string 1)))
755 (start2 (string-to-number (match-string 3)))
756 (newstart1 (+ start1 (diff-count-matches "^[- \t]" (point) pos)))
757 (newstart2 (+ start2 (diff-count-matches "^[+ \t]" (point) pos)))
758 (inhibit-read-only t))
759 (goto-char pos)
760 ;; Hopefully the after-change-function will not screw us over.
761 (insert "@@ -" (number-to-string newstart1) ",1 +"
762 (number-to-string newstart2) ",1 @@\n")
763 ;; Fix the original hunk-header.
764 (diff-fixup-modifs start pos))))
767 ;;;;
768 ;;;; jump to other buffers
769 ;;;;
771 (defvar diff-remembered-files-alist nil)
772 (defvar diff-remembered-defdir nil)
774 (defun diff-filename-drop-dir (file)
775 (when (string-match "/" file) (substring file (match-end 0))))
777 (defun diff-merge-strings (ancestor from to)
778 "Merge the diff between ANCESTOR and FROM into TO.
779 Returns the merged string if successful or nil otherwise.
780 The strings are assumed not to contain any \"\\n\" (i.e. end of line).
781 If ANCESTOR = FROM, returns TO.
782 If ANCESTOR = TO, returns FROM.
783 The heuristic is simplistic and only really works for cases
784 like \(diff-merge-strings \"b/foo\" \"b/bar\" \"/a/c/foo\")."
785 ;; Ideally, we want:
786 ;; AMB ANB CMD -> CND
787 ;; but that's ambiguous if `foo' or `bar' is empty:
788 ;; a/foo a/foo1 b/foo.c -> b/foo1.c but not 1b/foo.c or b/foo.c1
789 (let ((str (concat ancestor "\n" from "\n" to)))
790 (when (and (string-match (concat
791 "\\`\\(.*?\\)\\(.*\\)\\(.*\\)\n"
792 "\\1\\(.*\\)\\3\n"
793 "\\(.*\\(\\2\\).*\\)\\'") str)
794 (equal to (match-string 5 str)))
795 (concat (substring str (match-beginning 5) (match-beginning 6))
796 (match-string 4 str)
797 (substring str (match-end 6) (match-end 5))))))
799 (defun diff-tell-file-name (old name)
800 "Tell Emacs where the find the source file of the current hunk.
801 If the OLD prefix arg is passed, tell the file NAME of the old file."
802 (interactive
803 (let* ((old current-prefix-arg)
804 (fs (diff-hunk-file-names current-prefix-arg)))
805 (unless fs (error "No file name to look for"))
806 (list old (read-file-name (format "File for %s: " (car fs))
807 nil (diff-find-file-name old 'noprompt) t))))
808 (let ((fs (diff-hunk-file-names old)))
809 (unless fs (error "No file name to look for"))
810 (push (cons fs name) diff-remembered-files-alist)))
812 (defun diff-hunk-file-names (&optional old)
813 "Give the list of file names textually mentioned for the current hunk."
814 (save-excursion
815 (unless (looking-at diff-file-header-re)
816 (or (ignore-errors (diff-beginning-of-file))
817 (re-search-forward diff-file-header-re nil t)))
818 (let ((limit (save-excursion
819 (condition-case ()
820 (progn (diff-hunk-prev) (point))
821 (error (point-min)))))
822 (header-files
823 ;; handle filenames with spaces;
824 ;; cf. diff-font-lock-keywords / diff-file-header-face
825 (if (looking-at "[-*][-*][-*] \\([^\t]+\\)\t.*\n[-+][-+][-+] \\([^\t]+\\)")
826 (list (if old (match-string 1) (match-string 2))
827 (if old (match-string 2) (match-string 1)))
828 (forward-line 1) nil)))
829 (delq nil
830 (append
831 (when (and (not old)
832 (save-excursion
833 (re-search-backward "^Index: \\(.+\\)" limit t)))
834 (list (match-string 1)))
835 header-files
836 ;; this assumes that there are no spaces in filenames
837 (when (re-search-backward
838 "^diff \\(-\\S-+ +\\)*\\(\\S-+\\)\\( +\\(\\S-+\\)\\)?"
839 nil t)
840 (list (if old (match-string 2) (match-string 4))
841 (if old (match-string 4) (match-string 2)))))))))
843 (defun diff-find-file-name (&optional old noprompt prefix)
844 "Return the file corresponding to the current patch.
845 Non-nil OLD means that we want the old file.
846 Non-nil NOPROMPT means to prefer returning nil than to prompt the user.
847 PREFIX is only used internally: don't use it."
848 (unless (equal diff-remembered-defdir default-directory)
849 ;; Flush diff-remembered-files-alist if the default-directory is changed.
850 (set (make-local-variable 'diff-remembered-defdir) default-directory)
851 (set (make-local-variable 'diff-remembered-files-alist) nil))
852 (save-excursion
853 (unless (looking-at diff-file-header-re)
854 (or (ignore-errors (diff-beginning-of-file))
855 (re-search-forward diff-file-header-re nil t)))
856 (let ((fs (diff-hunk-file-names old)))
857 (if prefix (setq fs (mapcar (lambda (f) (concat prefix f)) fs)))
859 ;; use any previously used preference
860 (cdr (assoc fs diff-remembered-files-alist))
861 ;; try to be clever and use previous choices as an inspiration
862 (cl-dolist (rf diff-remembered-files-alist)
863 (let ((newfile (diff-merge-strings (caar rf) (car fs) (cdr rf))))
864 (if (and newfile (file-exists-p newfile)) (cl-return newfile))))
865 ;; look for each file in turn. If none found, try again but
866 ;; ignoring the first level of directory, ...
867 (cl-do* ((files fs (delq nil (mapcar 'diff-filename-drop-dir files)))
868 (file nil nil))
869 ((or (null files)
870 (setq file (cl-do* ((files files (cdr files))
871 (file (car files) (car files)))
872 ;; Use file-regular-p to avoid
873 ;; /dev/null, directories, etc.
874 ((or (null file) (file-regular-p file))
875 file))))
876 file))
877 ;; <foo>.rej patches implicitly apply to <foo>
878 (and (string-match "\\.rej\\'" (or buffer-file-name ""))
879 (let ((file (substring buffer-file-name 0 (match-beginning 0))))
880 (when (file-exists-p file) file)))
881 ;; If we haven't found the file, maybe it's because we haven't paid
882 ;; attention to the PCL-CVS hint.
883 (and (not prefix)
884 (boundp 'cvs-pcl-cvs-dirchange-re)
885 (save-excursion
886 (re-search-backward cvs-pcl-cvs-dirchange-re nil t))
887 (diff-find-file-name old noprompt (match-string 1)))
888 ;; if all else fails, ask the user
889 (unless noprompt
890 (let ((file (expand-file-name (or (car fs) ""))))
891 (setq file
892 (read-file-name (format "Use file %s: " file)
893 (file-name-directory file) file t
894 (file-name-nondirectory file)))
895 (set (make-local-variable 'diff-remembered-files-alist)
896 (cons (cons fs file) diff-remembered-files-alist))
897 file))))))
900 (defun diff-ediff-patch ()
901 "Call `ediff-patch-file' on the current buffer."
902 (interactive)
903 (condition-case nil
904 (ediff-patch-file nil (current-buffer))
905 (wrong-number-of-arguments (ediff-patch-file))))
907 ;;;;
908 ;;;; Conversion functions
909 ;;;;
911 ;;(defvar diff-inhibit-after-change nil
912 ;; "Non-nil means inhibit `diff-mode's after-change functions.")
914 (defun diff-unified->context (start end)
915 "Convert unified diffs to context diffs.
916 START and END are either taken from the region (if a prefix arg is given) or
917 else cover the whole buffer."
