2 .\" wiggle - apply rejected patches
4 .\" Copyright (C) 2003 Neil Brown <neilb@cse.unsw.edu.au>
5 .\" Copyright (C) 2010-2013 Neil Brown <neilb@suse.de>
6 .\" Copyright (C) 2018-2019 Neil Brown <neil@brown.name>
9 .\" This program is free software; you can redistribute it and/or modify
10 .\" it under the terms of the GNU General Public License as published by
11 .\" the Free Software Foundation; either version 2 of the License, or
12 .\" (at your option) any later version.
14 .\" This program is distributed in the hope that it will be useful,
15 .\" but WITHOUT ANY WARRANTY; without even the implied warranty of
16 .\" MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
17 .\" GNU General Public License for more details.
19 .\" You should have received a copy of the GNU General Public License
20 .\" along with this program.
22 .\" Author: Neil Brown
23 .\" Email: <neil@brown.name>
27 wiggle \- apply rejected patches and perform word-wise diffs
29 .BI wiggle " [function] [options] file [files]"
33 is to apply a patch to a file in a similar manner to the
37 The distinctive difference of
39 is that it will attempt to apply a patch even if the "before" part of
40 the patch doesn't match the target file perfectly.
41 This is achieved by breaking the file and patch into words and finding
42 the best alignment of words in the file with words in the patch.
43 Once this alignment has been found, any differences (word-wise) in the
44 patch are applied to the file as best as possible.
48 will (in some cases) detect changes that have already been applied,
52 ensures that every change in the patch is applied to the target
53 file somehow. If a particular change cannot be made in the file, the
54 file is annotated to show where the change should be made in a similar
60 Each annotation contains 3 components: a portion of the original file
61 where the change should be applied, a portion of the patch that
62 couldn't be matched precisely in the file, and the text that should
63 replace that portion of the patch. These are separated by lines
64 containing precisely 7 identical characters, either '<', '|', '=',
65 or '>', possibly followed by a descriptive word. So
70 Some portion of the original file
74 text to replace it with
79 indicates that "text to replace" should be replaced by "text to
80 replace it with" somewhere in the portion of the original file.
83 was not able to find a place to make this change.
86 can also produce conflict reports showing only the words that are
87 involved rather than showing whole lines.
88 In this case the output looks like:
91 <<<---original|||old===new--->>>
98 to apply some patch, and to collect a list of rejects by monitoring
99 the error messages from patch. Then for each file for which a
100 reject was found, run
102 wiggle \-\-replace originalfile originalfile.rej
104 Finally each file must be examined to resolve any unresolved
105 conflicts, and to make sure the applied patch is semantically correct.
107 Alternately, the original patch file can be fed to the
111 wiggle \-B < patchfile
113 This will allow the changes and conflicts to be inspected and, to some
114 extent, modified; and then the results can be saved.
116 The following options are understood by
118 Some of these are explained in more detail in the following sections
119 on MERGE, DIFF, EXTRACT, and BROWSE.
121 .BR \-m ", " \-\-merge
122 Select the "merge" function. This is the default function.
124 .BR \-d ", " \-\-diff
125 Select the "diff" function. This displays the differences between
126 files. This can be given after
128 (see below) in which case a patch or diff of two files can be viewed
129 without the originals.
131 .BR \-x ", " \-\-extract
132 Select the "extract" function. This extracts one branch of a patch or
135 .BR \-B ", " \-\-browse
136 Select the "browse" function. This is similar to "merge" (or "diff")
137 only with a different presentation. Instead of the result simply
138 being sent to standard output, it is presented using an ncurses-based
139 GUI so that each hunk of the patch can be examined to understand what
140 conflicts where involved and what needed to be ignored in order of the
141 patch to be wiggled in to place.
143 .BR \-w ", " \-\-words
144 Request that all operations and display be word based. This is the
145 default for the "diff" function.
