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1 git-rebase(1)
2 =============
3
4 NAME
5 ----
6 git-rebase - Forward-port local commits to the updated upstream head
7
8 SYNOPSIS
9 --------
10 [verse]
11 'git rebase' [-i | --interactive] [options] [--onto <newbase>]
12 <upstream> [<branch>]
13 'git rebase' [-i | --interactive] [options] --onto <newbase>
14 --root [<branch>]
15
16 'git rebase' --continue | --skip | --abort
17
18 DESCRIPTION
19 -----------
20 If <branch> is specified, 'git rebase' will perform an automatic
21 `git checkout <branch>` before doing anything else. Otherwise
22 it remains on the current branch.
23
24 All changes made by commits in the current branch but that are not
25 in <upstream> are saved to a temporary area. This is the same set
26 of commits that would be shown by `git log <upstream>..HEAD` (or
27 `git log HEAD`, if --root is specified).
28
29 The current branch is reset to <upstream>, or <newbase> if the
30 --onto option was supplied. This has the exact same effect as
31 `git reset --hard <upstream>` (or <newbase>). ORIG_HEAD is set
32 to point at the tip of the branch before the reset.
33
34 The commits that were previously saved into the temporary area are
35 then reapplied to the current branch, one by one, in order. Note that
36 any commits in HEAD which introduce the same textual changes as a commit
37 in HEAD..<upstream> are omitted (i.e., a patch already accepted upstream
38 with a different commit message or timestamp will be skipped).
39
40 It is possible that a merge failure will prevent this process from being
41 completely automatic. You will have to resolve any such merge failure
42 and run `git rebase --continue`. Another option is to bypass the commit
43 that caused the merge failure with `git rebase --skip`. To restore the
44 original <branch> and remove the .git/rebase-apply working files, use the
45 command `git rebase --abort` instead.
46
47 Assume the following history exists and the current branch is "topic":
48
49 ------------
50 A---B---C topic
51 /
52 D---E---F---G master
53 ------------
54
55 From this point, the result of either of the following commands:
56
57
58 git rebase master
59 git rebase master topic
60
61 would be:
62
63 ------------
64 A'--B'--C' topic
65 /
66 D---E---F---G master
67 ------------
68
69 The latter form is just a short-hand of `git checkout topic`
70 followed by `git rebase master`.
71
72 If the upstream branch already contains a change you have made (e.g.,
73 because you mailed a patch which was applied upstream), then that commit
74 will be skipped. For example, running `git rebase master` on the
75 following history (in which A' and A introduce the same set of changes,
76 but have different committer information):
77
78 ------------
79 A---B---C topic
80 /
81 D---E---A'---F master
82 ------------
83
84 will result in:
85
86 ------------
87 B'---C' topic
88 /
89 D---E---A'---F master
90 ------------
91
92 Here is how you would transplant a topic branch based on one
93 branch to another, to pretend that you forked the topic branch
94 from the latter branch, using `rebase --onto`.
95
96 First let's assume your 'topic' is based on branch 'next'.
97 For example, a feature developed in 'topic' depends on some
98 functionality which is found in 'next'.
99
100 ------------
101 o---o---o---o---o master
102 \
103 o---o---o---o---o next
104 \
105 o---o---o topic
106 ------------
107
108 We want to make 'topic' forked from branch 'master'; for example,
109 because the functionality on which 'topic' depends was merged into the
110 more stable 'master' branch. We want our tree to look like this:
111
112 ------------
113 o---o---o---o---o master
114 | \
115 | o'--o'--o' topic
116 \
117 o---o---o---o---o next
118 ------------
119
120 We can get this using the following command:
121
122 git rebase --onto master next topic
123
124
125 Another example of --onto option is to rebase part of a
126 branch. If we have the following situation:
127
128 ------------
129 H---I---J topicB
130 /
131 E---F---G topicA
132 /
133 A---B---C---D master
134 ------------
135
136 then the command
137
138 git rebase --onto master topicA topicB
139
140 would result in:
141
142 ------------
143 H'--I'--J' topicB
144 /
145 | E---F---G topicA
146 |/
147 A---B---C---D master
148 ------------
149
150 This is useful when topicB does not depend on topicA.
151
152 A range of commits could also be removed with rebase. If we have
153 the following situation:
154
155 ------------
156 E---F---G---H---I---J topicA
157 ------------
158
159 then the command
160
161 git rebase --onto topicA~5 topicA~3 topicA
162
163 would result in the removal of commits F and G:
164
165 ------------
166 E---H'---I'---J' topicA
167 ------------
168
169 This is useful if F and G were flawed in some way, or should not be
170 part of topicA. Note that the argument to --onto and the <upstream>
171 parameter can be any valid commit-ish.