918 (interactive (if (or current-prefix-arg (use-region-p))
919 (list (region-beginning) (region-end))
920 (list (point-min) (point-max))))
921 (unless (markerp end) (setq end (copy-marker end t)))
922 (let (;;(diff-inhibit-after-change t)
923 (inhibit-read-only t))
924 (save-excursion
925 (goto-char start)
926 (while (and (re-search-forward
927 (concat "^\\(\\(---\\) .+\n\\(\\+\\+\\+\\) .+\\|"
928 diff-hunk-header-re-unified ".*\\)$")
929 nil t)
930 (< (point) end))
931 (combine-after-change-calls
932 (if (match-beginning 2)
933 ;; we matched a file header
934 (progn
935 ;; use reverse order to make sure the indices are kept valid
936 (replace-match "---" t t nil 3)
937 (replace-match "***" t t nil 2))
938 ;; we matched a hunk header
939 (let ((line1 (match-string 4))
940 (lines1 (or (match-string 5) "1"))
941 (line2 (match-string 6))
942 (lines2 (or (match-string 7) "1"))
943 ;; Variables to use the special undo function.
944 (old-undo buffer-undo-list)
945 (old-end (marker-position end))
946 (start (match-beginning 0))
947 (reversible t))
948 (replace-match
949 (concat "***************\n*** " line1 ","
950 (number-to-string (+ (string-to-number line1)
951 (string-to-number lines1)
952 -1))
953 " ****"))
954 (save-restriction
955 (narrow-to-region (line-beginning-position 2)
956 ;; Call diff-end-of-hunk from just before
957 ;; the hunk header so it can use the hunk
958 ;; header info.
959 (progn (diff-end-of-hunk 'unified) (point)))
960 (let ((hunk (buffer-string)))
961 (goto-char (point-min))
962 (if (not (save-excursion (re-search-forward "^-" nil t)))
963 (delete-region (point) (point-max))
964 (goto-char (point-max))
965 (let ((modif nil) last-pt)
966 (while (progn (setq last-pt (point))
967 (= (forward-line -1) 0))
968 (pcase (char-after)
969 (?\s (insert " ") (setq modif nil) (backward-char 1))
970 (?+ (delete-region (point) last-pt) (setq modif t))
971 (?- (if (not modif)
972 (progn (forward-char 1)
973 (insert " "))
974 (delete-char 1)
975 (insert "! "))
976 (backward-char 2))
977 (?\\ (when (save-excursion (forward-line -1)
978 (= (char-after) ?+))
979 (delete-region (point) last-pt)
980 (setq modif t)))
981 ;; diff-valid-unified-empty-line.
982 (?\n (insert " ") (setq modif nil)
983 (backward-char 2))
984 (_ (setq modif nil))))))
985 (goto-char (point-max))
986 (save-excursion
987 (insert "--- " line2 ","
988 (number-to-string (+ (string-to-number line2)
989 (string-to-number lines2)
990 -1))
991 " ----\n" hunk))
992 ;;(goto-char (point-min))
993 (forward-line 1)
994 (if (not (save-excursion (re-search-forward "^+" nil t)))
995 (delete-region (point) (point-max))
996 (let ((modif nil) (delete nil))
997 (if (save-excursion (re-search-forward "^\\+.*\n-"
998 nil t))
999 ;; Normally, lines in a substitution come with
1000 ;; first the removals and then the additions, and
1001 ;; the context->unified function follows this
1002 ;; convention, of course. Yet, other alternatives
1003 ;; are valid as well, but they preclude the use of
1004 ;; context->unified as an undo command.
1005 (setq reversible nil))
1006 (while (not (eobp))
1007 (pcase (char-after)
1008 (?\s (insert " ") (setq modif nil) (backward-char 1))
1009 (?- (setq delete t) (setq modif t))
1010 (?+ (if (not modif)
1011 (progn (forward-char 1)
1012 (insert " "))
1013 (delete-char 1)
1014 (insert "! "))
1015 (backward-char 2))
1016 (?\\ (when (save-excursion (forward-line 1)
1017 (not (eobp)))
1018 (setq delete t) (setq modif t)))
1019 ;; diff-valid-unified-empty-line.
1020 (?\n (insert " ") (setq modif nil) (backward-char 2)
1021 (setq reversible nil))
1022 (_ (setq modif nil)))
1023 (let ((last-pt (point)))
1024 (forward-line 1)
1025 (when delete
1026 (delete-region last-pt (point))
1027 (setq delete nil)))))))
1028 (unless (or (not reversible) (eq buffer-undo-list t))
1029 ;; Drop the many undo entries and replace them with
1030 ;; a single entry that uses diff-context->unified to do
1031 ;; the work.
1032 (setq buffer-undo-list
1033 (cons (list 'apply (- old-end end) start (point-max)
1034 'diff-context->unified start (point-max))
1035 old-undo)))))))))))
1037 (defun diff-context->unified (start end &optional to-context)
1038 "Convert context diffs to unified diffs.
1039 START and END are either taken from the region
1040 \(when it is highlighted) or else cover the whole buffer.
1041 With a prefix argument, convert unified format to context format."
1042 (interactive (if (use-region-p)
1043 (list (region-beginning) (region-end) current-prefix-arg)
1044 (list (point-min) (point-max) current-prefix-arg)))
1045 (if to-context
1046 (diff-unified->context start end)
1047 (unless (markerp end) (setq end (copy-marker end t)))
1048 (let ( ;;(diff-inhibit-after-change t)
1049 (inhibit-read-only t))
1050 (save-excursion
1051 (goto-char start)
1052 (while (and (re-search-forward "^\\(\\(\\*\\*\\*\\) .+\n\\(---\\) .+\\|\\*\\{15\\}.*\n\\*\\*\\* \\([0-9]+\\),\\(-?[0-9]+\\) \\*\\*\\*\\*\\)\\(?: \\(.*\\)\\|$\\)" nil t)
1053 (< (point) end))
1054 (combine-after-change-calls
1055 (if (match-beginning 2)
1056 ;; we matched a file header
1057 (progn
1058 ;; use reverse order to make sure the indices are kept valid
1059 (replace-match "+++" t t nil 3)
1060 (replace-match "---" t t nil 2))
1061 ;; we matched a hunk header
1062 (let ((line1s (match-string 4))
1063 (line1e (match-string 5))
1064 (pt1 (match-beginning 0))
1065 ;; Variables to use the special undo function.
1066 (old-undo buffer-undo-list)
1067 (old-end (marker-position end))
1068 ;; We currently throw away the comment that can follow
1069 ;; the hunk header. FIXME: Preserve it instead!
1070 (reversible (not (match-end 6))))
1071 (replace-match "")
1072 (unless (re-search-forward
1073 diff-context-mid-hunk-header-re nil t)
1074 (error "Can't find matching `--- n1,n2 ----' line"))
1075 (let ((line2s (match-string 1))
1076 (line2e (match-string 2))
1077 (pt2 (progn
1078 (delete-region (progn (beginning-of-line) (point))
1079 (progn (forward-line 1) (point)))
1080 (point-marker))))
1081 (goto-char pt1)
1082 (forward-line 1)
1083 (while (< (point) pt2)
1084 (pcase (char-after)
1085 (?! (delete-char 2) (insert "-") (forward-line 1))
1086 (?- (forward-char 1) (delete-char 1) (forward-line 1))
1087 (?\s ;merge with the other half of the chunk
1088 (let* ((endline2
1089 (save-excursion
1090 (goto-char pt2) (forward-line 1) (point))))
1091 (pcase (char-after pt2)
1092 ((or ?! ?+)
1093 (insert "+"
1094 (prog1
1095 (buffer-substring (+ pt2 2) endline2)
1096 (delete-region pt2 endline2))))
1097 (?\s
1098 (unless (= (- endline2 pt2)
1099 (- (line-beginning-position 2) (point)))
1100 ;; If the two lines we're merging don't have the
1101 ;; same length (can happen with "diff -b"), then
1102 ;; diff-unified->context will not properly undo
1103 ;; this operation.
1104 (setq reversible nil))
1105 (delete-region pt2 endline2)
1106 (delete-char 1)
1107 (forward-line 1))
1108 (?\\ (forward-line 1))
1109 (_ (setq reversible nil)
1110 (delete-char 1) (forward-line 1)))))
1111 (_ (setq reversible nil) (forward-line 1))))
1112 (while (looking-at "[+! ] ")
1113 (if (/= (char-after) ?!) (forward-char 1)
1114 (delete-char 1) (insert "+"))
1115 (delete-char 1) (forward-line 1))
1116 (save-excursion
1117 (goto-char pt1)
1118 (insert "@@ -" line1s ","
1119 (number-to-string (- (string-to-number line1e)
1120 (string-to-number line1s)
1121 -1))
1122 " +" line2s ","
1123 (number-to-string (- (string-to-number line2e)
1124 (string-to-number line2s)
1125 -1)) " @@"))
1126 (set-marker pt2 nil)
1127 ;; The whole procedure succeeded, let's replace the myriad
1128 ;; of undo elements with just a single special one.
