| blob | 940457b6cc085af2d4ae0c03722214d735f9d490 |
1 ;;; diff-mode.el --- a mode for viewing/editing context diffs -*- lexical-binding: t -*-
3 ;; Copyright (C) 1998-2013 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.
41 ;;
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.
44 ;;
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.
50 ;;
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:
62 "Major mode for viewing/editing diffs."
68 "If non-nil, `diff-mode' buffers default to being read-only."
73 "Non-nil means `diff-goto-source' jumps to the old file.
74 Else, it jumps to the new file."
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)."
89 "Non-nil means `diff-apply-hunk' will move to the next hunk after applying."
94 "Run after setting up the `diff-mode' major mode."
105 ;;;;
106 ;;;; keymap, menu, ...
107 ;;;;
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 ("/" . diff-undo)
128 ([remap undo] . diff-undo))
129 "Basic keymap for `diff-mode', bound to various prefix keys."
130 :inherit special-mode-map)
132 (easy-mmode-defmap diff-mode-map
133 `(("\e" . ,(let ((map (make-sparse-keymap)))
134 ;; We want to inherit most bindings from diff-mode-shared-map,
135 ;; but not all since they may hide useful M-<foo> global
136 ;; bindings when editing.
137 (set-keymap-parent map diff-mode-shared-map)
138 (dolist (key '("A" "r" "R" "g" "q" "W" "z"))
139 (define-key map key nil))
140 map))
141 ;; From compilation-minor-mode.
142 ("\C-c\C-c" . diff-goto-source)
143 ;; By analogy with the global C-x 4 a binding.
144 ("\C-x4A" . diff-add-change-log-entries-other-window)
145 ;; Misc operations.
146 ("\C-c\C-a" . diff-apply-hunk)
147 ("\C-c\C-e" . diff-ediff-patch)
148 ("\C-c\C-n" . diff-restrict-view)
149 ("\C-c\C-s" . diff-split-hunk)
150 ("\C-c\C-t" . diff-test-hunk)
151 ("\C-c\C-r" . diff-reverse-direction)
152 ("\C-c\C-u" . diff-context->unified)
153 ;; `d' because it duplicates the context :-( --Stef
154 ("\C-c\C-d" . diff-unified->context)
155 ("\C-c\C-w" . diff-ignore-whitespace-hunk)
156 ("\C-c\C-b" . diff-refine-hunk) ;No reason for `b' :-(
157 ("\C-c\C-f" . next-error-follow-minor-mode))
158 "Keymap for `diff-mode'. See also `diff-mode-shared-map'.")
160 (easy-menu-define diff-mode-menu diff-mode-map
161 "Menu for `diff-mode'."
162 '("Diff"
163 ["Jump to Source" diff-goto-source
164 :help "Jump to the corresponding source line"]
165 ["Apply hunk" diff-apply-hunk
166 :help "Apply the current hunk to the source file and go to the next"]
167 ["Test applying hunk" diff-test-hunk
168 :help "See whether it's possible to apply the current hunk"]
169 ["Apply diff with Ediff" diff-ediff-patch
170 :help "Call `ediff-patch-file' on the current buffer"]
171 ["Create Change Log entries" diff-add-change-log-entries-other-window
172 :help "Create ChangeLog entries for the changes in the diff buffer"]
173 "-----"
174 ["Reverse direction" diff-reverse-direction
175 :help "Reverse the direction of the diffs"]
176 ["Context -> Unified" diff-context->unified
177 :help "Convert context diffs to unified diffs"]
178 ["Unified -> Context" diff-unified->context
179 :help "Convert unified diffs to context diffs"]
180 ;;["Fixup Headers" diff-fixup-modifs (not buffer-read-only)]
181 ["Remove trailing whitespace" diff-delete-trailing-whitespace
182 :help "Remove trailing whitespace problems introduced by the diff"]
183 ["Show trailing whitespace" whitespace-mode
184 :style toggle :selected (bound-and-true-p whitespace-mode)
185 :help "Show trailing whitespace in modified lines"]
186 "-----"
187 ["Split hunk" diff-split-hunk
188 :active (diff-splittable-p)
189 :help "Split the current (unified diff) hunk at point into two hunks"]
190 ["Ignore whitespace changes" diff-ignore-whitespace-hunk
191 :help "Re-diff the current hunk, ignoring whitespace differences"]
192 ["Highlight fine changes" diff-refine-hunk
193 :help "Highlight changes of hunk at point at a finer granularity"]
194 ["Kill current hunk" diff-hunk-kill
195 :help "Kill current hunk"]
196 ["Kill current file's hunks" diff-file-kill
197 :help "Kill all current file's hunks"]
198 "-----"
199 ["Previous Hunk" diff-hunk-prev
200 :help "Go to the previous count'th hunk"]
201 ["Next Hunk" diff-hunk-next
202 :help "Go to the next count'th hunk"]
203 ["Previous File" diff-file-prev
204 :help "Go to the previous count'th file"]
205 ["Next File" diff-file-next
206 :help "Go to the next count'th file"]
207 ))
209 (defcustom diff-minor-mode-prefix "\C-c="
210 "Prefix key for `diff-minor-mode' commands."
211 :type '(choice (string "\e") (string "C-c=") string)
212 :group 'diff-mode)
214 (easy-mmode-defmap diff-minor-mode-map
215 `((,diff-minor-mode-prefix . ,diff-mode-shared-map))
216 "Keymap for `diff-minor-mode'. See also `diff-mode-shared-map'.")
218 (define-minor-mode diff-auto-refine-mode
219 "Toggle automatic diff hunk highlighting (Diff Auto Refine mode).
220 With a prefix argument ARG, enable Diff Auto Refine mode if ARG
221 is positive, and disable it otherwise. If called from Lisp,
222 enable the mode if ARG is omitted or nil.
224 Diff Auto Refine mode is a buffer-local minor mode used with
225 `diff-mode'. When enabled, Emacs automatically highlights
226 changes in detail as the user visits hunks. When transitioning
227 from disabled to enabled, it tries to refine the current hunk, as
228 well."
229 :group 'diff-mode :init-value t :lighter nil ;; " Auto-Refine"
230 (when diff-auto-refine-mode
231 (condition-case-unless-debug nil (diff-refine-hunk) (error nil))))
233 ;;;;
234 ;;;; font-lock support
235 ;;;;
237 (defface diff-header
238 '((((class color) (min-colors 88) (background light))
239 :background "grey80")
240 (((class color) (min-colors 88) (background dark))
241 :background "grey45")
242 (((class color))
243 :foreground "blue1" :weight bold)
244 (t :weight bold))
245 "`diff-mode' face inherited by hunk and index header faces."
246 :group 'diff-mode)
247 (define-obsolete-face-alias 'diff-header-face 'diff-header "22.1")
248 (defvar diff-header-face 'diff-header)
250 (defface diff-file-header
251 '((((class color) (min-colors 88) (background light))
252 :background "grey70" :weight bold)
253 (((class color) (min-colors 88) (background dark))
254 :background "grey60" :weight bold)
255 (((class color))
256 :foreground "cyan" :weight bold)
257 (t :weight bold)) ; :height 1.3
258 "`diff-mode' face used to highlight file header lines."
259 :group 'diff-mode)
260 (define-obsolete-face-alias 'diff-file-header-face 'diff-file-header "22.1")
261 (defvar diff-file-header-face 'diff-file-header)
263 (defface diff-index
264 '((t :inherit diff-file-header))
265 "`diff-mode' face used to highlight index header lines."
266 :group 'diff-mode)
267 (define-obsolete-face-alias 'diff-index-face 'diff-index "22.1")
268 (defvar diff-index-face 'diff-index)
270 (defface diff-hunk-header
271 '((t :inherit diff-header))
272 "`diff-mode' face used to highlight hunk header lines."
273 :group 'diff-mode)
274 (define-obsolete-face-alias 'diff-hunk-header-face 'diff-hunk-header "22.1")
275 (defvar diff-hunk-header-face 'diff-hunk-header)
277 (defface diff-removed
278 '((default
279 :inherit diff-changed)
280 (((class color) (min-colors 88) (background light))
281 :background "#ffdddd")
282 (((class color) (min-colors 88) (background dark))
283 :background "#553333")
284 (((class color))
285 :foreground "red"))
286 "`diff-mode' face used to highlight removed lines."
287 :group 'diff-mode)
288 (define-obsolete-face-alias 'diff-removed-face 'diff-removed "22.1")
289 (defvar diff-removed-face 'diff-removed)
291 (defface diff-added
292 '((default
293 :inherit diff-changed)
294 (((class color) (min-colors 88) (background light))
295 :background "#ddffdd")
296 (((class color) (min-colors 88) (background dark))
297 :background "#335533")
298 (((class color))
299 :foreground "green"))
300 "`diff-mode' face used to highlight added lines."
301 :group 'diff-mode)
302 (define-obsolete-face-alias 'diff-added-face 'diff-added "22.1")
303 (defvar diff-added-face 'diff-added)
305 (defface diff-changed
306 ;; We normally apply a `shadow'-based face on the `diff-context'
307 ;; face, and keep `diff-changed' the default.
308 '((((class color grayscale) (min-colors 88)))
309 ;; If the terminal lacks sufficient colors for shadowing,
310 ;; highlight changed lines explicitly.
311 (((class color))
312 :foreground "yellow"))
313 "`diff-mode' face used to highlight changed lines."
314 :group 'diff-mode)
315 (define-obsolete-face-alias 'diff-changed-face 'diff-changed "22.1")
316 (defvar diff-changed-face 'diff-changed)
318 (defface diff-indicator-removed
319 '((t :inherit diff-removed))
320 "`diff-mode' face used to highlight indicator of removed lines (-, <)."
321 :group 'diff-mode
322 :version "22.1")
323 (defvar diff-indicator-removed-face 'diff-indicator-removed)
325 (defface diff-indicator-added
326 '((t :inherit diff-added))
327 "`diff-mode' face used to highlight indicator of added lines (+, >)."
328 :group 'diff-mode
329 :version "22.1")
330 (defvar diff-indicator-added-face 'diff-indicator-added)
332 (defface diff-indicator-changed
333 '((t :inherit diff-changed))
334 "`diff-mode' face used to highlight indicator of changed lines."
335 :group 'diff-mode
336 :version "22.1")
337 (defvar diff-indicator-changed-face 'diff-indicator-changed)
339 (defface diff-function
340 '((t :inherit diff-header))
342 :group 'diff-mode)
343 (define-obsolete-face-alias 'diff-function-face 'diff-function "22.1")
344 (defvar diff-function-face 'diff-function)
346 (defface diff-context
347 '((((class color grayscale) (min-colors 88)) :inherit shadow))
348 "`diff-mode' face used to highlight context and other side-information."
349 :group 'diff-mode)
350 (define-obsolete-face-alias 'diff-context-face 'diff-context "22.1")
351 (defvar diff-context-face 'diff-context)
353 (defface diff-nonexistent
354 '((t :inherit diff-file-header))
355 "`diff-mode' face used to highlight nonexistent files in recursive diffs."