172
173 In case of conflict, 'git rebase' will stop at the first problematic commit
174 and leave conflict markers in the tree. You can use 'git diff' to locate
175 the markers (<<<<<<) and make edits to resolve the conflict. For each
176 file you edit, you need to tell git that the conflict has been resolved,
177 typically this would be done with
178
179
180 git add <filename>
181
182
183 After resolving the conflict manually and updating the index with the
184 desired resolution, you can continue the rebasing process with
185
186
187 git rebase --continue
188
189
190 Alternatively, you can undo the 'git rebase' with
191
192
193 git rebase --abort
194
195 CONFIGURATION
196 -------------
197
198 rebase.stat::
199 Whether to show a diffstat of what changed upstream since the last
200 rebase. False by default.
201
202 rebase.autosquash::
203 If set to true enable '--autosquash' option by default.
204
205 OPTIONS
206 -------
207 <newbase>::
208 Starting point at which to create the new commits. If the
209 --onto option is not specified, the starting point is
210 <upstream>. May be any valid commit, and not just an
211 existing branch name.
212 +
213 As a special case, you may use "A\...B" as a shortcut for the
214 merge base of A and B if there is exactly one merge base. You can
215 leave out at most one of A and B, in which case it defaults to HEAD.
216
217 <upstream>::
218 Upstream branch to compare against. May be any valid commit,
219 not just an existing branch name.
220
221 <branch>::
222 Working branch; defaults to HEAD.
223
224 --continue::
225 Restart the rebasing process after having resolved a merge conflict.
226
227 --abort::
228 Restore the original branch and abort the rebase operation.
229
230 --skip::
231 Restart the rebasing process by skipping the current patch.
232
233 -m::
234 --merge::
235 Use merging strategies to rebase. When the recursive (default) merge
236 strategy is used, this allows rebase to be aware of renames on the
237 upstream side.
238 +
239 Note that a rebase merge works by replaying each commit from the working
240 branch on top of the <upstream> branch. Because of this, when a merge
241 conflict happens, the side reported as 'ours' is the so-far rebased
242 series, starting with <upstream>, and 'theirs' is the working branch. In
243 other words, the sides are swapped.
244
245 -s <strategy>::
246 --strategy=<strategy>::
247 Use the given merge strategy.
248 If there is no `-s` option 'git merge-recursive' is used
249 instead. This implies --merge.
250 +
251 Because 'git rebase' replays each commit from the working branch
252 on top of the <upstream> branch using the given strategy, using
253 the 'ours' strategy simply discards all patches from the <branch>,
254 which makes little sense.
255
256 -X <strategy-option>::
257 --strategy-option=<strategy-option>::
258 Pass the <strategy-option> through to the merge strategy.
259 This implies `\--merge` and, if no strategy has been
260 specified, `-s recursive`. Note the reversal of 'ours' and
261 'theirs' as noted in above for the `-m` option.
262
263 -q::
264 --quiet::
265 Be quiet. Implies --no-stat.
266
267 -v::
268 --verbose::
269 Be verbose. Implies --stat.
270
271 --stat::
272 Show a diffstat of what changed upstream since the last rebase. The
273 diffstat is also controlled by the configuration option rebase.stat.
274
275 -n::
276 --no-stat::
277 Do not show a diffstat as part of the rebase process.
278
279 --no-verify::
280 This option bypasses the pre-rebase hook. See also linkgit:githooks[5].
281
282 --verify::
283 Allows the pre-rebase hook to run, which is the default. This option can
284 be used to override --no-verify. See also linkgit:githooks[5].
285
286 -C<n>::
287 Ensure at least <n> lines of surrounding context match before
288 and after each change. When fewer lines of surrounding
289 context exist they all must match. By default no context is
290 ever ignored.
291
292 -f::
293 --force-rebase::
294 Force the rebase even if the current branch is a descendant
295 of the commit you are rebasing onto. Normally non-interactive rebase will
296 exit with the message "Current branch is up to date" in such a
297 situation.
298 Incompatible with the --interactive option.
299 +
300 You may find this (or --no-ff with an interactive rebase) helpful after
301 reverting a topic branch merge, as this option recreates the topic branch with
302 fresh commits so it can be remerged successfully without needing to "revert
303 the reversion" (see the
304 link:howto/revert-a-faulty-merge.txt[revert-a-faulty-merge How-To] for details).