1129 (unless (or (not reversible) (eq buffer-undo-list t))
1130 (setq buffer-undo-list
1131 (cons (list 'apply (- old-end end) pt1 (point)
1132 'diff-unified->context pt1 (point))
1133 old-undo)))
1134 )))))))))
1136 (defun diff-reverse-direction (start end)
1137 "Reverse the direction of the diffs.
1138 START and END are either taken from the region (if a prefix arg is given) or
1139 else cover the whole buffer."
1140 (interactive (if (or current-prefix-arg (use-region-p))
1141 (list (region-beginning) (region-end))
1142 (list (point-min) (point-max))))
1143 (unless (markerp end) (setq end (copy-marker end t)))
1144 (let (;;(diff-inhibit-after-change t)
1145 (inhibit-read-only t))
1146 (save-excursion
1147 (goto-char start)
1148 (while (and (re-search-forward "^\\(\\([-*][-*][-*] \\)\\(.+\\)\n\\([-+][-+][-+] \\)\\(.+\\)\\|\\*\\{15\\}.*\n\\*\\*\\* \\(.+\\) \\*\\*\\*\\*\\|@@ -\\([0-9,]+\\) \\+\\([0-9,]+\\) @@.*\\)$" nil t)
1149 (< (point) end))
1150 (combine-after-change-calls
1151 (cond
1152 ;; a file header
1153 ((match-beginning 2) (replace-match "\\2\\5\n\\4\\3" nil))
1154 ;; a context-diff hunk header
1155 ((match-beginning 6)
1156 (let ((pt-lines1 (match-beginning 6))
1157 (lines1 (match-string 6)))
1158 (replace-match "" nil nil nil 6)
1159 (forward-line 1)
1160 (let ((half1s (point)))
1161 (while (looking-at "[-! \\][ \t]\\|#")
1162 (when (= (char-after) ?-) (delete-char 1) (insert "+"))
1163 (forward-line 1))
1164 (let ((half1 (delete-and-extract-region half1s (point))))
1165 (unless (looking-at diff-context-mid-hunk-header-re)
1166 (insert half1)
1167 (error "Can't find matching `--- n1,n2 ----' line"))
1168 (let* ((str1end (or (match-end 2) (match-end 1)))
1169 (str1 (buffer-substring (match-beginning 1) str1end)))
1170 (goto-char str1end)
1171 (insert lines1)
1172 (delete-region (match-beginning 1) str1end)
1173 (forward-line 1)
1174 (let ((half2s (point)))
1175 (while (looking-at "[!+ \\][ \t]\\|#")
1176 (when (= (char-after) ?+) (delete-char 1) (insert "-"))
1177 (forward-line 1))
1178 (let ((half2 (delete-and-extract-region half2s (point))))
1179 (insert (or half1 ""))
1180 (goto-char half1s)
1181 (insert (or half2 ""))))
1182 (goto-char pt-lines1)
1183 (insert str1))))))
1184 ;; a unified-diff hunk header
1185 ((match-beginning 7)
1186 (replace-match "@@ -\\8 +\\7 @@" nil)
1187 (forward-line 1)
1188 (let ((c (char-after)) first last)
1189 (while (pcase (setq c (char-after))
1190 (?- (setq first (or first (point)))
1191 (delete-char 1) (insert "+") t)
1192 (?+ (setq last (or last (point)))
1193 (delete-char 1) (insert "-") t)
1194 ((or ?\\ ?#) t)
1195 (_ (when (and first last (< first last))
1196 (insert (delete-and-extract-region first last)))
1197 (setq first nil last nil)
1198 (memq c (if diff-valid-unified-empty-line
1199 '(?\s ?\n) '(?\s)))))
1200 (forward-line 1))))))))))
1202 (defun diff-fixup-modifs (start end)
1203 "Fixup the hunk headers (in case the buffer was modified).
1204 START and END are either taken from the region (if a prefix arg is given) or
1205 else cover the whole buffer."
1206 (interactive (if (or current-prefix-arg (use-region-p))
1207 (list (region-beginning) (region-end))
1208 (list (point-min) (point-max))))
1209 (let ((inhibit-read-only t))
1210 (save-excursion
1211 (goto-char end) (diff-end-of-hunk nil 'donttrustheader)
1212 (let ((plus 0) (minus 0) (space 0) (bang 0))
1213 (while (and (= (forward-line -1) 0) (<= start (point)))
1214 (if (not (looking-at
1215 (concat diff-hunk-header-re-unified
1216 "\\|[-*][-*][-*] [0-9,]+ [-*][-*][-*][-*]$"
1217 "\\|--- .+\n\\+\\+\\+ ")))
1218 (pcase (char-after)
1219 (?\s (cl-incf space))
1220 (?+ (cl-incf plus))
1221 (?- (cl-incf minus))
1222 (?! (cl-incf bang))
1223 ((or ?\\ ?#) nil)
1224 (_ (setq space 0 plus 0 minus 0 bang 0)))
1225 (cond
1226 ((looking-at diff-hunk-header-re-unified)
1227 (let* ((old1 (match-string 2))
1228 (old2 (match-string 4))
1229 (new1 (number-to-string (+ space minus)))
1230 (new2 (number-to-string (+ space plus))))
1231 (if old2
1232 (unless (string= new2 old2) (replace-match new2 t t nil 4))
1233 (goto-char (match-end 3))
1234 (insert "," new2))
1235 (if old1
1236 (unless (string= new1 old1) (replace-match new1 t t nil 2))
1237 (goto-char (match-end 1))
1238 (insert "," new1))))
1239 ((looking-at diff-context-mid-hunk-header-re)
1240 (when (> (+ space bang plus) 0)
1241 (let* ((old1 (match-string 1))
1242 (old2 (match-string 2))
1243 (new (number-to-string
1244 (+ space bang plus -1 (string-to-number old1)))))
1245 (unless (string= new old2) (replace-match new t t nil 2)))))
1246 ((looking-at "\\*\\*\\* \\([0-9]+\\),\\(-?[0-9]*\\) \\*\\*\\*\\*$")
1247 (when (> (+ space bang minus) 0)
1248 (let* ((old (match-string 1))
1249 (new (format
1250 (concat "%0" (number-to-string (length old)) "d")
1251 (+ space bang minus -1 (string-to-number old)))))
1252 (unless (string= new old) (replace-match new t t nil 2))))))
1253 (setq space 0 plus 0 minus 0 bang 0)))))))
1255 ;;;;
1256 ;;;; Hooks
1257 ;;;;
1259 (defun diff-write-contents-hooks ()
1260 "Fixup hunk headers if necessary."
1261 (if (buffer-modified-p) (diff-fixup-modifs (point-min) (point-max)))
1262 nil)
1264 ;; It turns out that making changes in the buffer from within an
1265 ;; *-change-function is asking for trouble, whereas making them
1266 ;; from a post-command-hook doesn't pose much problems
1267 (defvar diff-unhandled-changes nil)
1268 (defun diff-after-change-function (beg end _len)
1269 "Remember to fixup the hunk header.
1270 See `after-change-functions' for the meaning of BEG, END and LEN."
1271 ;; Ignoring changes when inhibit-read-only is set is strictly speaking
1272 ;; incorrect, but it turns out that inhibit-read-only is normally not set
1273 ;; inside editing commands, while it tends to be set when the buffer gets
1274 ;; updated by an async process or by a conversion function, both of which
1275 ;; would rather not be uselessly slowed down by this hook.
1276 (when (and (not undo-in-progress) (not inhibit-read-only))
1277 (if diff-unhandled-changes
1278 (setq diff-unhandled-changes
1279 (cons (min beg (car diff-unhandled-changes))
1280 (max end (cdr diff-unhandled-changes))))
1281 (setq diff-unhandled-changes (cons beg end)))))
1283 (defun diff-post-command-hook ()
1284 "Fixup hunk headers if necessary."
1285 (when (consp diff-unhandled-changes)
1286 (ignore-errors
1287 (save-excursion
1288 (goto-char (car diff-unhandled-changes))
1289 ;; Maybe we've cut the end of the hunk before point.