356 :group 'diff-mode)
357 (define-obsolete-face-alias 'diff-nonexistent-face 'diff-nonexistent "22.1")
358 (defvar diff-nonexistent-face 'diff-nonexistent)
360 (defconst diff-yank-handler '(diff-yank-function))
361 (defun diff-yank-function (text)
362 ;; FIXME: the yank-handler is now called separately on each piece of text
363 ;; with a yank-handler property, so the next-single-property-change call
364 ;; below will always return nil :-( --stef
365 (let ((mixed (next-single-property-change 0 'yank-handler text))
366 (start (point)))
367 ;; First insert the text.
368 (insert text)
369 ;; If the text does not include any diff markers and if we're not
370 ;; yanking back into a diff-mode buffer, get rid of the prefixes.
371 (unless (or mixed (derived-mode-p 'diff-mode))
372 (undo-boundary) ; Just in case the user wanted the prefixes.
373 (let ((re (save-excursion
375 (if (eq (char-after) ?!)
377 "^[ <>!+-]"))))
378 (save-excursion
379 (while (re-search-backward re start t)
380 (replace-match "" t t)))))))
382 (defconst diff-hunk-header-re-unified
384 (defconst diff-context-mid-hunk-header-re
387 (defvar diff-use-changed-face (and (face-differs-from-default-p diff-changed-face)
388 (not (face-equal diff-changed-face diff-added-face))
389 (not (face-equal diff-changed-face diff-removed-face)))
390 "If non-nil, use the face `diff-changed' for changed lines in context diffs.
391 Otherwise, use the face `diff-removed' for removed lines,
392 and the face `diff-added' for added lines.")
394 (defvar diff-font-lock-keywords
396 (1 diff-hunk-header-face) (6 diff-function-face))
398 (1 diff-hunk-header-face) (2 diff-function-face))
400 (,diff-context-mid-hunk-header-re . diff-hunk-header-face) ;context
401 ("^[0-9,]+[acd][0-9,]+$" . diff-hunk-header-face) ;normal
402 ("^---$" . diff-hunk-header-face) ;normal
403 ;; For file headers, accept files with spaces, but be careful to rule
404 ;; out false-positives when matching hunk headers.
405 ("^\\(---\\|\\+\\+\\+\\|\\*\\*\\*\\) \\([^\t\n]+?\\)\\(?:\t.*\\| \\(\\*\\*\\*\\*\\|----\\)\\)?\n"
406 (0 diff-header-face)
407 (2 (if (not (match-end 3)) diff-file-header-face) prepend))
409 (1 diff-indicator-removed-face) (2 diff-removed-face))
411 (1 diff-indicator-added-face) (2 diff-added-face))
413 (1 (if diff-use-changed-face
414 diff-indicator-changed-face
415 ;; Otherwise, search for `diff-context-mid-hunk-header-re' and
416 ;; if the line of context diff is above, use `diff-removed-face';
417 ;; if below, use `diff-added-face'.
418 (save-match-data
419 (let ((limit (save-excursion (diff-beginning-of-hunk))))
420 (if (save-excursion (re-search-backward diff-context-mid-hunk-header-re limit t))
421 diff-indicator-added-face
422 diff-indicator-removed-face)))))
423 (2 (if diff-use-changed-face
424 diff-changed-face
425 ;; Otherwise, use the same method as above.
426 (save-match-data
427 (let ((limit (save-excursion (diff-beginning-of-hunk))))
428 (if (save-excursion (re-search-backward diff-context-mid-hunk-header-re limit t))
429 diff-added-face
430 diff-removed-face))))))
432 (0 diff-header-face) (1 diff-index-face prepend))
435 (1 font-lock-comment-delimiter-face)
436 (2 font-lock-comment-face))
439 (defconst diff-font-lock-defaults
440 '(diff-font-lock-keywords t nil nil nil (font-lock-multiline . nil)))
442 (defvar diff-imenu-generic-expression
443 ;; Prefer second name as first is most likely to be a backup or
445 ;; catches Debian source diff files (which lack the trailing date).
449 ;;;;
450 ;;;; Movement
451 ;;;;
453 (defvar diff-valid-unified-empty-line t
454 "If non-nil, empty lines are valid in unified diffs.
455 Some versions of diff replace all-blank context lines in unified format with
456 empty lines. This makes the format less robust, but is tolerated.
457 See http://lists.gnu.org/archive/html/emacs-devel/2007-11/msg01990.html")
459 (defconst diff-hunk-header-re
460 (concat "^\\(?:" diff-hunk-header-re-unified ".*\\|\\*\\{15\\}.*\n\\*\\*\\* .+ \\*\\*\\*\\*\\|[0-9]+\\(,[0-9]+\\)?[acd][0-9]+\\(,[0-9]+\\)?\\)$"))
461 (defconst diff-file-header-re (concat "^\\(--- .+\n\\+\\+\\+ \\|\\*\\*\\* .+\n--- \\|[^-+!<>0-9@* \n]\\).+\n" (substring diff-hunk-header-re 1)))
462 (defvar diff-narrowed-to nil)
464 (defun diff-hunk-style (&optional style)
465 (when (looking-at diff-hunk-header-re)
466 (setq style (cdr (assq (char-after) '((?@ . unified) (?* . context)))))
467 (goto-char (match-end 0)))
468 style)
470 (defun diff-end-of-hunk (&optional style donttrustheader)
471 "Advance to the end of the current hunk, and return its position."
472 (let (end)
473 (when (looking-at diff-hunk-header-re)
474 ;; Especially important for unified (because headers are ambiguous).
475 (setq style (diff-hunk-style style))
476 (goto-char (match-end 0))
477 (when (and (not donttrustheader) (match-end 2))
478 (let* ((nold (string-to-number (or (match-string 2) "1")))
479 (nnew (string-to-number (or (match-string 4) "1")))
480 (endold
481 (save-excursion
482 (re-search-forward (if diff-valid-unified-empty-line
484 nil t nold)
485 (line-beginning-position
486 ;; Skip potential "\ No newline at end of file".
488 (endnew
489 ;; The hunk may end with a bunch of "+" lines, so the `end' is
490 ;; then further than computed above.
491 (save-excursion
492 (re-search-forward (if diff-valid-unified-empty-line
494 nil t nnew)
495 (line-beginning-position
496 ;; Skip potential "\ No newline at end of file".
498 (setq end (max endold endnew)))))
499 ;; We may have a first evaluation of `end' thanks to the hunk header.
500 (unless end
501 (setq end (and (re-search-forward
502 (pcase style
503 (`unified
504 (concat (if diff-valid-unified-empty-line
506 ;; A `unified' header is ambiguous.
507 diff-file-header-re))
511 nil t)
512 (match-beginning 0)))
513 (when diff-valid-unified-empty-line
514 ;; While empty lines may be valid inside hunks, they are also likely
515 ;; to be unrelated to the hunk.
516 (goto-char (or end (point-max)))
518 (forward-char -1)
519 (setq end (point)))))
520 ;; The return value is used by easy-mmode-define-navigation.
521 (goto-char (or end (point-max)))))
523 (defun diff-beginning-of-hunk (&optional try-harder)
524 "Move back to the previous hunk beginning, and return its position.
525 If point is in a file header rather than a hunk, advance to the
526 next hunk if TRY-HARDER is non-nil; otherwise signal an error."
527 (beginning-of-line)
528 (if (looking-at diff-hunk-header-re)
529 (point)
530 (forward-line 1)
531 (condition-case ()
532 (re-search-backward diff-hunk-header-re)
533 (error
534 (unless try-harder
535 (error "Can't find the beginning of the hunk"))
536 (diff-beginning-of-file-and-junk)
537 (diff-hunk-next)
538 (point)))))
540 (defun diff-unified-hunk-p ()
541 (save-excursion
542 (ignore-errors
543 (diff-beginning-of-hunk)
544 (looking-at "^@@"))))
546 (defun diff-beginning-of-file ()
547 (beginning-of-line)
548 (unless (looking-at diff-file-header-re)
549 (let ((start (point))
550 res)
551 ;; diff-file-header-re may need to match up to 4 lines, so in case
552 ;; we're inside the header, we need to move up to 3 lines forward.
553 (forward-line 3)
554 (if (and (setq res (re-search-backward diff-file-header-re nil t))
555 ;; Maybe the 3 lines forward were too much and we matched
556 ;; a file header after our starting point :-(
557 (or (<= (point) start)
558 (setq res (re-search-backward diff-file-header-re nil t))))
559 res
560 (goto-char start)
561 (error "Can't find the beginning of the file")))))
564 (defun diff-end-of-file ()
567 nil 'move)
568 (if (match-beginning 1)
569 (goto-char (match-beginning 1))
570 (beginning-of-line)))
572 (defvar diff--auto-refine-data nil)
574 ;; Define diff-{hunk,file}-{prev,next}
575 (easy-mmode-define-navigation
576 diff-hunk diff-hunk-header-re "hunk" diff-end-of-hunk diff-restrict-view
577 (when diff-auto-refine-mode
578 (unless (prog1 diff--auto-refine-data
579 (setq diff--auto-refine-data
580 (cons (current-buffer) (point-marker))))
581 (run-at-time 0.0 nil
582 (lambda ()
583 (when diff--auto-refine-data
584 (let ((buffer (car diff--auto-refine-data))
585 (point (cdr diff--auto-refine-data)))
586 (setq diff--auto-refine-data nil)
587 (with-local-quit
588 (when (buffer-live-p buffer)
589 (with-current-buffer buffer
590 (save-excursion
591 (goto-char point)
592 (diff-refine-hunk))))))))))))
594 (easy-mmode-define-navigation
595 diff-file diff-file-header-re "file" diff-end-of-file)
597 (defun diff-bounds-of-hunk ()
598 "Return the bounds of the diff hunk at point.
599 The return value is a list (BEG END), which are the hunk's start
600 and end positions. Signal an error if no hunk is found. If
601 point is in a file header, return the bounds of the next hunk."
602 (save-excursion
603 (let ((pos (point))
604 (beg (diff-beginning-of-hunk t))
605 (end (diff-end-of-hunk)))
606 (cond ((>= end pos)
607 (list beg end))
608 ;; If this hunk ends above POS, consider the next hunk.
609 ((re-search-forward diff-hunk-header-re nil t)
610 (list (match-beginning 0) (diff-end-of-hunk)))
611 (t (error "No hunk found"))))))
613 (defun diff-bounds-of-file ()
614 "Return the bounds of the file segment at point.
615 The return value is a list (BEG END), which are the segment's
616 start and end positions."
617 (save-excursion
618 (let ((pos (point))
619 (beg (progn (diff-beginning-of-file-and-junk)
620 (point))))
621 (diff-end-of-file)
622 ;; bzr puts a newline after the last hunk.
