rebase docs: recommend `-r` over `-p`
[git/git.git] / Documentation / git-rebase.txt
1 git-rebase(1)
2 =============
3
4 NAME
5 ----
6 git-rebase - Reapply commits on top of another base tip
7
8 SYNOPSIS
9 --------
10 [verse]
11 'git rebase' [-i | --interactive] [<options>] [--exec <cmd>] [--onto <newbase>]
12 [<upstream> [<branch>]]
13 'git rebase' [-i | --interactive] [<options>] [--exec <cmd>] [--onto <newbase>]
14 --root [<branch>]
15 'git rebase' --continue | --skip | --abort | --quit | --edit-todo | --show-current-patch
16
17 DESCRIPTION
18 -----------
19 If <branch> is specified, 'git rebase' will perform an automatic
20 `git checkout <branch>` before doing anything else. Otherwise
21 it remains on the current branch.
22
23 If <upstream> is not specified, the upstream configured in
24 branch.<name>.remote and branch.<name>.merge options will be used (see
25 linkgit:git-config[1] for details) and the `--fork-point` option is
26 assumed. If you are currently not on any branch or if the current
27 branch does not have a configured upstream, the rebase will abort.
28
29 All changes made by commits in the current branch but that are not
30 in <upstream> are saved to a temporary area. This is the same set
31 of commits that would be shown by `git log <upstream>..HEAD`; or by
32 `git log 'fork_point'..HEAD`, if `--fork-point` is active (see the
33 description on `--fork-point` below); or by `git log HEAD`, if the
34 `--root` option is specified.
35
36 The current branch is reset to <upstream>, or <newbase> if the
37 --onto option was supplied. This has the exact same effect as
38 `git reset --hard <upstream>` (or <newbase>). ORIG_HEAD is set
39 to point at the tip of the branch before the reset.
40
41 The commits that were previously saved into the temporary area are
42 then reapplied to the current branch, one by one, in order. Note that
43 any commits in HEAD which introduce the same textual changes as a commit
44 in HEAD..<upstream> are omitted (i.e., a patch already accepted upstream
45 with a different commit message or timestamp will be skipped).
46
47 It is possible that a merge failure will prevent this process from being
48 completely automatic. You will have to resolve any such merge failure
49 and run `git rebase --continue`. Another option is to bypass the commit
50 that caused the merge failure with `git rebase --skip`. To check out the
51 original <branch> and remove the .git/rebase-apply working files, use the
52 command `git rebase --abort` instead.
53
54 Assume the following history exists and the current branch is "topic":
55
56 ------------
57 A---B---C topic
58 /
59 D---E---F---G master
60 ------------
61
62 From this point, the result of either of the following commands:
63
64
65 git rebase master
66 git rebase master topic
67
68 would be:
69
70 ------------
71 A'--B'--C' topic
72 /
73 D---E---F---G master
74 ------------
75
76 *NOTE:* The latter form is just a short-hand of `git checkout topic`
77 followed by `git rebase master`. When rebase exits `topic` will
78 remain the checked-out branch.
79
80 If the upstream branch already contains a change you have made (e.g.,
81 because you mailed a patch which was applied upstream), then that commit
82 will be skipped. For example, running `git rebase master` on the
83 following history (in which `A'` and `A` introduce the same set of changes,
84 but have different committer information):
85
86 ------------
87 A---B---C topic
88 /
89 D---E---A'---F master
90 ------------
91
92 will result in:
93
94 ------------
95 B'---C' topic
96 /
97 D---E---A'---F master
98 ------------
99
100 Here is how you would transplant a topic branch based on one
101 branch to another, to pretend that you forked the topic branch
102 from the latter branch, using `rebase --onto`.
103
104 First let's assume your 'topic' is based on branch 'next'.
105 For example, a feature developed in 'topic' depends on some
106 functionality which is found in 'next'.
107
108 ------------
109 o---o---o---o---o master
110 \
111 o---o---o---o---o next
112 \
113 o---o---o topic
114 ------------
115
116 We want to make 'topic' forked from branch 'master'; for example,
117 because the functionality on which 'topic' depends was merged into the
118 more stable 'master' branch. We want our tree to look like this:
119
120 ------------
121 o---o---o---o---o master
122 | \
123 | o'--o'--o' topic
124 \
125 o---o---o---o---o next
126 ------------
127
128 We can get this using the following command:
129
130 git rebase --onto master next topic
131
132
133 Another example of --onto option is to rebase part of a
134 branch. If we have the following situation:
135
136 ------------
137 H---I---J topicB
138 /
139 E---F---G topicA
140 /
141 A---B---C---D master
142 ------------
143
144 then the command
145
146 git rebase --onto master topicA topicB
147
148 would result in:
149
150 ------------
151 H'--I'--J' topicB
152 /
153 | E---F---G topicA
154 |/
155 A---B---C---D master
156 ------------
157
158 This is useful when topicB does not depend on topicA.
159
160 A range of commits could also be removed with rebase. If we have
161 the following situation:
162
163 ------------
164 E---F---G---H---I---J topicA
165 ------------
166
167 then the command
168
169 git rebase --onto topicA~5 topicA~3 topicA
170
171 would result in the removal of commits F and G:
172
173 ------------
174 E---H'---I'---J' topicA
175 ------------
176
177 This is useful if F and G were flawed in some way, or should not be
178 part of topicA. Note that the argument to --onto and the <upstream>
179 parameter can be any valid commit-ish.