1290 (if (and (bolp) (not (bobp))) (backward-char 1))
1291 ;; We used to fixup modifs on all the changes, but it turns out that
1292 ;; it's safer not to do it on big changes, e.g. when yanking a big
1293 ;; diff, or when the user edits the header, since we might then
1294 ;; screw up perfectly correct values. --Stef
1295 (diff-beginning-of-hunk)
1296 (let* ((style (if (looking-at "\\*\\*\\*") 'context))
1297 (start (line-beginning-position (if (eq style 'context) 3 2)))
1298 (mid (if (eq style 'context)
1299 (save-excursion
1300 (re-search-forward diff-context-mid-hunk-header-re
1301 nil t)))))
1302 (when (and ;; Don't try to fixup changes in the hunk header.
1303 (>= (car diff-unhandled-changes) start)
1304 ;; Don't try to fixup changes in the mid-hunk header either.
1305 (or (not mid)
1306 (< (cdr diff-unhandled-changes) (match-beginning 0))
1307 (> (car diff-unhandled-changes) (match-end 0)))
1308 (save-excursion
1309 (diff-end-of-hunk nil 'donttrustheader)
1310 ;; Don't try to fixup changes past the end of the hunk.
1311 (>= (point) (cdr diff-unhandled-changes))))
1312 (diff-fixup-modifs (point) (cdr diff-unhandled-changes)))))
1313 (setq diff-unhandled-changes nil))))
1315 (defun diff-next-error (arg reset)
1316 ;; Select a window that displays the current buffer so that point
1317 ;; movements are reflected in that window. Otherwise, the user might
1318 ;; never see the hunk corresponding to the source she's jumping to.
1319 (pop-to-buffer (current-buffer))
1320 (if reset (goto-char (point-min)))
1321 (diff-hunk-next arg)
1322 (diff-goto-source))
1324 (defvar whitespace-style)
1325 (defvar whitespace-trailing-regexp)
1327 ;;;###autoload
1328 (define-derived-mode diff-mode fundamental-mode "Diff"
1329 "Major mode for viewing/editing context diffs.
1330 Supports unified and context diffs as well as (to a lesser extent)
1331 normal diffs.
1333 When the buffer is read-only, the ESC prefix is not necessary.
1334 If you edit the buffer manually, diff-mode will try to update the hunk
1335 headers for you on-the-fly.
1337 You can also switch between context diff and unified diff with \\[diff-context->unified],
1338 or vice versa with \\[diff-unified->context] and you can also reverse the direction of
1339 a diff with \\[diff-reverse-direction].
1341 \\{diff-mode-map}"
1343 (set (make-local-variable 'font-lock-defaults) diff-font-lock-defaults)
1344 (add-hook 'font-lock-mode-hook
1345 (lambda () (remove-overlays nil nil 'diff-mode 'fine))
1346 nil 'local)
1347 (set (make-local-variable 'outline-regexp) diff-outline-regexp)
1348 (set (make-local-variable 'imenu-generic-expression)
1349 diff-imenu-generic-expression)
1350 ;; These are not perfect. They would be better done separately for
1351 ;; context diffs and unidiffs.
1352 ;; (set (make-local-variable 'paragraph-start)
1353 ;; (concat "@@ " ; unidiff hunk
1354 ;; "\\|\\*\\*\\* " ; context diff hunk or file start
1355 ;; "\\|--- [^\t]+\t")) ; context or unidiff file
1356 ;; ; start (first or second line)
1357 ;; (set (make-local-variable 'paragraph-separate) paragraph-start)
1358 ;; (set (make-local-variable 'page-delimiter) "--- [^\t]+\t")
1359 ;; compile support
1360 (set (make-local-variable 'next-error-function) 'diff-next-error)
1362 (set (make-local-variable 'beginning-of-defun-function)
1363 'diff-beginning-of-file-and-junk)
1364 (set (make-local-variable 'end-of-defun-function)
1365 'diff-end-of-file)
1367 (diff-setup-whitespace)
1369 (if diff-default-read-only
1370 (setq buffer-read-only t))
1371 ;; setup change hooks
1372 (if (not diff-update-on-the-fly)
1373 (add-hook 'write-contents-functions 'diff-write-contents-hooks nil t)
1374 (make-local-variable 'diff-unhandled-changes)
1375 (add-hook 'after-change-functions 'diff-after-change-function nil t)
1376 (add-hook 'post-command-hook 'diff-post-command-hook nil t))
1377 ;; Neat trick from Dave Love to add more bindings in read-only mode:
1378 (let ((ro-bind (cons 'buffer-read-only diff-mode-shared-map)))
1379 (add-to-list 'minor-mode-overriding-map-alist ro-bind)
1380 ;; Turn off this little trick in case the buffer is put in view-mode.
1381 (add-hook 'view-mode-hook
1382 (lambda ()
1383 (setq minor-mode-overriding-map-alist
1384 (delq ro-bind minor-mode-overriding-map-alist)))
1385 nil t))
1386 ;; add-log support
1387 (set (make-local-variable 'add-log-current-defun-function)
1388 'diff-current-defun)
1389 (set (make-local-variable 'add-log-buffer-file-name-function)
1390 (lambda () (diff-find-file-name nil 'noprompt)))
1391 (unless (buffer-file-name)
1392 (hack-dir-local-variables-non-file-buffer)))
1394 ;;;###autoload
1395 (define-minor-mode diff-minor-mode
1396 "Toggle Diff minor mode.
1397 With a prefix argument ARG, enable Diff minor mode if ARG is
1398 positive, and disable it otherwise. If called from Lisp, enable
1399 the mode if ARG is omitted or nil.
1401 \\{diff-minor-mode-map}"
1402 :group 'diff-mode :lighter " Diff"
1403 ;; FIXME: setup font-lock
1404 ;; setup change hooks
1405 (if (not diff-update-on-the-fly)
1406 (add-hook 'write-contents-functions 'diff-write-contents-hooks nil t)
1407 (make-local-variable 'diff-unhandled-changes)
1408 (add-hook 'after-change-functions 'diff-after-change-function nil t)
1409 (add-hook 'post-command-hook 'diff-post-command-hook nil t)))
1411 ;;; Handy hook functions ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
1413 (defun diff-setup-whitespace ()
1414 "Set up Whitespace mode variables for the current Diff mode buffer.
1415 This sets `whitespace-style' and `whitespace-trailing-regexp' so
1416 that Whitespace mode shows trailing whitespace problems on the
1417 modified lines of the diff."
1418 (set (make-local-variable 'whitespace-style) '(face trailing))
1419 (let ((style (save-excursion
1420 (goto-char (point-min))
1421 ;; FIXME: For buffers filled from async processes, this search
1422 ;; will simply fail because the buffer is still empty :-(
1423 (when (re-search-forward diff-hunk-header-re nil t)
1424 (goto-char (match-beginning 0))
1425 (diff-hunk-style)))))
1426 (set (make-local-variable 'whitespace-trailing-regexp)
1427 (if (eq style 'context)
1428 "^[-\+!] .*?\\([\t ]+\\)$"
1429 "^[-\+!<>].*?\\([\t ]+\\)$"))))
1431 (defun diff-delete-if-empty ()
1432 ;; An empty diff file means there's no more diffs to integrate, so we
1433 ;; can just remove the file altogether. Very handy for .rej files if we
1434 ;; remove hunks as we apply them.
1435 (when (and buffer-file-name
1436 (eq 0 (nth 7 (file-attributes buffer-file-name))))
1437 (delete-file buffer-file-name)))
1439 (defun diff-delete-empty-files ()
1440 "Arrange for empty diff files to be removed."
1441 (add-hook 'after-save-hook 'diff-delete-if-empty nil t))
1443 (defun diff-make-unified ()
1444 "Turn context diffs into unified diffs if applicable."
1445 (if (save-excursion
1446 (goto-char (point-min))
1447 (and (looking-at diff-hunk-header-re) (eq (char-after) ?*)))
1448 (let ((mod (buffer-modified-p)))
1449 (unwind-protect
1450 (diff-context->unified (point-min) (point-max))
1451 (restore-buffer-modified-p mod)))))
1454 ;;; Misc operations that have proved useful at some point.