305
306 --ignore-whitespace::
307 --whitespace=<option>::
308 These flag are passed to the 'git apply' program
309 (see linkgit:git-apply[1]) that applies the patch.
310 Incompatible with the --interactive option.
311
312 --committer-date-is-author-date::
313 --ignore-date::
314 These flags are passed to 'git am' to easily change the dates
315 of the rebased commits (see linkgit:git-am[1]).
316 Incompatible with the --interactive option.
317
318 -i::
319 --interactive::
320 Make a list of the commits which are about to be rebased. Let the
321 user edit that list before rebasing. This mode can also be used to
322 split commits (see SPLITTING COMMITS below).
323
324 -p::
325 --preserve-merges::
326 Instead of ignoring merges, try to recreate them.
327 +
328 This uses the `--interactive` machinery internally, but combining it
329 with the `--interactive` option explicitly is generally not a good
330 idea unless you know what you are doing (see BUGS below).
331
332
333 --root::
334 Rebase all commits reachable from <branch>, instead of
335 limiting them with an <upstream>. This allows you to rebase
336 the root commit(s) on a branch. Must be used with --onto, and
337 will skip changes already contained in <newbase> (instead of
338 <upstream>). When used together with --preserve-merges, 'all'
339 root commits will be rewritten to have <newbase> as parent
340 instead.
341
342 --autosquash::
343 --no-autosquash::
344 When the commit log message begins with "squash! ..." (or
345 "fixup! ..."), and there is a commit whose title begins with
346 the same ..., automatically modify the todo list of rebase -i
347 so that the commit marked for squashing comes right after the
348 commit to be modified, and change the action of the moved
349 commit from `pick` to `squash` (or `fixup`).
350 +
351 This option is only valid when the '--interactive' option is used.
352 +
353 If the '--autosquash' option is enabled by default using the
354 configuration variable `rebase.autosquash`, this option can be
355 used to override and disable this setting.
356
357 --no-ff::
358 With --interactive, cherry-pick all rebased commits instead of
359 fast-forwarding over the unchanged ones. This ensures that the
360 entire history of the rebased branch is composed of new commits.
361 +
362 Without --interactive, this is a synonym for --force-rebase.
363 +
364 You may find this helpful after reverting a topic branch merge, as this option
365 recreates the topic branch with fresh commits so it can be remerged
366 successfully without needing to "revert the reversion" (see the
367 link:howto/revert-a-faulty-merge.txt[revert-a-faulty-merge How-To] for details).
368
369 include::merge-strategies.txt[]
370
371 NOTES
372 -----
373
374 You should understand the implications of using 'git rebase' on a
375 repository that you share. See also RECOVERING FROM UPSTREAM REBASE
376 below.
377
378 When the git-rebase command is run, it will first execute a "pre-rebase"
379 hook if one exists. You can use this hook to do sanity checks and
380 reject the rebase if it isn't appropriate. Please see the template
381 pre-rebase hook script for an example.
382
383 Upon completion, <branch> will be the current branch.
384
385 INTERACTIVE MODE
386 ----------------
387
388 Rebasing interactively means that you have a chance to edit the commits
389 which are rebased. You can reorder the commits, and you can
390 remove them (weeding out bad or otherwise unwanted patches).
391
392 The interactive mode is meant for this type of workflow:
393
394 1. have a wonderful idea
395 2. hack on the code
396 3. prepare a series for submission
397 4. submit
398
399 where point 2. consists of several instances of
400
401 a. regular use
402 1. finish something worthy of a commit
403 2. commit
404 b. independent fixup
405 1. realize that something does not work
406 2. fix that
407 3. commit it
408
409 Sometimes the thing fixed in b.2. cannot be amended to the not-quite
410 perfect commit it fixes, because that commit is buried deeply in a
411 patch series. That is exactly what interactive rebase is for: use it
412 after plenty of "a"s and "b"s, by rearranging and editing
413 commits, and squashing multiple commits into one.
414
415 Start it with the last commit you want to retain as-is:
416
417 git rebase -i <after-this-commit>
418
419 An editor will be fired up with all the commits in your current branch
420 (ignoring merge commits), which come after the given commit. You can
421 reorder the commits in this list to your heart's content, and you can
422 remove them. The list looks more or less like this:
423
424 -------------------------------------------
425 pick deadbee The oneline of this commit
426 pick fa1afe1 The oneline of the next commit
427 ...
428 -------------------------------------------
429
430 The oneline descriptions are purely for your pleasure; 'git rebase' will
431 not look at them but at the commit names ("deadbee" and "fa1afe1" in this
432 example), so do not delete or edit the names.