147 .BR \-l ", " \-\-lines
148 Request that all operations and display be line based.
150 .BR \-b ", " \-\-ignore\-blanks
151 De-emphasise white space (space, tab, and newline) is determining
152 differences and changes.
155 Normally white space is treated like a word which can be matched or
156 changed by a patch. When this flag is in force, white space serves
157 only as a separator between other words and is not matched itself.
158 The effect of this is that changes in the amount of white space are
159 not treated as significant.
161 To be precise, any white space is combined with the preceding word
162 or, in the case of leading space on a line, with the following word.
163 However it is not involved in any comparisons of that word. If a patch
164 deletes a word, the attached white space is deleted as well. If a
165 patch adds a word, the attached white space is added as well.
167 An empty line, or one that contains only blanks, will be treated as a
168 single word that will match any other blank line, no matter how many
177 .BR \-p ", " \-\-patch
178 Treat the last named file as a patch instead of a file (with \-\-diff)
179 or a merge (\-\-extract).
186 requires there be exactly one file which is a patch and which can
187 contain patches to multiple files. The patches are merged into each
190 mode, this usage requires the
192 option as writing lots of merged files to standard-out is impractical.
195 When processing a multi-file patch,
197 can be followed by a numeric argument indicating how many file name
198 components should be stripped from files named in the patch file. If no
199 numeric argument is given,
201 will deduce an appropriate number based what files are present in the
205 .BR \-r ", " \-\-replace
206 Normally the merged output is written to standard-output. With
208 the original file is replaced with the merge output.
213 to always save the resulting merge when exiting.
216 Normally when an original file is replaced with the merged result, that
217 file is renamed to have a ".porig" extension, so that it is preserved.
218 If you don't want to keep the original, use this option to suppress
221 .BR \-o ", " \-\-output=
222 Rather than writing the result to stdout or to replace the original
223 file, this requests that the output be written to the given file.
224 This is only meaningful with
228 when given a single merge to browse.
231 This option overrides
235 .BR \-R ", " \-\-reverse
238 function, swap the files before calculating
246 attempts to revert changes rather than apply them.
248 .BR \-i ", " \-\-no\-ignore
249 Normally wiggle will ignore changes in the patch which appear to
250 already have been applied in the original. With this flag those
251 changes are reported as conflicts rather than being ignored.
253 .BR \-W ", " \-\-show\-wiggles
256 conflicts that can be wiggled into place are reported as conflicts
257 with an extra stanza which shows what the result would be if this flag
258 had not been used. The extra stanza is introduce with a line
259 containing 7 ampersand
266 Some portion of the original file
270 text to replace it with
272 Text that would result from a successful wiggle
278 .B \-\-report\-wiggles
279 If a merge is successful in applying all changes, it will normally exit
280 with a success status (0), only reporting failure (1) if a conflict
281 occurred and was annotated. With
282 .B \-\-report\-wiggles
284 will also report failure if any changes had to be wiggled in. This
287 is used for automatic merges as with
289 If any wiggles happen,
291 will report the failure, and the results can be examined to confirm
294 .BR \-h ", " \-\-help
295 Print a simple help message. If given after one of the function
301 help specific to that function is displayed.
303 .BR \-V ", " \-\-version
304 Display the version number of
307 .BR \-v ", " \-\-verbose
308 Enable verbose mode. Currently this makes no difference.
310 .BR \-q ", " \-\-quiet
311 Enable quiet mode. This suppresses the message from the merge
312 function when there are unresolvable conflicts.
315 can divide a text into lines or words when performing it's tasks.
316 A line is simply a string of characters terminated by a newline.
317 A word is either a maximal contiguous string of alphanumerics
318 (including underscore), a maximal contiguous string of space or tab
319 characters, or any other single character.
321 The merge function modifies a given text by finding all changes between
322 two other texts and imposing those changes on the given text.
326 focuses on which words have changed so as to maximise the possibility
327 of finding a good match in the given text for the context of a given
328 change. However it can consider only whole lines instead.