1457 (defun diff-next-complex-hunk ()
1458 "Jump to the next \"complex\" hunk.
1459 \"Complex\" is approximated by \"the hunk changes the number of lines\".
1460 Only works for unified diffs."
1461 (interactive)
1462 (while
1463 (and (re-search-forward diff-hunk-header-re-unified nil t)
1464 (equal (match-string 2) (match-string 4)))))
1466 (defun diff-sanity-check-context-hunk-half (lines)
1467 (let ((count lines))
1468 (while
1469 (cond
1470 ((and (memq (char-after) '(?\s ?! ?+ ?-))
1471 (memq (char-after (1+ (point))) '(?\s ?\t)))
1472 (cl-decf count) t)
1473 ((or (zerop count) (= count lines)) nil)
1474 ((memq (char-after) '(?! ?+ ?-))
1475 (if (not (and (eq (char-after (1+ (point))) ?\n)
1476 (y-or-n-p "Try to auto-fix whitespace loss damage? ")))
1477 (error "End of hunk ambiguously marked")
1478 (forward-char 1) (insert " ") (forward-line -1) t))
1479 ((< lines 0)
1480 (error "End of hunk ambiguously marked"))
1481 ((not (y-or-n-p "Try to auto-fix whitespace loss and word-wrap damage? "))
1482 (error "Abort!"))
1483 ((eolp) (insert " ") (forward-line -1) t)
1484 (t (insert " ") (delete-region (- (point) 2) (- (point) 1)) t))
1485 (forward-line))))
1487 (defun diff-sanity-check-hunk ()
1488 (let (;; Every modification is protected by a y-or-n-p, so it's probably
1489 ;; OK to override a read-only setting.
1490 (inhibit-read-only t))
1491 (save-excursion
1492 (cond
1493 ((not (looking-at diff-hunk-header-re))
1494 (error "Not recognizable hunk header"))
1496 ;; A context diff.
1497 ((eq (char-after) ?*)
1498 (if (not (looking-at "\\*\\{15\\}\\(?: .*\\)?\n\\*\\*\\* \\([0-9]+\\)\\(?:,\\([0-9]+\\)\\)? \\*\\*\\*\\*"))
1499 (error "Unrecognized context diff first hunk header format")
1500 (forward-line 2)
1501 (diff-sanity-check-context-hunk-half
1502 (if (match-end 2)
1503 (1+ (- (string-to-number (match-string 2))
1504 (string-to-number (match-string 1))))
1506 (if (not (looking-at diff-context-mid-hunk-header-re))
1507 (error "Unrecognized context diff second hunk header format")
1508 (forward-line)
1509 (diff-sanity-check-context-hunk-half
1510 (if (match-end 2)
1511 (1+ (- (string-to-number (match-string 2))
1512 (string-to-number (match-string 1))))
1513 1)))))
1515 ;; A unified diff.
1516 ((eq (char-after) ?@)
1517 (if (not (looking-at diff-hunk-header-re-unified))
1518 (error "Unrecognized unified diff hunk header format")
1519 (let ((before (string-to-number (or (match-string 2) "1")))
1520 (after (string-to-number (or (match-string 4) "1"))))
1521 (forward-line)
1522 (while
1523 (pcase (char-after)
1524 (?\s (cl-decf before) (cl-decf after) t)
1526 (if (and (looking-at diff-file-header-re)
1527 (zerop before) (zerop after))
1528 ;; No need to query: this is a case where two patches
1529 ;; are concatenated and only counting the lines will
1530 ;; give the right result. Let's just add an empty
1531 ;; line so that our code which doesn't count lines
1532 ;; will not get confused.
1533 (progn (save-excursion (insert "\n")) nil)
1534 (cl-decf before) t))
1535 (?+ (cl-decf after) t)
1537 (cond
1538 ((and diff-valid-unified-empty-line
1539 ;; Not just (eolp) so we don't infloop at eob.
1540 (eq (char-after) ?\n)
1541 (> before 0) (> after 0))
1542 (cl-decf before) (cl-decf after) t)
1543 ((and (zerop before) (zerop after)) nil)
1544 ((or (< before 0) (< after 0))
1545 (error (if (or (zerop before) (zerop after))
1546 "End of hunk ambiguously marked"
1547 "Hunk seriously messed up")))
1548 ((not (y-or-n-p (concat "Try to auto-fix " (if (eolp) "whitespace loss" "word-wrap damage") "? ")))
1549 (error "Abort!"))
1550 ((eolp) (insert " ") (forward-line -1) t)
1551 (t (insert " ")
1552 (delete-region (- (point) 2) (- (point) 1)) t))))
1553 (forward-line)))))
1555 ;; A plain diff.
1557 ;; TODO.
1558 )))))
1560 (defun diff-hunk-text (hunk destp char-offset)
1561 "Return the literal source text from HUNK as (TEXT . OFFSET).
1562 If DESTP is nil, TEXT is the source, otherwise the destination text.
1563 CHAR-OFFSET is a char-offset in HUNK, and OFFSET is the corresponding
1564 char-offset in TEXT."
1565 (with-temp-buffer
1566 (insert hunk)
1567 (goto-char (point-min))
1568 (let ((src-pos nil)
1569 (dst-pos nil)
1570 (divider-pos nil)
1571 (num-pfx-chars 2))
1572 ;; Set the following variables:
1573 ;; SRC-POS buffer pos of the source part of the hunk or nil if none
1574 ;; DST-POS buffer pos of the destination part of the hunk or nil
1575 ;; DIVIDER-POS buffer pos of any divider line separating the src & dst
1576 ;; NUM-PFX-CHARS number of line-prefix characters used by this format"
1577 (cond ((looking-at "^@@")
1578 ;; unified diff
1579 (setq num-pfx-chars 1)
1580 (forward-line 1)
1581 (setq src-pos (point) dst-pos (point)))
1582 ((looking-at "^\\*\\*")
1583 ;; context diff
1584 (forward-line 2)
1585 (setq src-pos (point))
1586 (re-search-forward diff-context-mid-hunk-header-re nil t)
1587 (forward-line 0)
1588 (setq divider-pos (point))
1589 (forward-line 1)
1590 (setq dst-pos (point)))
1591 ((looking-at "^[0-9]+a[0-9,]+$")
1592 ;; normal diff, insert
1593 (forward-line 1)
1594 (setq dst-pos (point)))
1595 ((looking-at "^[0-9,]+d[0-9]+$")
1596 ;; normal diff, delete
1597 (forward-line 1)
1598 (setq src-pos (point)))
1599 ((looking-at "^[0-9,]+c[0-9,]+$")
1600 ;; normal diff, change
1601 (forward-line 1)
1602 (setq src-pos (point))
1603 (re-search-forward "^---$" nil t)
1604 (forward-line 0)
1605 (setq divider-pos (point))
1606 (forward-line 1)
1607 (setq dst-pos (point)))
1609 (error "Unknown diff hunk type")))
1611 (if (if destp (null dst-pos) (null src-pos))
1612 ;; Implied empty text
1613 (if char-offset '("" . 0) "")
1615 ;; For context diffs, either side can be empty, (if there's only
1616 ;; added or only removed text). We should then use the other side.
1617 (cond ((equal src-pos divider-pos) (setq src-pos dst-pos))
1618 ((equal dst-pos (point-max)) (setq dst-pos src-pos)))
1620 (when char-offset (goto-char (+ (point-min) char-offset)))
1622 ;; Get rid of anything except the desired text.
1623 (save-excursion
1624 ;; Delete unused text region
1625 (let ((keep (if destp dst-pos src-pos)))
1626 (when (and divider-pos (> divider-pos keep))
1627 (delete-region divider-pos (point-max)))
1628 (delete-region (point-min) keep))
1629 ;; Remove line-prefix characters, and unneeded lines (unified diffs).
1630 (let ((kill-char (if destp ?- ?+)))
1631 (goto-char (point-min))
1632 (while (not (eobp))
1633 (if (eq (char-after) kill-char)
1634 (delete-region (point) (progn (forward-line 1) (point)))
1635 (delete-char num-pfx-chars)
1636 (forward-line 1)))))
1638 (let ((text (buffer-substring-no-properties (point-min) (point-max))))
1639 (if char-offset (cons text (- (point) (point-min))) text))))))
1642 (defun diff-find-text (text)
1643 "Return the buffer position (BEG . END) of the nearest occurrence of TEXT.