433
434 By replacing the command "pick" with the command "edit", you can tell
435 'git rebase' to stop after applying that commit, so that you can edit
436 the files and/or the commit message, amend the commit, and continue
437 rebasing.
438
439 If you just want to edit the commit message for a commit, replace the
440 command "pick" with the command "reword".
441
442 If you want to fold two or more commits into one, replace the command
443 "pick" for the second and subsequent commits with "squash" or "fixup".
444 If the commits had different authors, the folded commit will be
445 attributed to the author of the first commit. The suggested commit
446 message for the folded commit is the concatenation of the commit
447 messages of the first commit and of those with the "squash" command,
448 but omits the commit messages of commits with the "fixup" command.
449
450 'git rebase' will stop when "pick" has been replaced with "edit" or
451 when a command fails due to merge errors. When you are done editing
452 and/or resolving conflicts you can continue with `git rebase --continue`.
453
454 For example, if you want to reorder the last 5 commits, such that what
455 was HEAD~4 becomes the new HEAD. To achieve that, you would call
456 'git rebase' like this:
457
458 ----------------------
459 $ git rebase -i HEAD~5
460 ----------------------
461
462 And move the first patch to the end of the list.
463
464 You might want to preserve merges, if you have a history like this:
465
466 ------------------
467 X
468 \
469 A---M---B
470 /
471 ---o---O---P---Q
472 ------------------
473
474 Suppose you want to rebase the side branch starting at "A" to "Q". Make
475 sure that the current HEAD is "B", and call
476
477 -----------------------------
478 $ git rebase -i -p --onto Q O
479 -----------------------------
480
481 Reordering and editing commits usually creates untested intermediate
482 steps. You may want to check that your history editing did not break
483 anything by running a test, or at least recompiling at intermediate
484 points in history by using the "exec" command (shortcut "x"). You may
485 do so by creating a todo list like this one:
486
487 -------------------------------------------
488 pick deadbee Implement feature XXX
489 fixup f1a5c00 Fix to feature XXX
490 exec make
491 pick c0ffeee The oneline of the next commit
492 edit deadbab The oneline of the commit after
493 exec cd subdir; make test
494 ...
495 -------------------------------------------
496
497 The interactive rebase will stop when a command fails (i.e. exits with
498 non-0 status) to give you an opportunity to fix the problem. You can
499 continue with `git rebase --continue`.
500
501 The "exec" command launches the command in a shell (the one specified
502 in `$SHELL`, or the default shell if `$SHELL` is not set), so you can
503 use shell features (like "cd", ">", ";" ...). The command is run from
504 the root of the working tree.
505
506 SPLITTING COMMITS
507 -----------------
508
509 In interactive mode, you can mark commits with the action "edit". However,
510 this does not necessarily mean that 'git rebase' expects the result of this
511 edit to be exactly one commit. Indeed, you can undo the commit, or you can
512 add other commits. This can be used to split a commit into two:
513
514 - Start an interactive rebase with `git rebase -i <commit>^`, where
515 <commit> is the commit you want to split. In fact, any commit range
516 will do, as long as it contains that commit.
517
518 - Mark the commit you want to split with the action "edit".
519
520 - When it comes to editing that commit, execute `git reset HEAD^`. The
521 effect is that the HEAD is rewound by one, and the index follows suit.
522 However, the working tree stays the same.
523
524 - Now add the changes to the index that you want to have in the first
525 commit. You can use `git add` (possibly interactively) or
526 'git gui' (or both) to do that.
527
528 - Commit the now-current index with whatever commit message is appropriate
529 now.
530
531 - Repeat the last two steps until your working tree is clean.
532
533 - Continue the rebase with `git rebase --continue`.
534
535 If you are not absolutely sure that the intermediate revisions are
536 consistent (they compile, pass the testsuite, etc.) you should use
537 'git stash' to stash away the not-yet-committed changes
538 after each commit, test, and amend the commit if fixes are necessary.
539
540
541 RECOVERING FROM UPSTREAM REBASE
542 -------------------------------
543
544 Rebasing (or any other form of rewriting) a branch that others have
545 based work on is a bad idea: anyone downstream of it is forced to
546 manually fix their history. This section explains how to do the fix
547 from the downstream's point of view. The real fix, however, would be
548 to avoid rebasing the upstream in the first place.