624 (forward-char 1))
625 (if (> pos (point))
626 (error "Not inside a file diff"))
627 (list beg (point)))))
629 (defun diff-restrict-view (&optional arg)
630 "Restrict the view to the current hunk.
631 If the prefix ARG is given, restrict the view to the current file instead."
632 (interactive "P")
633 (apply 'narrow-to-region
634 (if arg (diff-bounds-of-file) (diff-bounds-of-hunk)))
635 (set (make-local-variable 'diff-narrowed-to) (if arg 'file 'hunk)))
637 (defun diff-hunk-kill ()
638 "Kill the hunk at point."
639 (interactive)
640 (let* ((hunk-bounds (diff-bounds-of-hunk))
641 (file-bounds (ignore-errors (diff-bounds-of-file)))
642 ;; If the current hunk is the only one for its file, kill the
643 ;; file header too.
644 (bounds (if (and file-bounds
645 (progn (goto-char (car file-bounds))
646 (= (progn (diff-hunk-next) (point))
647 (car hunk-bounds)))
648 (progn (goto-char (cadr hunk-bounds))
649 ;; bzr puts a newline after the last hunk.
651 (forward-char 1))
652 (= (point) (cadr file-bounds))))
653 file-bounds
654 hunk-bounds))
655 (inhibit-read-only t))
656 (apply 'kill-region bounds)
657 (goto-char (car bounds))))
659 ;; "index ", "old mode", "new mode", "new file mode" and
660 ;; "deleted file mode" are output by git-diff.
661 (defconst diff-file-junk-re
664 (defun diff-beginning-of-file-and-junk ()
665 "Go to the beginning of file-related diff-info.
666 This is like `diff-beginning-of-file' except it tries to skip back over leading
668 (let* ((orig (point))
669 ;; Skip forward over what might be "leading junk" so as to get
670 ;; closer to the actual diff.
671 (_ (progn (beginning-of-line)
672 (while (looking-at diff-file-junk-re)
673 (forward-line 1))))
674 (start (point))
675 (prevfile (condition-case err
676 (save-excursion (diff-beginning-of-file) (point))
677 (error err)))
678 (err (if (consp prevfile) prevfile))
679 (nextfile (ignore-errors
680 (save-excursion
681 (goto-char start) (diff-file-next) (point))))
682 ;; prevhunk is one of the limits.
683 (prevhunk (save-excursion
684 (ignore-errors
685 (if (numberp prevfile) (goto-char prevfile))
686 (diff-hunk-prev) (point))))
687 (previndex (save-excursion
688 (forward-line 1) ;In case we're looking at "Index:".
689 (re-search-backward "^Index: " prevhunk t))))
690 ;; If we're in the junk, we should use nextfile instead of prevfile.
691 (if (and (numberp nextfile)
692 (or (not (numberp prevfile))
693 (and previndex (> previndex prevfile))))
694 (setq prevfile nextfile))
695 (if (and previndex (numberp prevfile) (< previndex prevfile))
696 (setq prevfile previndex))
697 (if (and (numberp prevfile) (<= prevfile start))
698 (progn
699 (goto-char prevfile)
700 ;; Now skip backward over the leading junk we may have before the
701 ;; diff itself.
702 (while (save-excursion
703 (and (zerop (forward-line -1))
704 (looking-at diff-file-junk-re)))
705 (forward-line -1)))
706 ;; File starts *after* the starting point: we really weren't in
707 ;; a file diff but elsewhere.
708 (goto-char orig)
709 (signal (car err) (cdr err)))))
711 (defun diff-file-kill ()
712 "Kill current file's hunks."
713 (interactive)
714 (let ((inhibit-read-only t))
715 (apply 'kill-region (diff-bounds-of-file))))
717 (defun diff-kill-junk ()
718 "Kill spurious empty diffs."
719 (interactive)
720 (save-excursion
721 (let ((inhibit-read-only t))
722 (goto-char (point-min))
727 nil t)
728 (delete-region (if (match-end 4) (match-beginning 0) (match-end 1))
729 (match-beginning 3))
730 (beginning-of-line)))))
732 (defun diff-count-matches (re start end)
733 (save-excursion
734 (let ((n 0))
735 (goto-char start)
736 (while (re-search-forward re end t) (cl-incf n))
737 n)))
739 (defun diff-splittable-p ()
740 (save-excursion
741 (beginning-of-line)
742 (and (looking-at "^[-+ ]")
743 (progn (forward-line -1) (looking-at "^[-+ ]"))
744 (diff-unified-hunk-p))))
746 (defun diff-split-hunk ()
747 "Split the current (unified diff) hunk at point into two hunks."
748 (interactive)
749 (beginning-of-line)
750 (let ((pos (point))
751 (start (diff-beginning-of-hunk)))
752 (unless (looking-at diff-hunk-header-re-unified)
753 (error "diff-split-hunk only works on unified context diffs"))
754 (forward-line 1)
755 (let* ((start1 (string-to-number (match-string 1)))
756 (start2 (string-to-number (match-string 3)))
759 (inhibit-read-only t))
760 (goto-char pos)
761 ;; Hopefully the after-change-function will not screw us over.
762 (insert "@@ -" (number-to-string newstart1) ",1 +"
764 ;; Fix the original hunk-header.
765 (diff-fixup-modifs start pos))))
768 ;;;;
769 ;;;; jump to other buffers
770 ;;;;
772 (defvar diff-remembered-files-alist nil)
773 (defvar diff-remembered-defdir nil)
775 (defun diff-filename-drop-dir (file)
776 (when (string-match "/" file) (substring file (match-end 0))))
778 (defun diff-merge-strings (ancestor from to)
779 "Merge the diff between ANCESTOR and FROM into TO.
780 Returns the merged string if successful or nil otherwise.
782 If ANCESTOR = FROM, returns TO.
783 If ANCESTOR = TO, returns FROM.
784 The heuristic is simplistic and only really works for cases
786 ;; Ideally, we want:
787 ;; AMB ANB CMD -> CND
788 ;; but that's ambiguous if `foo' or `bar' is empty:
789 ;; a/foo a/foo1 b/foo.c -> b/foo1.c but not 1b/foo.c or b/foo.c1
791 (when (and (string-match (concat
795 (equal to (match-string 5 str)))
796 (concat (substring str (match-beginning 5) (match-beginning 6))
797 (match-string 4 str)
798 (substring str (match-end 6) (match-end 5))))))
800 (defun diff-tell-file-name (old name)
801 "Tell Emacs where the find the source file of the current hunk.
802 If the OLD prefix arg is passed, tell the file NAME of the old file."
803 (interactive
804 (let* ((old current-prefix-arg)
805 (fs (diff-hunk-file-names current-prefix-arg)))
806 (unless fs (error "No file name to look for"))
807 (list old (read-file-name (format "File for %s: " (car fs))
808 nil (diff-find-file-name old 'noprompt) t))))
809 (let ((fs (diff-hunk-file-names old)))
810 (unless fs (error "No file name to look for"))
811 (push (cons fs name) diff-remembered-files-alist)))
813 (defun diff-hunk-file-names (&optional old)
814 "Give the list of file names textually mentioned for the current hunk."
815 (save-excursion
816 (unless (looking-at diff-file-header-re)
817 (or (ignore-errors (diff-beginning-of-file))
818 (re-search-forward diff-file-header-re nil t)))
819 (let ((limit (save-excursion
820 (condition-case ()
821 (progn (diff-hunk-prev) (point))
822 (error (point-min)))))
823 (header-files
825 (list (if old (match-string 1) (match-string 3))
826 (if old (match-string 3) (match-string 1)))
827 (forward-line 1) nil)))
828 (delq nil
829 (append
830 (when (and (not old)
831 (save-excursion
833 (list (match-string 1)))
834 header-files
835 (when (re-search-backward
837 nil t)
838 (list (if old (match-string 2) (match-string 4))
839 (if old (match-string 4) (match-string 2)))))))))
841 (defun diff-find-file-name (&optional old noprompt prefix)
842 "Return the file corresponding to the current patch.
843 Non-nil OLD means that we want the old file.
844 Non-nil NOPROMPT means to prefer returning nil than to prompt the user.
845 PREFIX is only used internally: don't use it."
846 (unless (equal diff-remembered-defdir default-directory)
847 ;; Flush diff-remembered-files-alist if the default-directory is changed.
848 (set (make-local-variable 'diff-remembered-defdir) default-directory)
849 (set (make-local-variable 'diff-remembered-files-alist) nil))
850 (save-excursion
851 (unless (looking-at diff-file-header-re)
852 (or (ignore-errors (diff-beginning-of-file))
853 (re-search-forward diff-file-header-re nil t)))
854 (let ((fs (diff-hunk-file-names old)))
855 (if prefix (setq fs (mapcar (lambda (f) (concat prefix f)) fs)))
856 (or
857 ;; use any previously used preference
858 (cdr (assoc fs diff-remembered-files-alist))
859 ;; try to be clever and use previous choices as an inspiration
860 (cl-dolist (rf diff-remembered-files-alist)
861 (let ((newfile (diff-merge-strings (caar rf) (car fs) (cdr rf))))
862 (if (and newfile (file-exists-p newfile)) (cl-return newfile))))
863 ;; look for each file in turn. If none found, try again but
864 ;; ignoring the first level of directory, ...
865 (cl-do* ((files fs (delq nil (mapcar 'diff-filename-drop-dir files)))
866 (file nil nil))
867 ((or (null files)
868 (setq file (cl-do* ((files files (cdr files))
869 (file (car files) (car files)))
870 ;; Use file-regular-p to avoid
871 ;; /dev/null, directories, etc.
872 ((or (null file) (file-regular-p file))
873 file))))
874 file))
875 ;; <foo>.rej patches implicitly apply to <foo>
877 (let ((file (substring buffer-file-name 0 (match-beginning 0))))
878 (when (file-exists-p file) file)))
879 ;; If we haven't found the file, maybe it's because we haven't paid
880 ;; attention to the PCL-CVS hint.
881 (and (not prefix)
882 (boundp 'cvs-pcl-cvs-dirchange-re)
883 (save-excursion
884 (re-search-backward cvs-pcl-cvs-dirchange-re nil t))
885 (diff-find-file-name old noprompt (match-string 1)))
886 ;; if all else fails, ask the user
887 (unless noprompt
888 (let ((file (expand-file-name (or (car fs) ""))))
889 (setq file
890 (read-file-name (format "Use file %s: " file)
891 (file-name-directory file) file t
892 (file-name-nondirectory file)))
893 (set (make-local-variable 'diff-remembered-files-alist)
894 (cons (cons fs file) diff-remembered-files-alist))
895 file))))))
898 (defun diff-ediff-patch ()
899 "Call `ediff-patch-file' on the current buffer."
900 (interactive)
901 (condition-case nil
902 (ediff-patch-file nil (current-buffer))
903 (wrong-number-of-arguments (ediff-patch-file))))
905 ;;;;
906 ;;;; Conversion functions
907 ;;;;
909 ;;(defvar diff-inhibit-after-change nil
910 ;; "Non-nil means inhibit `diff-mode's after-change functions.")