1644 If TEXT isn't found, nil is returned."
1645 (let* ((orig (point))
1646 (forw (and (search-forward text nil t)
1647 (cons (match-beginning 0) (match-end 0))))
1648 (back (and (goto-char (+ orig (length text)))
1649 (search-backward text nil t)
1650 (cons (match-beginning 0) (match-end 0)))))
1651 ;; Choose the closest match.
1652 (if (and forw back)
1653 (if (> (- (car forw) orig) (- orig (car back))) back forw)
1654 (or back forw))))
1656 (defun diff-find-approx-text (text)
1657 "Return the buffer position (BEG . END) of the nearest occurrence of TEXT.
1658 Whitespace differences are ignored."
1659 (let* ((orig (point))
1660 (re (concat "^[ \t\n\f]*"
1661 (mapconcat 'regexp-quote (split-string text) "[ \t\n\f]+")
1662 "[ \t\n\f]*\n"))
1663 (forw (and (re-search-forward re nil t)
1664 (cons (match-beginning 0) (match-end 0))))
1665 (back (and (goto-char (+ orig (length text)))
1666 (re-search-backward re nil t)
1667 (cons (match-beginning 0) (match-end 0)))))
1668 ;; Choose the closest match.
1669 (if (and forw back)
1670 (if (> (- (car forw) orig) (- orig (car back))) back forw)
1671 (or back forw))))
1673 (defsubst diff-xor (a b) (if a (if (not b) a) b))
1675 (defun diff-find-source-location (&optional other-file reverse noprompt)
1676 "Find out (BUF LINE-OFFSET POS SRC DST SWITCHED).
1677 BUF is the buffer corresponding to the source file.
1678 LINE-OFFSET is the offset between the expected and actual positions
1679 of the text of the hunk or nil if the text was not found.
1680 POS is a pair (BEG . END) indicating the position of the text in the buffer.
1681 SRC and DST are the two variants of text as returned by `diff-hunk-text'.
1682 SRC is the variant that was found in the buffer.
1683 SWITCHED is non-nil if the patch is already applied.
1684 NOPROMPT, if non-nil, means not to prompt the user."
1685 (save-excursion
1686 (let* ((other (diff-xor other-file diff-jump-to-old-file))
1687 (char-offset (- (point) (diff-beginning-of-hunk t)))
1688 ;; Check that the hunk is well-formed. Otherwise diff-mode and
1689 ;; the user may disagree on what constitutes the hunk
1690 ;; (e.g. because an empty line truncates the hunk mid-course),
1691 ;; leading to potentially nasty surprises for the user.
1693 ;; Suppress check when NOPROMPT is non-nil (Bug#3033).
1694 (_ (unless noprompt (diff-sanity-check-hunk)))
1695 (hunk (buffer-substring
1696 (point) (save-excursion (diff-end-of-hunk) (point))))
1697 (old (diff-hunk-text hunk reverse char-offset))
1698 (new (diff-hunk-text hunk (not reverse) char-offset))
1699 ;; Find the location specification.
1700 (line (if (not (looking-at "\\(?:\\*\\{15\\}.*\n\\)?[-@* ]*\\([0-9,]+\\)\\([ acd+]+\\([0-9,]+\\)\\)?"))
1701 (error "Can't find the hunk header")
1702 (if other (match-string 1)
1703 (if (match-end 3) (match-string 3)
1704 (unless (re-search-forward
1705 diff-context-mid-hunk-header-re nil t)
1706 (error "Can't find the hunk separator"))
1707 (match-string 1)))))
1708 (file (or (diff-find-file-name other noprompt)
1709 (error "Can't find the file")))
1710 (buf (find-file-noselect file)))
1711 ;; Update the user preference if he so wished.
1712 (when (> (prefix-numeric-value other-file) 8)
1713 (setq diff-jump-to-old-file other))
1714 (with-current-buffer buf
1715 (goto-char (point-min)) (forward-line (1- (string-to-number line)))
1716 (let* ((orig-pos (point))
1717 (switched nil)
1718 ;; FIXME: Check for case where both OLD and NEW are found.
1719 (pos (or (diff-find-text (car old))
1720 (progn (setq switched t) (diff-find-text (car new)))
1721 (progn (setq switched nil)
1722 (condition-case nil
1723 (diff-find-approx-text (car old))
1724 (invalid-regexp nil))) ;Regex too big.
1725 (progn (setq switched t)
1726 (condition-case nil
1727 (diff-find-approx-text (car new))
1728 (invalid-regexp nil))) ;Regex too big.
1729 (progn (setq switched nil) nil))))
1730 (nconc
1731 (list buf)
1732 (if pos
1733 (list (count-lines orig-pos (car pos)) pos)
1734 (list nil (cons orig-pos (+ orig-pos (length (car old))))))
1735 (if switched (list new old t) (list old new))))))))
1738 (defun diff-hunk-status-msg (line-offset reversed dry-run)
1739 (let ((msg (if dry-run
1740 (if reversed "already applied" "not yet applied")
1741 (if reversed "undone" "applied"))))
1742 (message (cond ((null line-offset) "Hunk text not found")
1743 ((= line-offset 0) "Hunk %s")
1744 ((= line-offset 1) "Hunk %s at offset %d line")
1745 (t "Hunk %s at offset %d lines"))
1746 msg line-offset)))
1748 (defvar diff-apply-hunk-to-backup-file nil)
1750 (defun diff-apply-hunk (&optional reverse)
1751 "Apply the current hunk to the source file and go to the next.
1752 By default, the new source file is patched, but if the variable
1753 `diff-jump-to-old-file' is non-nil, then the old source file is
1754 patched instead (some commands, such as `diff-goto-source' can change
1755 the value of this variable when given an appropriate prefix argument).
1757 With a prefix argument, REVERSE the hunk."
1758 (interactive "P")
1759 (pcase-let ((`(,buf ,line-offset ,pos ,old ,new ,switched)
1760 ;; Sometimes we'd like to have the following behavior: if
1761 ;; REVERSE go to the new file, otherwise go to the old.
1762 ;; But that means that by default we use the old file, which is
1763 ;; the opposite of the default for diff-goto-source, and is thus
1764 ;; confusing. Also when you don't know about it it's
1765 ;; pretty surprising.
1766 ;; TODO: make it possible to ask explicitly for this behavior.
1768 ;; This is duplicated in diff-test-hunk.
1769 (diff-find-source-location nil reverse)))
1770 (cond
1771 ((null line-offset)
1772 (error "Can't find the text to patch"))
1773 ((with-current-buffer buf
1774 (and buffer-file-name
1775 (backup-file-name-p buffer-file-name)
1776 (not diff-apply-hunk-to-backup-file)
1777 (not (set (make-local-variable 'diff-apply-hunk-to-backup-file)
1778 (yes-or-no-p (format "Really apply this hunk to %s? "
1779 (file-name-nondirectory
1780 buffer-file-name)))))))
1781 (error "%s"
1782 (substitute-command-keys
1783 (format "Use %s\\[diff-apply-hunk] to apply it to the other file"
1784 (if (not reverse) "\\[universal-argument] ")))))
1785 ((and switched
1786 ;; A reversed patch was detected, perhaps apply it in reverse.
1787 (not (save-window-excursion
1788 (pop-to-buffer buf)
1789 (goto-char (+ (car pos) (cdr old)))
1790 (y-or-n-p
1791 (if reverse
1792 "Hunk hasn't been applied yet; apply it now? "
1793 "Hunk has already been applied; undo it? ")))))
1794 (message "(Nothing done)"))
1796 ;; Apply the hunk
1797 (with-current-buffer buf
1798 (goto-char (car pos))
1799 (delete-region (car pos) (cdr pos))
1800 (insert (car new)))
1801 ;; Display BUF in a window
1802 (set-window-point (display-buffer buf) (+ (car pos) (cdr new)))
1803 (diff-hunk-status-msg line-offset (diff-xor switched reverse) nil)
1804 (when diff-advance-after-apply-hunk
1805 (diff-hunk-next))))))
1808 (defun diff-test-hunk (&optional reverse)
1809 "See whether it's possible to apply the current hunk.