331 extracts the three texts that it needs from files listed on the
332 command line. Either 1, 2, or 3 files may be listed, and any one of
333 them may be a lone hyphen signifying standard-input.
335 If one file is given and the
337 option is not present, the file is treated as a
339 file, i.e. the output of "merge \-A" or "wiggle". Such a file
340 implicitly contains three streams and these are extracted and
343 If two files are given, then the first simply contains the primary
344 text, and the second is treated as a patch file (the output of "diff\ \-u"
345 or "diff\ \-c", or a ".rej" file from
347 and the two other texts
348 are extracted from that.
350 If one file is given together with the
352 option, the file is treated as a patch file containing the names of
353 the files that it patches. In this case multiple merge operations can
354 happen and each takes one stream from a file named in the patch, and
355 the other two from the patch itself. The
357 option is required and the results are written back to the
360 Finally if three files are listed, they are taken to contain the given
361 text and the two other texts, in order.
363 Normally the result of the merge is written to standard-output.
366 flag is given, the output is written to a file
367 which replaces the original given file. In this case the original file
368 will normally be renamed to have a
370 suffix (for "patched original" which makes sense if you first use
372 to apply a patch, and then use
374 to wiggle the rejects in). This can be suppressed with the
380 option is given with a file name, the output will be written to that
381 file. In this case no backup is created.
383 If no errors occur (such as file access errors)
385 will exit with a status of 0 if all changes were successfully merged,
386 and with an exit status of 1 and a brief message if any changes could
387 not be fully merged and were instead inserted as annotations.
389 .B \-\-report\-wiggles
394 will also exist with status of 1 if any changes had to be wiggled in
395 even though this was successful.
397 The merge function can operate in three different modes with respect
402 option, whole lines are compared and any conflicts
403 are reported as whole lines that need to be replaced.
407 option, individual words are compared and any
408 conflicts are reported just covering the words affected. This uses
409 the \f(CW <<<|||===>>> \fP conflict format.
411 Without either of these options, a hybrid approach is taken.
412 Individual words are compared and merged, but when a conflict is found
413 the whole surrounding line is reported as being in conflict.
416 will ensure that every change between the two other texts is reflected
417 in the result of the merge somehow. There are four different ways
418 that a change can be reflected.
426 is found at a suitable place in the original file, it is
429 This includes the possibility that
436 If a change is found which simply adds
438 and the text immediately preceding and following the insertion are
439 found adjacent in the original file in a suitable place, then
441 is inserted between those adjacent texts.
443 If a change is found which changes
447 and this appears (based on context) to align with
449 in the original, then it is assumed that this change has already been
450 applied, and the change is ignored. When this happens, a message
451 reflecting the number of ignored changes is printed by
453 This optimisation can be suppressed with the
457 If a change is found that does not fit any of the above possibilities,
458 then a conflict is reported as described earlier.
460 The diff function is provided primarily to allow inspection of the
463 calculated between texts and that it uses for performing a merge.
465 The output of the diff function is similar to the unified output of
466 diff. However while diff does not output long stretches of common text,
468 diff mode outputs everything.
470 When calculating a word-based alignment (the default),
472 may need to show these word-based differences. This is done using an
473 extension to the unified-diff format. If a line starts with a
474 vertical bar, then it may contain sections surrounded by special
475 multi-character brackets. The brackets "<<<++" and "++>>>" surround
476 added text while "<<<--" and "-->>>" surround removed text.
479 can be given the two texts to compare in one of three ways.
481 If only one file is given, then it is treated as a patch and the two
482 branches of that patch are compared. This effectively allows a patch
483 to be refined from a line-based patch to a word-based patch.
485 If two files are given, then they are normally assumed to be simple
486 texts to be compared.
488 If two files are given along with the \-\-patch option, then the second
489 file is assumed to be a patch and either the first (with \-1) or the
490 second (with \-2) branch is extracted and compared with text found in
493 This last option causes
495 to apply a "best-fit" algorithm for aligning patch hunks with the
496 file before computing the differences. This algorithm is used when
497 merging a patch with a file, and its value can be seen by comparing
498 the difference produced this way with the difference produced by first
499 extracting one branch of a patch into a file, and then computing the
500 difference of that file with the main file.