912 (defun diff-unified->context (start end)
913 "Convert unified diffs to context diffs.
914 START and END are either taken from the region (if a prefix arg is given) or
915 else cover the whole buffer."
916 (interactive (if (or current-prefix-arg (use-region-p))
917 (list (region-beginning) (region-end))
918 (list (point-min) (point-max))))
919 (unless (markerp end) (setq end (copy-marker end t)))
920 (let (;;(diff-inhibit-after-change t)
921 (inhibit-read-only t))
922 (save-excursion
923 (goto-char start)
924 (while (and (re-search-forward
927 nil t)
928 (< (point) end))
929 (combine-after-change-calls
930 (if (match-beginning 2)
931 ;; we matched a file header
932 (progn
933 ;; use reverse order to make sure the indices are kept valid
934 (replace-match "---" t t nil 3)
935 (replace-match "***" t t nil 2))
936 ;; we matched a hunk header
937 (let ((line1 (match-string 4))
938 (lines1 (or (match-string 5) "1"))
939 (line2 (match-string 6))
940 (lines2 (or (match-string 7) "1"))
941 ;; Variables to use the special undo function.
942 (old-undo buffer-undo-list)
943 (old-end (marker-position end))
944 (start (match-beginning 0))
945 (reversible t))
946 (replace-match
948 (number-to-string (+ (string-to-number line1)
949 (string-to-number lines1)
950 -1))
951 " ****"))
952 (save-restriction
953 (narrow-to-region (line-beginning-position 2)
954 ;; Call diff-end-of-hunk from just before
955 ;; the hunk header so it can use the hunk
956 ;; header info.
957 (progn (diff-end-of-hunk 'unified) (point)))
958 (let ((hunk (buffer-string)))
959 (goto-char (point-min))
960 (if (not (save-excursion (re-search-forward "^-" nil t)))
961 (delete-region (point) (point-max))
962 (goto-char (point-max))
963 (let ((modif nil) last-pt)
964 (while (progn (setq last-pt (point))
965 (= (forward-line -1) 0))
966 (pcase (char-after)
967 (?\s (insert " ") (setq modif nil) (backward-char 1))
968 (?+ (delete-region (point) last-pt) (setq modif t))
969 (?- (if (not modif)
970 (progn (forward-char 1)
971 (insert " "))
972 (delete-char 1)
973 (insert "! "))
974 (backward-char 2))
976 (= (char-after) ?+))
977 (delete-region (point) last-pt)
978 (setq modif t)))
979 ;; diff-valid-unified-empty-line.
981 (backward-char 2))
982 (_ (setq modif nil))))))
983 (goto-char (point-max))
984 (save-excursion
985 (insert "--- " line2 ","
986 (number-to-string (+ (string-to-number line2)
987 (string-to-number lines2)
988 -1))
990 ;;(goto-char (point-min))
991 (forward-line 1)
992 (if (not (save-excursion (re-search-forward "^+" nil t)))
993 (delete-region (point) (point-max))
994 (let ((modif nil) (delete nil))
996 nil t))
997 ;; Normally, lines in a substitution come with
998 ;; first the removals and then the additions, and
999 ;; the context->unified function follows this
1000 ;; convention, of course. Yet, other alternatives
1001 ;; are valid as well, but they preclude the use of
1002 ;; context->unified as an undo command.
1003 (setq reversible nil))
1004 (while (not (eobp))
1005 (pcase (char-after)
1006 (?\s (insert " ") (setq modif nil) (backward-char 1))
1007 (?- (setq delete t) (setq modif t))
1008 (?+ (if (not modif)
1009 (progn (forward-char 1)
1010 (insert " "))
1011 (delete-char 1)
1012 (insert "! "))
1013 (backward-char 2))
1015 (not (eobp)))
1016 (setq delete t) (setq modif t)))
1017 ;; diff-valid-unified-empty-line.
1019 (setq reversible nil))
1020 (_ (setq modif nil)))
1021 (let ((last-pt (point)))
1022 (forward-line 1)
1023 (when delete
1024 (delete-region last-pt (point))
1025 (setq delete nil)))))))
1026 (unless (or (not reversible) (eq buffer-undo-list t))
1027 ;; Drop the many undo entries and replace them with
1028 ;; a single entry that uses diff-context->unified to do
1029 ;; the work.
1030 (setq buffer-undo-list
1031 (cons (list 'apply (- old-end end) start (point-max)
1032 'diff-context->unified start (point-max))
1033 old-undo)))))))))))
1035 (defun diff-context->unified (start end &optional to-context)
1036 "Convert context diffs to unified diffs.
1037 START and END are either taken from the region
1038 \(when it is highlighted) or else cover the whole buffer.
1039 With a prefix argument, convert unified format to context format."
1040 (interactive (if (use-region-p)
1041 (list (region-beginning) (region-end) current-prefix-arg)
1042 (list (point-min) (point-max) current-prefix-arg)))
1043 (if to-context
1044 (diff-unified->context start end)
1045 (unless (markerp end) (setq end (copy-marker end t)))
1046 (let ( ;;(diff-inhibit-after-change t)
1047 (inhibit-read-only t))
1048 (save-excursion
1049 (goto-char start)
1050 (while (and (re-search-forward "^\\(\\(\\*\\*\\*\\) .+\n\\(---\\) .+\\|\\*\\{15\\}.*\n\\*\\*\\* \\([0-9]+\\),\\(-?[0-9]+\\) \\*\\*\\*\\*\\)\\(?: \\(.*\\)\\|$\\)" nil t)
1051 (< (point) end))
1052 (combine-after-change-calls
1053 (if (match-beginning 2)
1054 ;; we matched a file header
1055 (progn
1056 ;; use reverse order to make sure the indices are kept valid
1057 (replace-match "+++" t t nil 3)
1058 (replace-match "---" t t nil 2))
1059 ;; we matched a hunk header
1060 (let ((line1s (match-string 4))
1061 (line1e (match-string 5))
1062 (pt1 (match-beginning 0))
1063 ;; Variables to use the special undo function.
1064 (old-undo buffer-undo-list)
1065 (old-end (marker-position end))
1066 ;; We currently throw away the comment that can follow
1067 ;; the hunk header. FIXME: Preserve it instead!
1068 (reversible (not (match-end 6))))
1069 (replace-match "")
1070 (unless (re-search-forward
1071 diff-context-mid-hunk-header-re nil t)
1072 (error "Can't find matching `--- n1,n2 ----' line"))
1073 (let ((line2s (match-string 1))
1074 (line2e (match-string 2))
1075 (pt2 (progn
1076 (delete-region (progn (beginning-of-line) (point))
1077 (progn (forward-line 1) (point)))
1078 (point-marker))))
1079 (goto-char pt1)
1080 (forward-line 1)
1081 (while (< (point) pt2)
1082 (pcase (char-after)
1083 (?! (delete-char 2) (insert "-") (forward-line 1))
1084 (?- (forward-char 1) (delete-char 1) (forward-line 1))
1085 (?\s ;merge with the other half of the chunk
1086 (let* ((endline2
1087 (save-excursion
1088 (goto-char pt2) (forward-line 1) (point))))
1089 (pcase (char-after pt2)
1090 ((or ?! ?+)
1091 (insert "+"
1092 (prog1
1093 (buffer-substring (+ pt2 2) endline2)
1094 (delete-region pt2 endline2))))
1095 (?\s
1096 (unless (= (- endline2 pt2)
1097 (- (line-beginning-position 2) (point)))
1098 ;; If the two lines we're merging don't have the
1099 ;; same length (can happen with "diff -b"), then
1100 ;; diff-unified->context will not properly undo
1101 ;; this operation.
1102 (setq reversible nil))
1103 (delete-region pt2 endline2)
1104 (delete-char 1)
1105 (forward-line 1))
1107 (_ (setq reversible nil)
1108 (delete-char 1) (forward-line 1)))))
1109 (_ (setq reversible nil) (forward-line 1))))
1110 (while (looking-at "[+! ] ")
1111 (if (/= (char-after) ?!) (forward-char 1)
1112 (delete-char 1) (insert "+"))
1113 (delete-char 1) (forward-line 1))
1114 (save-excursion
1115 (goto-char pt1)
1116 (insert "@@ -" line1s ","
1117 (number-to-string (- (string-to-number line1e)
1118 (string-to-number line1s)
1119 -1))
1120 " +" line2s ","
1121 (number-to-string (- (string-to-number line2e)
1122 (string-to-number line2s)
1123 -1)) " @@"))
1124 (set-marker pt2 nil)
1125 ;; The whole procedure succeeded, let's replace the myriad
1126 ;; of undo elements with just a single special one.
1127 (unless (or (not reversible) (eq buffer-undo-list t))
1128 (setq buffer-undo-list
1129 (cons (list 'apply (- old-end end) pt1 (point)
1130 'diff-unified->context pt1 (point))
1131 old-undo)))
1132 )))))))))
1134 (defun diff-reverse-direction (start end)
1135 "Reverse the direction of the diffs.
1136 START and END are either taken from the region (if a prefix arg is given) or
1137 else cover the whole buffer."
1138 (interactive (if (or current-prefix-arg (use-region-p))
1139 (list (region-beginning) (region-end))
1140 (list (point-min) (point-max))))
1141 (unless (markerp end) (setq end (copy-marker end t)))
1142 (let (;;(diff-inhibit-after-change t)
1143 (inhibit-read-only t))
1144 (save-excursion
1145 (goto-char start)
1146 (while (and (re-search-forward "^\\(\\([-*][-*][-*] \\)\\(.+\\)\n\\([-+][-+][-+] \\)\\(.+\\)\\|\\*\\{15\\}.*\n\\*\\*\\* \\(.+\\) \\*\\*\\*\\*\\|@@ -\\([0-9,]+\\) \\+\\([0-9,]+\\) @@.*\\)$" nil t)
1147 (< (point) end))
1148 (combine-after-change-calls
1149 (cond
1150 ;; a file header
1152 ;; a context-diff hunk header
1153 ((match-beginning 6)
1154 (let ((pt-lines1 (match-beginning 6))
1155 (lines1 (match-string 6)))
1156 (replace-match "" nil nil nil 6)
1157 (forward-line 1)
1158 (let ((half1s (point)))
1160 (when (= (char-after) ?-) (delete-char 1) (insert "+"))
1161 (forward-line 1))
1162 (let ((half1 (delete-and-extract-region half1s (point))))
1163 (unless (looking-at diff-context-mid-hunk-header-re)
1164 (insert half1)
1165 (error "Can't find matching `--- n1,n2 ----' line"))
1166 (let* ((str1end (or (match-end 2) (match-end 1)))
1167 (str1 (buffer-substring (match-beginning 1) str1end)))
1168 (goto-char str1end)
1169 (insert lines1)
1170 (delete-region (match-beginning 1) str1end)
1171 (forward-line 1)
1172 (let ((half2s (point)))
1174 (when (= (char-after) ?+) (delete-char 1) (insert "-"))
1175 (forward-line 1))
1176 (let ((half2 (delete-and-extract-region half2s (point))))
1177 (insert (or half1 ""))
1178 (goto-char half1s)
1179 (insert (or half2 ""))))
1180 (goto-char pt-lines1)
1181 (insert str1))))))
1182 ;; a unified-diff hunk header
1183 ((match-beginning 7)
1185 (forward-line 1)
1186 (let ((c (char-after)) first last)
1187 (while (pcase (setq c (char-after))
1188 (?- (setq first (or first (point)))
1189 (delete-char 1) (insert "+") t)
1190 (?+ (setq last (or last (point)))
1191 (delete-char 1) (insert "-") t)
1193 (_ (when (and first last (< first last))
1194 (insert (delete-and-extract-region first last)))
1195 (setq first nil last nil)
1196 (memq c (if diff-valid-unified-empty-line
1198 (forward-line 1))))))))))
1200 (defun diff-fixup-modifs (start end)
1201 "Fixup the hunk headers (in case the buffer was modified).