1810 With a prefix argument, try to REVERSE the hunk."
1811 (interactive "P")
1812 (pcase-let ((`(,buf ,line-offset ,pos ,src ,_dst ,switched)
1813 (diff-find-source-location nil reverse)))
1814 (set-window-point (display-buffer buf) (+ (car pos) (cdr src)))
1815 (diff-hunk-status-msg line-offset (diff-xor reverse switched) t)))
1818 (defalias 'diff-mouse-goto-source 'diff-goto-source)
1820 (defun diff-goto-source (&optional other-file event)
1821 "Jump to the corresponding source line.
1822 `diff-jump-to-old-file' (or its opposite if the OTHER-FILE prefix arg
1823 is given) determines whether to jump to the old or the new file.
1824 If the prefix arg is bigger than 8 (for example with \\[universal-argument] \\[universal-argument])
1825 then `diff-jump-to-old-file' is also set, for the next invocations."
1826 (interactive (list current-prefix-arg last-input-event))
1827 ;; When pointing at a removal line, we probably want to jump to
1828 ;; the old location, and else to the new (i.e. as if reverting).
1829 ;; This is a convenient detail when using smerge-diff.
1830 (if event (posn-set-point (event-end event)))
1831 (let ((rev (not (save-excursion (beginning-of-line) (looking-at "[-<]")))))
1832 (pcase-let ((`(,buf ,line-offset ,pos ,src ,_dst ,switched)
1833 (diff-find-source-location other-file rev)))
1834 (pop-to-buffer buf)
1835 (goto-char (+ (car pos) (cdr src)))
1836 (diff-hunk-status-msg line-offset (diff-xor rev switched) t))))
1839 (defun diff-current-defun ()
1840 "Find the name of function at point.
1841 For use in `add-log-current-defun-function'."
1842 ;; Kill change-log-default-name so it gets recomputed each time, since
1843 ;; each hunk may belong to another file which may belong to another
1844 ;; directory and hence have a different ChangeLog file.
1845 (kill-local-variable 'change-log-default-name)
1846 (save-excursion
1847 (when (looking-at diff-hunk-header-re)
1848 (forward-line 1)
1849 (re-search-forward "^[^ ]" nil t))
1850 (pcase-let ((`(,buf ,_line-offset ,pos ,src ,dst ,switched)
1851 (ignore-errors ;Signals errors in place of prompting.
1852 ;; Use `noprompt' since this is used in which-func-mode
1853 ;; and such.
1854 (diff-find-source-location nil nil 'noprompt))))
1855 (when buf
1856 (beginning-of-line)
1857 (or (when (memq (char-after) '(?< ?-))
1858 ;; Cursor is pointing at removed text. This could be a removed
1859 ;; function, in which case, going to the source buffer will
1860 ;; not help since the function is now removed. Instead,
1861 ;; try to figure out the function name just from the
1862 ;; code-fragment.
1863 (let ((old (if switched dst src)))
1864 (with-temp-buffer
1865 (insert (car old))
1866 (funcall (buffer-local-value 'major-mode buf))
1867 (goto-char (+ (point-min) (cdr old)))
1868 (add-log-current-defun))))
1869 (with-current-buffer buf
1870 (goto-char (+ (car pos) (cdr src)))
1871 (add-log-current-defun)))))))
1873 (defun diff-ignore-whitespace-hunk ()
1874 "Re-diff the current hunk, ignoring whitespace differences."
1875 (interactive)
1876 (let* ((char-offset (- (point) (diff-beginning-of-hunk t)))
1877 (opts (pcase (char-after) (?@ "-bu") (?* "-bc") (_ "-b")))
1878 (line-nb (and (or (looking-at "[^0-9]+\\([0-9]+\\)")
1879 (error "Can't find line number"))
1880 (string-to-number (match-string 1))))
1881 (inhibit-read-only t)
1882 (hunk (delete-and-extract-region
1883 (point) (save-excursion (diff-end-of-hunk) (point))))
1884 (lead (make-string (1- line-nb) ?\n)) ;Line nums start at 1.
1885 (file1 (make-temp-file "diff1"))
1886 (file2 (make-temp-file "diff2"))
1887 (coding-system-for-read buffer-file-coding-system)
1888 old new)
1889 (unwind-protect
1890 (save-excursion
1891 (setq old (diff-hunk-text hunk nil char-offset))
1892 (setq new (diff-hunk-text hunk t char-offset))
1893 (write-region (concat lead (car old)) nil file1 nil 'nomessage)
1894 (write-region (concat lead (car new)) nil file2 nil 'nomessage)
1895 (with-temp-buffer
1896 (let ((status
1897 (call-process diff-command nil t nil
1898 opts file1 file2)))
1899 (pcase status
1900 (0 nil) ;Nothing to reformat.
1901 (1 (goto-char (point-min))
1902 ;; Remove the file-header.
1903 (when (re-search-forward diff-hunk-header-re nil t)
1904 (delete-region (point-min) (match-beginning 0))))
1905 (_ (goto-char (point-max))
1906 (unless (bolp) (insert "\n"))
1907 (insert hunk)))
1908 (setq hunk (buffer-string))
1909 (unless (memq status '(0 1))
1910 (error "Diff returned: %s" status)))))
1911 ;; Whatever happens, put back some equivalent text: either the new
1912 ;; one or the original one in case some error happened.
1913 (insert hunk)
1914 (delete-file file1)
1915 (delete-file file2))))
1917 ;;; Fine change highlighting.
1919 (defface diff-refine-change
1920 '((((class color) (min-colors 88) (background light))
1921 :background "#ffff55")
1922 (((class color) (min-colors 88) (background dark))
1923 :background "#aaaa22")
1924 (t :inverse-video t))
1925 "Face used for char-based changes shown by `diff-refine-hunk'."
1926 :group 'diff-mode)
1928 (defface diff-refine-removed
1929 '((default
1930 :inherit diff-refine-change)
1931 (((class color) (min-colors 88) (background light))
1932 :background "#ffbbbb")
1933 (((class color) (min-colors 88) (background dark))
1934 :background "#aa2222"))
1935 "Face used for removed characters shown by `diff-refine-hunk'."
1936 :group 'diff-mode
1937 :version "24.3")
1939 (defface diff-refine-added
1940 '((default
1941 :inherit diff-refine-change)
1942 (((class color) (min-colors 88) (background light))
1943 :background "#aaffaa")
1944 (((class color) (min-colors 88) (background dark))
1945 :background "#22aa22"))
1946 "Face used for added characters shown by `diff-refine-hunk'."
1947 :group 'diff-mode
1948 :version "24.3")
1950 (defun diff-refine-preproc ()
1951 (while (re-search-forward "^[+>]" nil t)
1952 ;; Remove spurious changes due to the fact that one side of the hunk is
1953 ;; marked with leading + or > and the other with leading - or <.
1954 ;; We used to replace all the prefix chars with " " but this only worked
1955 ;; when we did char-based refinement (or when using
1956 ;; smerge-refine-weight-hack) since otherwise, the `forward' motion done
1957 ;; in chopup do not necessarily do the same as the ones in highlight
1958 ;; since the "_" is not treated the same as " ".
1959 (replace-match (cdr (assq (char-before) '((?+ . "-") (?> . "<"))))))
1962 (declare-function smerge-refine-subst "smerge-mode"
1963 (beg1 end1 beg2 end2 props-c &optional preproc props-r props-a))
1965 (defun diff-refine-hunk ()
1966 "Highlight changes of hunk at point at a finer granularity."
1967 (interactive)
1968 (require 'smerge-mode)
1969 (save-excursion
1970 (diff-beginning-of-hunk t)
1971 (let* ((start (point))
1972 (style (diff-hunk-style)) ;Skips the hunk header as well.
1973 (beg (point))
1974 (props-c '((diff-mode . fine) (face diff-refine-change)))
1975 (props-r '((diff-mode . fine) (face diff-refine-removed)))
1976 (props-a '((diff-mode . fine) (face diff-refine-added)))
1977 ;; Be careful to go back to `start' so diff-end-of-hunk gets
1978 ;; to read the hunk header's line info.
1979 (end (progn (goto-char start) (diff-end-of-hunk) (point))))
1981 (remove-overlays beg end 'diff-mode 'fine)
1983 (goto-char beg)
1984 (pcase style
1985 (`unified
1986 (while (re-search-forward
1987 (eval-when-compile
1988 (let ((no-LF-at-eol-re "\\(?:\\\\.*\n\\)?"))