502 The extract function of
504 simply exposes the internal functionality for extracting one branch of
505 a patch or a merge file.
507 Precisely one file should be given, and it will be assumed to be a
510 is given, in which case a patch is assumed.
512 The choice of branch in made by providing one of
517 with obvious meanings.
519 The browse function of
521 presents the result of a merge or (with
523 a diff in a text-based GUI that can be
524 navigated using keystrokes similar to
529 The browser allows each of the two or three streams to be viewed individually
530 with colours used to highlight different sorts of text - green for
531 added text, red for deleted text etc. It can also show the patch by
532 itself, the full result of the merge, or the merge and the patch
535 The browser provides a number of context-sensitive help pages which
536 can be accessed by typing '?'
538 The top right of the GUI will report the type of text under the
539 cursor, which is also indicated by the colour of the text. Options
540 are Unchanged, Changed, Unmatched, Extraneous, AlreadyApplied and
541 Conflict. If the meanings of these are clear a little
542 experimentations should help.
544 A limited amount of editing is permitted while in
546 mode. Currently text that is unwanted can be discarded with
548 This will convert a Conflict or Change to Unchanged, and an Unmatched
549 to Changed (which effectively changes it to the empty string).
550 Similarly a text can be marked as wanted with
552 This will convert a Conflict or Extraneous to Changed. Using the same
553 key again will revert the change.
555 Finally, the uppercase
557 will revert all changes on the current line.
559 To make more sweeping changes you can use
561 which runs an editor, preferring
565 if they are set in the environment.
567 If you make any changes, then wiggle will ask you if you want
568 to save the changes, even if
572 Caution should always be exercised when applying a rejected patch with
576 rejects a patch, it does so for a good reason. Even though
578 may be able to find a believable place to apply each textual change,
579 there is no guarantee that the result is correct in any semantic
580 sense. The result should always be inspected to make sure it is
583 .B " wiggle \-\-replace file file.rej"
585 This is the normal usage of
587 and will take any changes in
591 could not apply, and merge them into
594 .B " wiggle \-dp1 file file.rej"
596 This will perform a word-wise comparison between the
600 branch of the diff in
602 and display the differences. This allows you to see where a given
605 .B " wiggle \-\-merge \-\-help"
607 Get help about the merge function of
610 .B " wiggle \-\-browse \-\-patch update.patch"
614 file for patches and present a list of patched files which can be
615 browsed to examine each patch in detail.
618 can be integrated with
620 so that it is used as the default merge tool and diff tool.
621 This can be achieved by adding the following lines to
623 in the user's home directory.
627 name = "Wiggle flexible merging"
628 driver = wiggle \-o %A %A %O %B
633 cmd = wiggle \-B \-o $MERGED $LOCAL $BASE $REMOTE
635 cmd = wiggle \-Bd $LOCAL $REMOTE
649 for merges (which may be dangerous), you can add
656 .BR $HOME/.config/git/attributes .
660 was inspired by the following quote.
663 The problem I find is that I often want to take
664 (file1+patch) -> file2,
665 when I don't have file1. But merge tools want to take
666 (file1|file2) -> file3.
667 I haven't seen a graphical tool which helps you to wiggle a patch
670 \-\- Andrew Morton - 2002
675 cannot read the extended unified-diff output that it produces for
679 cannot read the word-based merge format that it produces for \-\-merge
683 does not understand unicode and so will treat all non-ASCII characters
684 much the same as it treats punctuation - it will treat each one
685 as a separate word. The browser will not display non-ASCII characters
688 Neil Brown at Computer Science and Engineering at
689 The University of New South Wales, Sydney, Australia;
690 and later at SUSE, still in Sydney, Australia.
698 .IR gitattributes (5).
git / wiggle.git / blob