1202 START and END are either taken from the region (if a prefix arg is given) or
1203 else cover the whole buffer."
1204 (interactive (if (or current-prefix-arg (use-region-p))
1205 (list (region-beginning) (region-end))
1206 (list (point-min) (point-max))))
1207 (let ((inhibit-read-only t))
1208 (save-excursion
1209 (goto-char end) (diff-end-of-hunk nil 'donttrustheader)
1210 (let ((plus 0) (minus 0) (space 0) (bang 0))
1211 (while (and (= (forward-line -1) 0) (<= start (point)))
1212 (if (not (looking-at
1213 (concat diff-hunk-header-re-unified
1216 (pcase (char-after)
1217 (?\s (cl-incf space))
1218 (?+ (cl-incf plus))
1219 (?- (cl-incf minus))
1220 (?! (cl-incf bang))
1222 (_ (setq space 0 plus 0 minus 0 bang 0)))
1223 (cond
1224 ((looking-at diff-hunk-header-re-unified)
1225 (let* ((old1 (match-string 2))
1226 (old2 (match-string 4))
1227 (new1 (number-to-string (+ space minus)))
1228 (new2 (number-to-string (+ space plus))))
1229 (if old2
1230 (unless (string= new2 old2) (replace-match new2 t t nil 4))
1231 (goto-char (match-end 3))
1232 (insert "," new2))
1233 (if old1
1234 (unless (string= new1 old1) (replace-match new1 t t nil 2))
1235 (goto-char (match-end 1))
1236 (insert "," new1))))
1237 ((looking-at diff-context-mid-hunk-header-re)
1238 (when (> (+ space bang plus) 0)
1239 (let* ((old1 (match-string 1))
1240 (old2 (match-string 2))
1241 (new (number-to-string
1242 (+ space bang plus -1 (string-to-number old1)))))
1243 (unless (string= new old2) (replace-match new t t nil 2)))))
1245 (when (> (+ space bang minus) 0)
1246 (let* ((old (match-string 1))
1247 (new (format
1248 (concat "%0" (number-to-string (length old)) "d")
1249 (+ space bang minus -1 (string-to-number old)))))
1250 (unless (string= new old) (replace-match new t t nil 2))))))
1251 (setq space 0 plus 0 minus 0 bang 0)))))))
1253 ;;;;
1254 ;;;; Hooks
1255 ;;;;
1257 (defun diff-write-contents-hooks ()
1258 "Fixup hunk headers if necessary."
1259 (if (buffer-modified-p) (diff-fixup-modifs (point-min) (point-max)))
1260 nil)
1262 ;; It turns out that making changes in the buffer from within an
1263 ;; *-change-function is asking for trouble, whereas making them
1264 ;; from a post-command-hook doesn't pose much problems
1265 (defvar diff-unhandled-changes nil)
1266 (defun diff-after-change-function (beg end _len)
1267 "Remember to fixup the hunk header.
1268 See `after-change-functions' for the meaning of BEG, END and LEN."
1269 ;; Ignoring changes when inhibit-read-only is set is strictly speaking
1270 ;; incorrect, but it turns out that inhibit-read-only is normally not set
1271 ;; inside editing commands, while it tends to be set when the buffer gets
1272 ;; updated by an async process or by a conversion function, both of which
1273 ;; would rather not be uselessly slowed down by this hook.
1274 (when (and (not undo-in-progress) (not inhibit-read-only))
1275 (if diff-unhandled-changes
1276 (setq diff-unhandled-changes
1277 (cons (min beg (car diff-unhandled-changes))
1278 (max end (cdr diff-unhandled-changes))))
1279 (setq diff-unhandled-changes (cons beg end)))))
1281 (defun diff-post-command-hook ()
1282 "Fixup hunk headers if necessary."
1283 (when (consp diff-unhandled-changes)
1284 (ignore-errors
1285 (save-excursion
1286 (goto-char (car diff-unhandled-changes))
1287 ;; Maybe we've cut the end of the hunk before point.
1288 (if (and (bolp) (not (bobp))) (backward-char 1))
1289 ;; We used to fixup modifs on all the changes, but it turns out that
1290 ;; it's safer not to do it on big changes, e.g. when yanking a big
1291 ;; diff, or when the user edits the header, since we might then
1292 ;; screw up perfectly correct values. --Stef
1293 (diff-beginning-of-hunk)
1295 (start (line-beginning-position (if (eq style 'context) 3 2)))
1296 (mid (if (eq style 'context)
1297 (save-excursion
1298 (re-search-forward diff-context-mid-hunk-header-re
1299 nil t)))))
1300 (when (and ;; Don't try to fixup changes in the hunk header.
1301 (>= (car diff-unhandled-changes) start)
1302 ;; Don't try to fixup changes in the mid-hunk header either.
1303 (or (not mid)
1304 (< (cdr diff-unhandled-changes) (match-beginning 0))
1305 (> (car diff-unhandled-changes) (match-end 0)))
1306 (save-excursion
1307 (diff-end-of-hunk nil 'donttrustheader)
1308 ;; Don't try to fixup changes past the end of the hunk.
1309 (>= (point) (cdr diff-unhandled-changes))))
1310 (diff-fixup-modifs (point) (cdr diff-unhandled-changes)))))
1311 (setq diff-unhandled-changes nil))))
1313 (defun diff-next-error (arg reset)
1314 ;; Select a window that displays the current buffer so that point
1315 ;; movements are reflected in that window. Otherwise, the user might
1316 ;; never see the hunk corresponding to the source she's jumping to.
1317 (pop-to-buffer (current-buffer))
1318 (if reset (goto-char (point-min)))
1319 (diff-hunk-next arg)
1320 (diff-goto-source))
1322 (defvar whitespace-style)
1323 (defvar whitespace-trailing-regexp)
1325 ;;;###autoload
1326 (define-derived-mode diff-mode fundamental-mode "Diff"
1327 "Major mode for viewing/editing context diffs.
1328 Supports unified and context diffs as well as (to a lesser extent)
1329 normal diffs.
1331 When the buffer is read-only, the ESC prefix is not necessary.
1332 If you edit the buffer manually, diff-mode will try to update the hunk
1333 headers for you on-the-fly.
1341 (set (make-local-variable 'font-lock-defaults) diff-font-lock-defaults)
1342 (add-hook 'font-lock-mode-hook
1343 (lambda () (remove-overlays nil nil 'diff-mode 'fine))
1344 nil 'local)
1345 (set (make-local-variable 'outline-regexp) diff-outline-regexp)
1346 (set (make-local-variable 'imenu-generic-expression)
1347 diff-imenu-generic-expression)
1348 ;; These are not perfect. They would be better done separately for
1349 ;; context diffs and unidiffs.
1350 ;; (set (make-local-variable 'paragraph-start)
1351 ;; (concat "@@ " ; unidiff hunk
1354 ;; ; start (first or second line)
1355 ;; (set (make-local-variable 'paragraph-separate) paragraph-start)
1357 ;; compile support
1358 (set (make-local-variable 'next-error-function) 'diff-next-error)
1360 (set (make-local-variable 'beginning-of-defun-function)
1361 'diff-beginning-of-file-and-junk)
1362 (set (make-local-variable 'end-of-defun-function)
1363 'diff-end-of-file)
1365 (diff-setup-whitespace)
1367 (setq buffer-read-only diff-default-read-only)
1368 ;; setup change hooks
1369 (if (not diff-update-on-the-fly)
1370 (add-hook 'write-contents-functions 'diff-write-contents-hooks nil t)
1371 (make-local-variable 'diff-unhandled-changes)
1372 (add-hook 'after-change-functions 'diff-after-change-function nil t)
1373 (add-hook 'post-command-hook 'diff-post-command-hook nil t))
1374 ;; Neat trick from Dave Love to add more bindings in read-only mode:
1375 (let ((ro-bind (cons 'buffer-read-only diff-mode-shared-map)))
1376 (add-to-list 'minor-mode-overriding-map-alist ro-bind)
1377 ;; Turn off this little trick in case the buffer is put in view-mode.
1378 (add-hook 'view-mode-hook
1379 (lambda ()
1380 (setq minor-mode-overriding-map-alist
1381 (delq ro-bind minor-mode-overriding-map-alist)))
1382 nil t))
1383 ;; add-log support
1384 (set (make-local-variable 'add-log-current-defun-function)
1385 'diff-current-defun)
1386 (set (make-local-variable 'add-log-buffer-file-name-function)
1387 (lambda () (diff-find-file-name nil 'noprompt)))
1388 (unless (buffer-file-name)
1389 (hack-dir-local-variables-non-file-buffer)))
1391 ;;;###autoload
1392 (define-minor-mode diff-minor-mode
1393 "Toggle Diff minor mode.
1394 With a prefix argument ARG, enable Diff minor mode if ARG is
1395 positive, and disable it otherwise. If called from Lisp, enable
1396 the mode if ARG is omitted or nil.
1399 :group 'diff-mode :lighter " Diff"
1400 ;; FIXME: setup font-lock
1401 ;; setup change hooks
1402 (if (not diff-update-on-the-fly)
1403 (add-hook 'write-contents-functions 'diff-write-contents-hooks nil t)
1404 (make-local-variable 'diff-unhandled-changes)
1405 (add-hook 'after-change-functions 'diff-after-change-function nil t)
1406 (add-hook 'post-command-hook 'diff-post-command-hook nil t)))
1408 ;;; Handy hook functions ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
1410 (defun diff-setup-whitespace ()
1411 "Set up Whitespace mode variables for the current Diff mode buffer.
1412 This sets `whitespace-style' and `whitespace-trailing-regexp' so
1413 that Whitespace mode shows trailing whitespace problems on the
1414 modified lines of the diff."