1989 (concat "^\\(?:-.*\n\\)+" no-LF-at-eol-re
1990 "\\(\\)"
1991 "\\(?:\\+.*\n\\)+" no-LF-at-eol-re)))
1992 end t)
1993 (smerge-refine-subst (match-beginning 0) (match-end 1)
1994 (match-end 1) (match-end 0)
1995 nil 'diff-refine-preproc props-r props-a)))
1996 (`context
1997 (let* ((middle (save-excursion (re-search-forward "^---")))
1998 (other middle))
1999 (while (re-search-forward "^\\(?:!.*\n\\)+" middle t)
2000 (smerge-refine-subst (match-beginning 0) (match-end 0)
2001 (save-excursion
2002 (goto-char other)
2003 (re-search-forward "^\\(?:!.*\n\\)+" end)
2004 (setq other (match-end 0))
2005 (match-beginning 0))
2006 other
2007 (if diff-use-changed-face props-c)
2008 'diff-refine-preproc
2009 (unless diff-use-changed-face props-r)
2010 (unless diff-use-changed-face props-a)))))
2011 (_ ;; Normal diffs.
2012 (let ((beg1 (1+ (point))))
2013 (when (re-search-forward "^---.*\n" end t)
2014 ;; It's a combined add&remove, so there's something to do.
2015 (smerge-refine-subst beg1 (match-beginning 0)
2016 (match-end 0) end
2017 nil 'diff-refine-preproc props-r props-a))))))))
2019 (defun diff-undo (&optional arg)
2020 "Perform `undo', ignoring the buffer's read-only status."
2021 (interactive "P")
2022 (let ((inhibit-read-only t))
2023 (undo arg)))
2025 (defun diff-add-change-log-entries-other-window ()
2026 "Iterate through the current diff and create ChangeLog entries.
2027 I.e. like `add-change-log-entry-other-window' but applied to all hunks."
2028 (interactive)
2029 ;; XXX: Currently add-change-log-entry-other-window is only called
2030 ;; once per hunk. Some hunks have multiple changes, it would be
2031 ;; good to call it for each change.
2032 (save-excursion
2033 (goto-char (point-min))
2034 (condition-case nil
2035 ;; Call add-change-log-entry-other-window for each hunk in
2036 ;; the diff buffer.
2037 (while (progn
2038 (diff-hunk-next)
2039 ;; Move to where the changes are,
2040 ;; `add-change-log-entry-other-window' works better in
2041 ;; that case.
2042 (re-search-forward
2043 (concat "\n[!+-<>]"
2044 ;; If the hunk is a context hunk with an empty first
2045 ;; half, recognize the "--- NNN,MMM ----" line
2046 "\\(-- [0-9]+\\(,[0-9]+\\)? ----\n"
2047 ;; and skip to the next non-context line.
2048 "\\( .*\n\\)*[+]\\)?")
2049 nil t))
2050 (save-excursion
2051 ;; FIXME: this pops up windows of all the buffers.
2052 (add-change-log-entry nil nil t nil t)))
2053 ;; When there's no more hunks, diff-hunk-next signals an error.
2054 (error nil))))
2056 (defun diff-delete-trailing-whitespace (&optional other-file)
2057 "Remove trailing whitespace from lines modified in this diff.
2058 This edits both the current Diff mode buffer and the patched
2059 source file(s). If `diff-jump-to-old-file' is non-nil, edit the
2060 original (unpatched) source file instead. With a prefix argument
2061 OTHER-FILE, flip the choice of which source file to edit.
2063 If a file referenced in the diff has no buffer and needs to be
2064 fixed, visit it in a buffer."
2065 (interactive "P")
2066 (save-excursion
2067 (goto-char (point-min))
2068 (let* ((other (diff-xor other-file diff-jump-to-old-file))
2069 (modified-buffers nil)
2070 (style (save-excursion
2071 (when (re-search-forward diff-hunk-header-re nil t)
2072 (goto-char (match-beginning 0))
2073 (diff-hunk-style))))
2074 (regexp (concat "^[" (if other "-<" "+>") "!]"
2075 (if (eq style 'context) " " "")
2076 ".*?\\([ \t]+\\)$"))
2077 (inhibit-read-only t)
2078 (end-marker (make-marker))
2079 hunk-end)
2080 ;; Move to the first hunk.
2081 (re-search-forward diff-hunk-header-re nil 1)
2082 (while (progn (save-excursion
2083 (re-search-forward diff-hunk-header-re nil 1)
2084 (setq hunk-end (point)))
2085 (< (point) hunk-end))
2086 ;; For context diffs, search only in the appropriate half of
2087 ;; the hunk. For other diffs, search within the entire hunk.
2088 (if (not (eq style 'context))
2089 (set-marker end-marker hunk-end)
2090 (let ((mid-hunk
2091 (save-excursion
2092 (re-search-forward diff-context-mid-hunk-header-re hunk-end)
2093 (point))))
2094 (if other
2095 (set-marker end-marker mid-hunk)
2096 (goto-char mid-hunk)
2097 (set-marker end-marker hunk-end))))
2098 (while (re-search-forward regexp end-marker t)
2099 (let ((match-data (match-data)))
2100 (pcase-let ((`(,buf ,line-offset ,pos ,src ,_dst ,_switched)
2101 (diff-find-source-location other-file)))
2102 (when line-offset
2103 ;; Remove the whitespace in the Diff mode buffer.
2104 (set-match-data match-data)
2105 (replace-match "" t t nil 1)
2106 ;; Remove the whitespace in the source buffer.
2107 (with-current-buffer buf
2108 (save-excursion
2109 (goto-char (+ (car pos) (cdr src)))
2110 (beginning-of-line)
2111 (when (re-search-forward "\\([ \t]+\\)$" (line-end-position) t)
2112 (unless (memq buf modified-buffers)
2113 (push buf modified-buffers))
2114 (replace-match ""))))))))
2115 (goto-char hunk-end))
2116 (if modified-buffers
2117 (message "Deleted trailing whitespace from %s."
2118 (mapconcat (lambda (buf) (concat "`" (buffer-name buf) "'"))
2119 modified-buffers ", "))
2120 (message "No trailing whitespace to delete.")))))
2122 ;; provide the package
2123 (provide 'diff-mode)
2125 ;;; Old Change Log from when diff-mode wasn't part of Emacs:
2126 ;; Revision 1.11 1999/10/09 23:38:29 monnier
2127 ;; (diff-mode-load-hook): dropped.
2128 ;; (auto-mode-alist): also catch *.diffs.
2129 ;; (diff-find-file-name, diff-mode): add smarts to find the right file
2130 ;; for *.rej files (that lack any file name indication).
2132 ;; Revision 1.10 1999/09/30 15:32:11 monnier
2133 ;; added support for "\ No newline at end of file".
2135 ;; Revision 1.9 1999/09/15 00:01:13 monnier
2136 ;; - added basic `compile' support.
2137 ;; - have diff-kill-hunk call diff-kill-file if it's the only hunk.
2138 ;; - diff-kill-file now tries to kill the leading garbage as well.
2140 ;; Revision 1.8 1999/09/13 21:10:09 monnier
2141 ;; - don't use CL in the autoloaded code
2142 ;; - accept diffs using -T
2144 ;; Revision 1.7 1999/09/05 20:53:03 monnier
2145 ;; interface to ediff-patch
2147 ;; Revision 1.6 1999/09/01 20:55:13 monnier
2148 ;; (ediff=patch-file): add bindings to call ediff-patch.
2149 ;; (diff-find-file-name): taken out of diff-goto-source.
2150 ;; (diff-unified->context, diff-context->unified, diff-reverse-direction,
2151 ;; diff-fixup-modifs): only use the region if a prefix arg is given.
2153 ;; Revision 1.5 1999/08/31 19:18:52 monnier
2154 ;; (diff-beginning-of-file, diff-prev-file): fixed wrong parenthesis.
2156 ;; Revision 1.4 1999/08/31 13:01:44 monnier
2157 ;; use `combine-after-change-calls' to minimize the slowdown of font-lock.
2160 ;;; diff-mode.el ends here