549
550 To illustrate, suppose you are in a situation where someone develops a
551 'subsystem' branch, and you are working on a 'topic' that is dependent
552 on this 'subsystem'. You might end up with a history like the
553 following:
554
555 ------------
556 o---o---o---o---o---o---o---o---o master
557 \
558 o---o---o---o---o subsystem
559 \
560 *---*---* topic
561 ------------
562
563 If 'subsystem' is rebased against 'master', the following happens:
564
565 ------------
566 o---o---o---o---o---o---o---o master
567 \ \
568 o---o---o---o---o o'--o'--o'--o'--o' subsystem
569 \
570 *---*---* topic
571 ------------
572
573 If you now continue development as usual, and eventually merge 'topic'
574 to 'subsystem', the commits from 'subsystem' will remain duplicated forever:
575
576 ------------
577 o---o---o---o---o---o---o---o master
578 \ \
579 o---o---o---o---o o'--o'--o'--o'--o'--M subsystem
580 \ /
581 *---*---*-..........-*--* topic
582 ------------
583
584 Such duplicates are generally frowned upon because they clutter up
585 history, making it harder to follow. To clean things up, you need to
586 transplant the commits on 'topic' to the new 'subsystem' tip, i.e.,
587 rebase 'topic'. This becomes a ripple effect: anyone downstream from
588 'topic' is forced to rebase too, and so on!
589
590 There are two kinds of fixes, discussed in the following subsections:
591
592 Easy case: The changes are literally the same.::
593
594 This happens if the 'subsystem' rebase was a simple rebase and
595 had no conflicts.
596
597 Hard case: The changes are not the same.::
598
599 This happens if the 'subsystem' rebase had conflicts, or used
600 `\--interactive` to omit, edit, squash, or fixup commits; or
601 if the upstream used one of `commit \--amend`, `reset`, or
602 `filter-branch`.
603
604
605 The easy case
606 ~~~~~~~~~~~~~
607
608 Only works if the changes (patch IDs based on the diff contents) on
609 'subsystem' are literally the same before and after the rebase
610 'subsystem' did.
611
612 In that case, the fix is easy because 'git rebase' knows to skip
613 changes that are already present in the new upstream. So if you say
614 (assuming you're on 'topic')
615 ------------
616 $ git rebase subsystem
617 ------------
618 you will end up with the fixed history
619 ------------
620 o---o---o---o---o---o---o---o master
621 \
622 o'--o'--o'--o'--o' subsystem
623 \
624 *---*---* topic
625 ------------
626
627
628 The hard case
629 ~~~~~~~~~~~~~
630
631 Things get more complicated if the 'subsystem' changes do not exactly
632 correspond to the ones before the rebase.
633
634 NOTE: While an "easy case recovery" sometimes appears to be successful
635 even in the hard case, it may have unintended consequences. For
636 example, a commit that was removed via `git rebase
637 \--interactive` will be **resurrected**!
638
639 The idea is to manually tell 'git rebase' "where the old 'subsystem'
640 ended and your 'topic' began", that is, what the old merge-base
641 between them was. You will have to find a way to name the last commit
642 of the old 'subsystem', for example:
643
644 * With the 'subsystem' reflog: after 'git fetch', the old tip of
645 'subsystem' is at `subsystem@\{1}`. Subsequent fetches will
646 increase the number. (See linkgit:git-reflog[1].)
647
648 * Relative to the tip of 'topic': knowing that your 'topic' has three
649 commits, the old tip of 'subsystem' must be `topic~3`.
650
651 You can then transplant the old `subsystem..topic` to the new tip by
652 saying (for the reflog case, and assuming you are on 'topic' already):
653 ------------
654 $ git rebase --onto subsystem subsystem@{1}
655 ------------
656
657 The ripple effect of a "hard case" recovery is especially bad:
658 'everyone' downstream from 'topic' will now have to perform a "hard
659 case" recovery too!
660
661
662 BUGS
663 ----
664 The todo list presented by `--preserve-merges --interactive` does not
665 represent the topology of the revision graph. Editing commits and
666 rewording their commit messages should work fine, but attempts to
667 reorder commits tend to produce counterintuitive results.
668
669 For example, an attempt to rearrange
670 ------------
671 1 --- 2 --- 3 --- 4 --- 5
672 ------------
673 to
674 ------------
675 1 --- 2 --- 4 --- 3 --- 5
676 ------------
677 by moving the "pick 4" line will result in the following history:
678 ------------
679 3
680 /
681 1 --- 2 --- 4 --- 5
682 ------------
683
684 Authors
685 ------
686 Written by Junio C Hamano <gitster@pobox.com> and
687 Johannes E. Schindelin <johannes.schindelin@gmx.de>
688
689 Documentation
690 --------------
691 Documentation by Junio C Hamano and the git-list <git@vger.kernel.org>.
692
693 GIT
694 ---
695 Part of the linkgit:git[1] suite