1415 (set (make-local-variable 'whitespace-style) '(face trailing))
1416 (let ((style (save-excursion
1417 (goto-char (point-min))
1418 ;; FIXME: For buffers filled from async processes, this search
1419 ;; will simply fail because the buffer is still empty :-(
1420 (when (re-search-forward diff-hunk-header-re nil t)
1421 (goto-char (match-beginning 0))
1422 (diff-hunk-style)))))
1423 (set (make-local-variable 'whitespace-trailing-regexp)
1424 (if (eq style 'context)
1428 (defun diff-delete-if-empty ()
1429 ;; An empty diff file means there's no more diffs to integrate, so we
1430 ;; can just remove the file altogether. Very handy for .rej files if we
1431 ;; remove hunks as we apply them.
1432 (when (and buffer-file-name
1433 (eq 0 (nth 7 (file-attributes buffer-file-name))))
1434 (delete-file buffer-file-name)))
1436 (defun diff-delete-empty-files ()
1437 "Arrange for empty diff files to be removed."
1438 (add-hook 'after-save-hook 'diff-delete-if-empty nil t))
1440 (defun diff-make-unified ()
1441 "Turn context diffs into unified diffs if applicable."
1442 (if (save-excursion
1443 (goto-char (point-min))
1444 (and (looking-at diff-hunk-header-re) (eq (char-after) ?*)))
1445 (let ((mod (buffer-modified-p)))
1446 (unwind-protect
1447 (diff-context->unified (point-min) (point-max))
1448 (restore-buffer-modified-p mod)))))
1450 ;;;
1451 ;;; Misc operations that have proved useful at some point.
1452 ;;;
1454 (defun diff-next-complex-hunk ()
1457 Only works for unified diffs."
1458 (interactive)
1459 (while
1460 (and (re-search-forward diff-hunk-header-re-unified nil t)
1461 (equal (match-string 2) (match-string 4)))))
1463 (defun diff-sanity-check-context-hunk-half (lines)
1464 (let ((count lines))
1465 (while
1466 (cond
1467 ((and (memq (char-after) '(?\s ?! ?+ ?-))
1469 (cl-decf count) t)
1470 ((or (zerop count) (= count lines)) nil)
1471 ((memq (char-after) '(?! ?+ ?-))
1473 (y-or-n-p "Try to auto-fix whitespace loss damage? ")))
1474 (error "End of hunk ambiguously marked")
1475 (forward-char 1) (insert " ") (forward-line -1) t))
1476 ((< lines 0)
1477 (error "End of hunk ambiguously marked"))
1478 ((not (y-or-n-p "Try to auto-fix whitespace loss and word-wrap damage? "))
1479 (error "Abort!"))
1480 ((eolp) (insert " ") (forward-line -1) t)
1481 (t (insert " ") (delete-region (- (point) 2) (- (point) 1)) t))
1482 (forward-line))))
1484 (defun diff-sanity-check-hunk ()
1485 (let (;; Every modification is protected by a y-or-n-p, so it's probably
1486 ;; OK to override a read-only setting.
1487 (inhibit-read-only t))
1488 (save-excursion
1489 (cond
1490 ((not (looking-at diff-hunk-header-re))
1491 (error "Not recognizable hunk header"))
1493 ;; A context diff.
1494 ((eq (char-after) ?*)
1495 (if (not (looking-at "\\*\\{15\\}\\(?: .*\\)?\n\\*\\*\\* \\([0-9]+\\)\\(?:,\\([0-9]+\\)\\)? \\*\\*\\*\\*"))
1496 (error "Unrecognized context diff first hunk header format")
1497 (forward-line 2)
1498 (diff-sanity-check-context-hunk-half
1499 (if (match-end 2)
1500 (1+ (- (string-to-number (match-string 2))
1501 (string-to-number (match-string 1))))
1502 1))
1503 (if (not (looking-at diff-context-mid-hunk-header-re))
1504 (error "Unrecognized context diff second hunk header format")
1505 (forward-line)
1506 (diff-sanity-check-context-hunk-half
1507 (if (match-end 2)
1508 (1+ (- (string-to-number (match-string 2))
1509 (string-to-number (match-string 1))))
1510 1)))))
1512 ;; A unified diff.
1513 ((eq (char-after) ?@)
1514 (if (not (looking-at diff-hunk-header-re-unified))
1515 (error "Unrecognized unified diff hunk header format")
1516 (let ((before (string-to-number (or (match-string 2) "1")))
1517 (after (string-to-number (or (match-string 4) "1"))))
1518 (forward-line)
1519 (while
1520 (pcase (char-after)
1521 (?\s (cl-decf before) (cl-decf after) t)
1522 (?-
1523 (if (and (looking-at diff-file-header-re)
1524 (zerop before) (zerop after))
1525 ;; No need to query: this is a case where two patches
1526 ;; are concatenated and only counting the lines will
1527 ;; give the right result. Let's just add an empty
1528 ;; line so that our code which doesn't count lines
1529 ;; will not get confused.
1531 (cl-decf before) t))
1532 (?+ (cl-decf after) t)
1533 (_
1534 (cond
1535 ((and diff-valid-unified-empty-line
1536 ;; Not just (eolp) so we don't infloop at eob.
1538 (> before 0) (> after 0))
1539 (cl-decf before) (cl-decf after) t)
1540 ((and (zerop before) (zerop after)) nil)
1541 ((or (< before 0) (< after 0))
1542 (error (if (or (zerop before) (zerop after))
1543 "End of hunk ambiguously marked"
1544 "Hunk seriously messed up")))
1545 ((not (y-or-n-p (concat "Try to auto-fix " (if (eolp) "whitespace loss" "word-wrap damage") "? ")))
1546 (error "Abort!"))
1547 ((eolp) (insert " ") (forward-line -1) t)
1548 (t (insert " ")
1549 (delete-region (- (point) 2) (- (point) 1)) t))))
1550 (forward-line)))))
1552 ;; A plain diff.
1553 (t
1554 ;; TODO.
1555 )))))
1557 (defun diff-hunk-text (hunk destp char-offset)
1558 "Return the literal source text from HUNK as (TEXT . OFFSET).
1559 If DESTP is nil, TEXT is the source, otherwise the destination text.
1560 CHAR-OFFSET is a char-offset in HUNK, and OFFSET is the corresponding
1561 char-offset in TEXT."
1562 (with-temp-buffer
1563 (insert hunk)
1564 (goto-char (point-min))
1565 (let ((src-pos nil)
1566 (dst-pos nil)
1567 (divider-pos nil)
1568 (num-pfx-chars 2))
1569 ;; Set the following variables:
1570 ;; SRC-POS buffer pos of the source part of the hunk or nil if none
1571 ;; DST-POS buffer pos of the destination part of the hunk or nil
1572 ;; DIVIDER-POS buffer pos of any divider line separating the src & dst
1573 ;; NUM-PFX-CHARS number of line-prefix characters used by this format"
1574 (cond ((looking-at "^@@")
1575 ;; unified diff
1576 (setq num-pfx-chars 1)
1577 (forward-line 1)
1578 (setq src-pos (point) dst-pos (point)))
1580 ;; context diff
1581 (forward-line 2)
1582 (setq src-pos (point))
1583 (re-search-forward diff-context-mid-hunk-header-re nil t)
1584 (forward-line 0)
1585 (setq divider-pos (point))
1586 (forward-line 1)
1587 (setq dst-pos (point)))
1588 ((looking-at "^[0-9]+a[0-9,]+$")
1589 ;; normal diff, insert
1590 (forward-line 1)
1591 (setq dst-pos (point)))
1592 ((looking-at "^[0-9,]+d[0-9]+$")
1593 ;; normal diff, delete
1594 (forward-line 1)
1595 (setq src-pos (point)))
1596 ((looking-at "^[0-9,]+c[0-9,]+$")
1597 ;; normal diff, change
1598 (forward-line 1)
1599 (setq src-pos (point))
1600 (re-search-forward "^---$" nil t)
1601 (forward-line 0)
1602 (setq divider-pos (point))
1603 (forward-line 1)
1604 (setq dst-pos (point)))
1605 (t
1606 (error "Unknown diff hunk type")))
1608 (if (if destp (null dst-pos) (null src-pos))
1609 ;; Implied empty text
1610 (if char-offset '("" . 0) "")
1612 ;; For context diffs, either side can be empty, (if there's only
1613 ;; added or only removed text). We should then use the other side.
1614 (cond ((equal src-pos divider-pos) (setq src-pos dst-pos))
1615 ((equal dst-pos (point-max)) (setq dst-pos src-pos)))
1617 (when char-offset (goto-char (+ (point-min) char-offset)))
1619 ;; Get rid of anything except the desired text.
1620 (save-excursion
1621 ;; Delete unused text region
1622 (let ((keep (if destp dst-pos src-pos)))
1623 (when (and divider-pos (> divider-pos keep))
1624 (delete-region divider-pos (point-max)))
1625 (delete-region (point-min) keep))
1626 ;; Remove line-prefix characters, and unneeded lines (unified diffs).
1627 (let ((kill-char (if destp ?- ?+)))
1628 (goto-char (point-min))
1629 (while (not (eobp))
1630 (if (eq (char-after) kill-char)
1631 (delete-region (point) (progn (forward-line 1) (point)))
1632 (delete-char num-pfx-chars)
1633 (forward-line 1)))))
1635 (let ((text (buffer-substring-no-properties (point-min) (point-max))))
1636 (if char-offset (cons text (- (point) (point-min))) text))))))
1639 (defun diff-find-text (text)
1640 "Return the buffer position (BEG . END) of the nearest occurrence of TEXT.
1641 If TEXT isn't found, nil is returned."
1642 (let* ((orig (point))
1643 (forw (and (search-forward text nil t)
1644 (cons (match-beginning 0) (match-end 0))))
1645 (back (and (goto-char (+ orig (length text)))
1646 (search-backward text nil t)
1647 (cons (match-beginning 0) (match-end 0)))))
1648 ;; Choose the closest match.
1649 (if (and forw back)
1650 (if (> (- (car forw) orig) (- orig (car back))) back forw)
1651 (or back forw))))
1653 (defun diff-find-approx-text (text)
1654 "Return the buffer position (BEG . END) of the nearest occurrence of TEXT.
1655 Whitespace differences are ignored."
1656 (let* ((orig (point))
1660 (forw (and (re-search-forward re nil t)
1661 (cons (match-beginning 0) (match-end 0))))
1662 (back (and (goto-char (+ orig (length text)))
1663 (re-search-backward re nil t)
1664 (cons (match-beginning 0) (match-end 0)))))
1665 ;; Choose the closest match.
1666 (if (and forw back)
1667 (if (> (- (car forw) orig) (- orig (car back))) back forw)
1668 (or back forw))))
1670 (defsubst diff-xor (a b) (if a (if (not b) a) b))
1672 (defun diff-find-source-location (&optional other-file reverse noprompt)
1673 "Find out (BUF LINE-OFFSET POS SRC DST SWITCHED).
1674 BUF is the buffer corresponding to the source file.
1675 LINE-OFFSET is the offset between the expected and actual positions
1676 of the text of the hunk or nil if the text was not found.
1677 POS is a pair (BEG . END) indicating the position of the text in the buffer.
1678 SRC and DST are the two variants of text as returned by `diff-hunk-text'.
1679 SRC is the variant that was found in the buffer.
1680 SWITCHED is non-nil if the patch is already applied.
1681 NOPROMPT, if non-nil, means not to prompt the user."
1682 (save-excursion
1683 (let* ((other (diff-xor other-file diff-jump-to-old-file))
1684 (char-offset (- (point) (diff-beginning-of-hunk t)))
1685 ;; Check that the hunk is well-formed. Otherwise diff-mode and
1686 ;; the user may disagree on what constitutes the hunk
1687 ;; (e.g. because an empty line truncates the hunk mid-course),
1688 ;; leading to potentially nasty surprises for the user.
1689 ;;
1690 ;; Suppress check when NOPROMPT is non-nil (Bug#3033).
1691 (_ (unless noprompt (diff-sanity-check-hunk)))
1692 (hunk (buffer-substring
1693 (point) (save-excursion (diff-end-of-hunk) (point))))
1694 (old (diff-hunk-text hunk reverse char-offset))
1695 (new (diff-hunk-text hunk (not reverse) char-offset))
1696 ;; Find the location specification.
1697 (line (if (not (looking-at "\\(?:\\*\\{15\\}.*\n\\)?[-@* ]*\\([0-9,]+\\)\\([ acd+]+\\([0-9,]+\\)\\)?"))
1698 (error "Can't find the hunk header")
1699 (if other (match-string 1)
1700 (if (match-end 3) (match-string 3)
1701 (unless (re-search-forward
1702 diff-context-mid-hunk-header-re nil t)
1703 (error "Can't find the hunk separator"))
1704 (match-string 1)))))
1705 (file (or (diff-find-file-name other noprompt)
1706 (error "Can't find the file")))
1707 (buf (find-file-noselect file)))
1708 ;; Update the user preference if he so wished.
1709 (when (> (prefix-numeric-value other-file) 8)
1710 (setq diff-jump-to-old-file other))
1711 (with-current-buffer buf
1712 (goto-char (point-min)) (forward-line (1- (string-to-number line)))
1713 (let* ((orig-pos (point))
1714 (switched nil)
1715 ;; FIXME: Check for case where both OLD and NEW are found.
1716 (pos (or (diff-find-text (car old))
1717 (progn (setq switched t) (diff-find-text (car new)))
1718 (progn (setq switched nil)
1719 (condition-case nil
1720 (diff-find-approx-text (car old))
1721 (invalid-regexp nil))) ;Regex too big.
1722 (progn (setq switched t)
1723 (condition-case nil
1724 (diff-find-approx-text (car new))
1725 (invalid-regexp nil))) ;Regex too big.
1726 (progn (setq switched nil) nil))))
1727 (nconc
1728 (list buf)
1729 (if pos
1730 (list (count-lines orig-pos (car pos)) pos)
1731 (list nil (cons orig-pos (+ orig-pos (length (car old))))))
1732 (if switched (list new old t) (list old new))))))))
1735 (defun diff-hunk-status-msg (line-offset reversed dry-run)
1736 (let ((msg (if dry-run
1737 (if reversed "already applied" "not yet applied")
1738 (if reversed "undone" "applied"))))
1739 (message (cond ((null line-offset) "Hunk text not found")
1740 ((= line-offset 0) "Hunk %s")
1741 ((= line-offset 1) "Hunk %s at offset %d line")
1742 (t "Hunk %s at offset %d lines"))
1743 msg line-offset)))
1745 (defvar diff-apply-hunk-to-backup-file nil)
1747 (defun diff-apply-hunk (&optional reverse)
1748 "Apply the current hunk to the source file and go to the next.
1749 By default, the new source file is patched, but if the variable
1750 `diff-jump-to-old-file' is non-nil, then the old source file is
1751 patched instead (some commands, such as `diff-goto-source' can change
1752 the value of this variable when given an appropriate prefix argument).
1754 With a prefix argument, REVERSE the hunk."
1755 (interactive "P")
1756 (pcase-let ((`(,buf ,line-offset ,pos ,old ,new ,switched)
1757 ;; Sometimes we'd like to have the following behavior: if
1758 ;; REVERSE go to the new file, otherwise go to the old.
1759 ;; But that means that by default we use the old file, which is
1760 ;; the opposite of the default for diff-goto-source, and is thus
1761 ;; confusing. Also when you don't know about it it's
1762 ;; pretty surprising.
1763 ;; TODO: make it possible to ask explicitly for this behavior.
1764 ;;
1765 ;; This is duplicated in diff-test-hunk.
1766 (diff-find-source-location nil reverse)))
1767 (cond
1768 ((null line-offset)
1769 (error "Can't find the text to patch"))
1770 ((with-current-buffer buf
1771 (and buffer-file-name
1772 (backup-file-name-p buffer-file-name)
1773 (not diff-apply-hunk-to-backup-file)
1774 (not (set (make-local-variable 'diff-apply-hunk-to-backup-file)
1775 (yes-or-no-p (format "Really apply this hunk to %s? "
1776 (file-name-nondirectory
1777 buffer-file-name)))))))
1778 (error "%s"
1779 (substitute-command-keys
1782 ((and switched
1783 ;; A reversed patch was detected, perhaps apply it in reverse.
1784 (not (save-window-excursion
1785 (pop-to-buffer buf)
1786 (goto-char (+ (car pos) (cdr old)))
1787 (y-or-n-p
1788 (if reverse
1789 "Hunk hasn't been applied yet; apply it now? "
1790 "Hunk has already been applied; undo it? ")))))
1791 (message "(Nothing done)"))
1792 (t
1793 ;; Apply the hunk
1794 (with-current-buffer buf
1795 (goto-char (car pos))
1796 (delete-region (car pos) (cdr pos))
1797 (insert (car new)))
1798 ;; Display BUF in a window
1799 (set-window-point (display-buffer buf) (+ (car pos) (cdr new)))
1800 (diff-hunk-status-msg line-offset (diff-xor switched reverse) nil)
1801 (when diff-advance-after-apply-hunk
1802 (diff-hunk-next))))))
1805 (defun diff-test-hunk (&optional reverse)
1806 "See whether it's possible to apply the current hunk.
1807 With a prefix argument, try to REVERSE the hunk."
1808 (interactive "P")
1809 (pcase-let ((`(,buf ,line-offset ,pos ,src ,_dst ,switched)
1810 (diff-find-source-location nil reverse)))
1811 (set-window-point (display-buffer buf) (+ (car pos) (cdr src)))
1812 (diff-hunk-status-msg line-offset (diff-xor reverse switched) t)))
1815 (defalias 'diff-mouse-goto-source 'diff-goto-source)
1817 (defun diff-goto-source (&optional other-file event)
1818 "Jump to the corresponding source line.
1819 `diff-jump-to-old-file' (or its opposite if the OTHER-FILE prefix arg
1820 is given) determines whether to jump to the old or the new file.
1821 If the prefix arg is bigger than 8 (for example with \\[universal-argument] \\[universal-argument])
1822 then `diff-jump-to-old-file' is also set, for the next invocations."
1823 (interactive (list current-prefix-arg last-input-event))
1824 ;; When pointing at a removal line, we probably want to jump to
1825 ;; the old location, and else to the new (i.e. as if reverting).
1826 ;; This is a convenient detail when using smerge-diff.
1827 (if event (posn-set-point (event-end event)))
1828 (let ((rev (not (save-excursion (beginning-of-line) (looking-at "[-<]")))))
1829 (pcase-let ((`(,buf ,line-offset ,pos ,src ,_dst ,switched)
1830 (diff-find-source-location other-file rev)))
1831 (pop-to-buffer buf)
1832 (goto-char (+ (car pos) (cdr src)))
1833 (diff-hunk-status-msg line-offset (diff-xor rev switched) t))))
1836 (defun diff-current-defun ()
1837 "Find the name of function at point.
1838 For use in `add-log-current-defun-function'."
1839 ;; Kill change-log-default-name so it gets recomputed each time, since
1840 ;; each hunk may belong to another file which may belong to another
1841 ;; directory and hence have a different ChangeLog file.
1842 (kill-local-variable 'change-log-default-name)
1843 (save-excursion
1844 (when (looking-at diff-hunk-header-re)
1845 (forward-line 1)
1846 (re-search-forward "^[^ ]" nil t))
1847 (pcase-let ((`(,buf ,_line-offset ,pos ,src ,dst ,switched)
1848 (ignore-errors ;Signals errors in place of prompting.
1849 ;; Use `noprompt' since this is used in which-func-mode
1850 ;; and such.
1851 (diff-find-source-location nil nil 'noprompt))))
1852 (when buf
1853 (beginning-of-line)
1854 (or (when (memq (char-after) '(?< ?-))
1855 ;; Cursor is pointing at removed text. This could be a removed
1856 ;; function, in which case, going to the source buffer will
1857 ;; not help since the function is now removed. Instead,
1858 ;; try to figure out the function name just from the
1859 ;; code-fragment.
1860 (let ((old (if switched dst src)))
1861 (with-temp-buffer
1862 (insert (car old))
1863 (funcall (buffer-local-value 'major-mode buf))
1864 (goto-char (+ (point-min) (cdr old)))
1865 (add-log-current-defun))))
1866 (with-current-buffer buf
1867 (goto-char (+ (car pos) (cdr src)))
1868 (add-log-current-defun)))))))
1870 (defun diff-ignore-whitespace-hunk ()
1871 "Re-diff the current hunk, ignoring whitespace differences."
1872 (interactive)
1873 (let* ((char-offset (- (point) (diff-beginning-of-hunk t)))
1874 (opts (pcase (char-after) (?@ "-bu") (?* "-bc") (_ "-b")))
1876 (error "Can't find line number"))
1877 (string-to-number (match-string 1))))
1878 (inhibit-read-only t)
1879 (hunk (delete-and-extract-region
1880 (point) (save-excursion (diff-end-of-hunk) (point))))
1882 (file1 (make-temp-file "diff1"))
1883 (file2 (make-temp-file "diff2"))
1884 (coding-system-for-read buffer-file-coding-system)
1885 old new)
1886 (unwind-protect
1887 (save-excursion
1888 (setq old (diff-hunk-text hunk nil char-offset))
1889 (setq new (diff-hunk-text hunk t char-offset))
1890 (write-region (concat lead (car old)) nil file1 nil 'nomessage)
1891 (write-region (concat lead (car new)) nil file2 nil 'nomessage)
1892 (with-temp-buffer
1893 (let ((status
1894 (call-process diff-command nil t nil
1895 opts file1 file2)))
1896 (pcase status
1897 (0 nil) ;Nothing to reformat.
1898 (1 (goto-char (point-min))
1899 ;; Remove the file-header.
1900 (when (re-search-forward diff-hunk-header-re nil t)
1901 (delete-region (point-min) (match-beginning 0))))
1902 (_ (goto-char (point-max))
1904 (insert hunk)))
1905 (setq hunk (buffer-string))
1906 (unless (memq status '(0 1))
1907 (error "Diff returned: %s" status)))))
1908 ;; Whatever happens, put back some equivalent text: either the new
1909 ;; one or the original one in case some error happened.
1910 (insert hunk)
1911 (delete-file file1)
1912 (delete-file file2))))
1914 ;;; Fine change highlighting.
1916 (defface diff-refine-change
1917 '((((class color) (min-colors 88) (background light))
1918 :background "#ffff55")
1919 (((class color) (min-colors 88) (background dark))
1920 :background "#aaaa22")
1921 (t :inverse-video t))
1922 "Face used for char-based changes shown by `diff-refine-hunk'."
1923 :group 'diff-mode)
1925 (defface diff-refine-removed
1926 '((default
1927 :inherit diff-refine-change)
1928 (((class color) (min-colors 88) (background light))
1929 :background "#ffbbbb")
1930 (((class color) (min-colors 88) (background dark))
1931 :background "#aa2222"))
1932 "Face used for removed characters shown by `diff-refine-hunk'."
1933 :group 'diff-mode
1934 :version "24.3")
1936 (defface diff-refine-added
1937 '((default
1938 :inherit diff-refine-change)
1939 (((class color) (min-colors 88) (background light))
1940 :background "#aaffaa")
1941 (((class color) (min-colors 88) (background dark))
1942 :background "#22aa22"))
1943 "Face used for added characters shown by `diff-refine-hunk'."
1944 :group 'diff-mode
1945 :version "24.3")
1947 (defun diff-refine-preproc ()
1948 (while (re-search-forward "^[+>]" nil t)
1949 ;; Remove spurious changes due to the fact that one side of the hunk is
1950 ;; marked with leading + or > and the other with leading - or <.
1951 ;; We used to replace all the prefix chars with " " but this only worked
1952 ;; when we did char-based refinement (or when using
1953 ;; smerge-refine-weight-hack) since otherwise, the `forward' motion done
1954 ;; in chopup do not necessarily do the same as the ones in highlight
1955 ;; since the "_" is not treated the same as " ".
1956 (replace-match (cdr (assq (char-before) '((?+ . "-") (?> . "<"))))))
1957 )
1959 (declare-function smerge-refine-subst "smerge-mode"
1960 (beg1 end1 beg2 end2 props-c &optional preproc props-r props-a))
1962 (defun diff-refine-hunk ()
1963 "Highlight changes of hunk at point at a finer granularity."
1964 (interactive)
1965 (require 'smerge-mode)
1966 (save-excursion
1967 (diff-beginning-of-hunk t)
1968 (let* ((start (point))
1969 (style (diff-hunk-style)) ;Skips the hunk header as well.
1970 (beg (point))
1971 (props-c '((diff-mode . fine) (face diff-refine-change)))
1972 (props-r '((diff-mode . fine) (face diff-refine-removed)))
1973 (props-a '((diff-mode . fine) (face diff-refine-added)))
1974 ;; Be careful to go back to `start' so diff-end-of-hunk gets
1975 ;; to read the hunk header's line info.
1976 (end (progn (goto-char start) (diff-end-of-hunk) (point))))
1978 (remove-overlays beg end 'diff-mode 'fine)
1980 (goto-char beg)
1981 (pcase style
1982 (`unified
1983 (while (re-search-forward
1984 (eval-when-compile
1989 end t)
1990 (smerge-refine-subst (match-beginning 0) (match-end 1)
1991 (match-end 1) (match-end 0)
1992 nil 'diff-refine-preproc props-r props-a)))
1993 (`context
1994 (let* ((middle (save-excursion (re-search-forward "^---")))
1995 (other middle))
1997 (smerge-refine-subst (match-beginning 0) (match-end 0)
1998 (save-excursion
1999 (goto-char other)
2001 (setq other (match-end 0))
2002 (match-beginning 0))
2003 other
2004 (if diff-use-changed-face props-c)
2005 'diff-refine-preproc
2006 (unless diff-use-changed-face props-r)
2007 (unless diff-use-changed-face props-a)))))
2008 (_ ;; Normal diffs.
2009 (let ((beg1 (1+ (point))))
2011 ;; It's a combined add&remove, so there's something to do.
2012 (smerge-refine-subst beg1 (match-beginning 0)
2013 (match-end 0) end
2014 nil 'diff-refine-preproc props-r props-a))))))))
2016 (defun diff-undo (&optional arg)
2017 "Perform `undo', ignoring the buffer's read-only status."
2018 (interactive "P")
2019 (let ((inhibit-read-only t))
2020 (undo arg)))
2022 (defun diff-add-change-log-entries-other-window ()
2023 "Iterate through the current diff and create ChangeLog entries.
2024 I.e. like `add-change-log-entry-other-window' but applied to all hunks."
2025 (interactive)
2026 ;; XXX: Currently add-change-log-entry-other-window is only called
2027 ;; once per hunk. Some hunks have multiple changes, it would be
2028 ;; good to call it for each change.
2029 (save-excursion
2030 (goto-char (point-min))
2031 (condition-case nil
2032 ;; Call add-change-log-entry-other-window for each hunk in
2033 ;; the diff buffer.
2034 (while (progn
2035 (diff-hunk-next)
2036 ;; Move to where the changes are,
2037 ;; `add-change-log-entry-other-window' works better in
2038 ;; that case.
2039 (re-search-forward
2041 ;; If the hunk is a context hunk with an empty first
2042 ;; half, recognize the "--- NNN,MMM ----" line
2044 ;; and skip to the next non-context line.
2046 nil t))
2047 (save-excursion
2048 ;; FIXME: this pops up windows of all the buffers.
2049 (add-change-log-entry nil nil t nil t)))
2050 ;; When there's no more hunks, diff-hunk-next signals an error.
2051 (error nil))))
2053 (defun diff-delete-trailing-whitespace (&optional other-file)
2054 "Remove trailing whitespace from lines modified in this diff.
2055 This edits both the current Diff mode buffer and the patched
2056 source file(s). If `diff-jump-to-old-file' is non-nil, edit the
2057 original (unpatched) source file instead. With a prefix argument
2058 OTHER-FILE, flip the choice of which source file to edit.
2060 If a file referenced in the diff has no buffer and needs to be
2061 fixed, visit it in a buffer."
2062 (interactive "P")
2063 (save-excursion
2064 (goto-char (point-min))
2065 (let* ((other (diff-xor other-file diff-jump-to-old-file))
2066 (modified-buffers nil)
2067 (style (save-excursion
2068 (when (re-search-forward diff-hunk-header-re nil t)
2069 (goto-char (match-beginning 0))
2070 (diff-hunk-style))))
2071 (regexp (concat "^[" (if other "-<" "+>") "!]"
2072 (if (eq style 'context) " " "")
2074 (inhibit-read-only t)
2075 (end-marker (make-marker))
2076 hunk-end)
2077 ;; Move to the first hunk.
2078 (re-search-forward diff-hunk-header-re nil 1)
2079 (while (progn (save-excursion
2080 (re-search-forward diff-hunk-header-re nil 1)
2081 (setq hunk-end (point)))
2082 (< (point) hunk-end))
2083 ;; For context diffs, search only in the appropriate half of
2084 ;; the hunk. For other diffs, search within the entire hunk.
2085 (if (not (eq style 'context))
2086 (set-marker end-marker hunk-end)
2087 (let ((mid-hunk
2088 (save-excursion
2089 (re-search-forward diff-context-mid-hunk-header-re hunk-end)
2090 (point))))
2091 (if other
2092 (set-marker end-marker mid-hunk)
2093 (goto-char mid-hunk)
2094 (set-marker end-marker hunk-end))))
2095 (while (re-search-forward regexp end-marker t)
2096 (let ((match-data (match-data)))
2097 (pcase-let ((`(,buf ,line-offset ,pos ,src ,_dst ,_switched)
2098 (diff-find-source-location other-file)))
2099 (when line-offset
2100 ;; Remove the whitespace in the Diff mode buffer.
2101 (set-match-data match-data)
2102 (replace-match "" t t nil 1)
2103 ;; Remove the whitespace in the source buffer.
2104 (with-current-buffer buf
2105 (save-excursion
2106 (goto-char (+ (car pos) (cdr src)))
2107 (beginning-of-line)
2109 (unless (memq buf modified-buffers)
2110 (push buf modified-buffers))
2111 (replace-match ""))))))))
2112 (goto-char hunk-end))
2113 (if modified-buffers
2114 (message "Deleted trailing whitespace from %s."
2115 (mapconcat (lambda (buf) (concat "`" (buffer-name buf) "'"))
2116 modified-buffers ", "))
2117 (message "No trailing whitespace to delete.")))))
2119 ;; provide the package
2120 (provide 'diff-mode)
2122 ;;; Old Change Log from when diff-mode wasn't part of Emacs:
2123 ;; Revision 1.11 1999/10/09 23:38:29 monnier
2124 ;; (diff-mode-load-hook): dropped.
2125 ;; (auto-mode-alist): also catch *.diffs.
2126 ;; (diff-find-file-name, diff-mode): add smarts to find the right file
2127 ;; for *.rej files (that lack any file name indication).
2128 ;;
2129 ;; Revision 1.10 1999/09/30 15:32:11 monnier
2130 ;; added support for "\ No newline at end of file".
2131 ;;
2132 ;; Revision 1.9 1999/09/15 00:01:13 monnier
2133 ;; - added basic `compile' support.
2134 ;; - have diff-kill-hunk call diff-kill-file if it's the only hunk.
2135 ;; - diff-kill-file now tries to kill the leading garbage as well.
2136 ;;
2137 ;; Revision 1.8 1999/09/13 21:10:09 monnier
2138 ;; - don't use CL in the autoloaded code
2139 ;; - accept diffs using -T
2140 ;;
2141 ;; Revision 1.7 1999/09/05 20:53:03 monnier
2142 ;; interface to ediff-patch
2143 ;;
2144 ;; Revision 1.6 1999/09/01 20:55:13 monnier
2145 ;; (ediff=patch-file): add bindings to call ediff-patch.
2146 ;; (diff-find-file-name): taken out of diff-goto-source.
2147 ;; (diff-unified->context, diff-context->unified, diff-reverse-direction,
2148 ;; diff-fixup-modifs): only use the region if a prefix arg is given.
2149 ;;
2150 ;; Revision 1.5 1999/08/31 19:18:52 monnier
2151 ;; (diff-beginning-of-file, diff-prev-file): fixed wrong parenthesis.
2152 ;;
2153 ;; Revision 1.4 1999/08/31 13:01:44 monnier
2154 ;; use `combine-after-change-calls' to minimize the slowdown of font-lock.
2155 ;;
2157 ;;; diff-mode.el ends here