180
181 In case of conflict, 'git rebase' will stop at the first problematic commit
182 and leave conflict markers in the tree. You can use 'git diff' to locate
183 the markers (<<<<<<) and make edits to resolve the conflict. For each
184 file you edit, you need to tell Git that the conflict has been resolved,
185 typically this would be done with
186
187
188 git add <filename>
189
190
191 After resolving the conflict manually and updating the index with the
192 desired resolution, you can continue the rebasing process with
193
194
195 git rebase --continue
196
197
198 Alternatively, you can undo the 'git rebase' with
199
200
201 git rebase --abort
202
203 CONFIGURATION
204 -------------
205
206 include::config/rebase.txt[]
207
208 OPTIONS
209 -------
210 --onto <newbase>::
211 Starting point at which to create the new commits. If the
212 --onto option is not specified, the starting point is
213 <upstream>. May be any valid commit, and not just an
214 existing branch name.
215 +
216 As a special case, you may use "A\...B" as a shortcut for the
217 merge base of A and B if there is exactly one merge base. You can
218 leave out at most one of A and B, in which case it defaults to HEAD.
219
220 <upstream>::
221 Upstream branch to compare against. May be any valid commit,
222 not just an existing branch name. Defaults to the configured
223 upstream for the current branch.
224
225 <branch>::
226 Working branch; defaults to HEAD.
227
228 --continue::
229 Restart the rebasing process after having resolved a merge conflict.
230
231 --abort::
232 Abort the rebase operation and reset HEAD to the original
233 branch. If <branch> was provided when the rebase operation was
234 started, then HEAD will be reset to <branch>. Otherwise HEAD
235 will be reset to where it was when the rebase operation was
236 started.
237
238 --quit::
239 Abort the rebase operation but HEAD is not reset back to the
240 original branch. The index and working tree are also left
241 unchanged as a result.
242
243 --keep-empty::
244 Keep the commits that do not change anything from its
245 parents in the result.
246 +
247 See also INCOMPATIBLE OPTIONS below.
248
249 --allow-empty-message::
250 By default, rebasing commits with an empty message will fail.
251 This option overrides that behavior, allowing commits with empty
252 messages to be rebased.
253 +
254 See also INCOMPATIBLE OPTIONS below.
255
256 --skip::
257 Restart the rebasing process by skipping the current patch.
258
259 --edit-todo::
260 Edit the todo list during an interactive rebase.
261
262 --show-current-patch::
263 Show the current patch in an interactive rebase or when rebase
264 is stopped because of conflicts. This is the equivalent of
265 `git show REBASE_HEAD`.
266
267 -m::
268 --merge::
269 Use merging strategies to rebase. When the recursive (default) merge
270 strategy is used, this allows rebase to be aware of renames on the
271 upstream side.
272 +
273 Note that a rebase merge works by replaying each commit from the working
274 branch on top of the <upstream> branch. Because of this, when a merge
275 conflict happens, the side reported as 'ours' is the so-far rebased
276 series, starting with <upstream>, and 'theirs' is the working branch. In
277 other words, the sides are swapped.
278 +
279 See also INCOMPATIBLE OPTIONS below.
280
281 -s <strategy>::
282 --strategy=<strategy>::
283 Use the given merge strategy.
284 If there is no `-s` option 'git merge-recursive' is used
285 instead. This implies --merge.
286 +
287 Because 'git rebase' replays each commit from the working branch
288 on top of the <upstream> branch using the given strategy, using
289 the 'ours' strategy simply empties all patches from the <branch>,
290 which makes little sense.
291 +
292 See also INCOMPATIBLE OPTIONS below.
293
294 -X <strategy-option>::
295 --strategy-option=<strategy-option>::
296 Pass the <strategy-option> through to the merge strategy.
297 This implies `--merge` and, if no strategy has been
298 specified, `-s recursive`. Note the reversal of 'ours' and
299 'theirs' as noted above for the `-m` option.
300 +
301 See also INCOMPATIBLE OPTIONS below.
302
303 -S[<keyid>]::
304 --gpg-sign[=<keyid>]::
305 GPG-sign commits. The `keyid` argument is optional and
306 defaults to the committer identity; if specified, it must be
307 stuck to the option without a space.
308
309 -q::
310 --quiet::
311 Be quiet. Implies --no-stat.
312
313 -v::
314 --verbose::
315 Be verbose. Implies --stat.
316
317 --stat::
318 Show a diffstat of what changed upstream since the last rebase. The
319 diffstat is also controlled by the configuration option rebase.stat.
320
321 -n::
322 --no-stat::
323 Do not show a diffstat as part of the rebase process.
324
325 --no-verify::
326 This option bypasses the pre-rebase hook. See also linkgit:githooks[5].
327
328 --verify::
329 Allows the pre-rebase hook to run, which is the default. This option can
330 be used to override --no-verify. See also linkgit:githooks[5].
331
332 -C<n>::
333 Ensure at least <n> lines of surrounding context match before
334 and after each change. When fewer lines of surrounding
335 context exist they all must match. By default no context is
336 ever ignored.
337 +
338 See also INCOMPATIBLE OPTIONS below.
339
340 --no-ff::
341 --force-rebase::
342 -f::
343 Individually replay all rebased commits instead of fast-forwarding
344 over the unchanged ones. This ensures that the entire history of
345 the rebased branch is composed of new commits.
346 +
347 You may find this helpful after reverting a topic branch merge, as this option
348 recreates the topic branch with fresh commits so it can be remerged
349 successfully without needing to "revert the reversion" (see the
350 link:howto/revert-a-faulty-merge.html[revert-a-faulty-merge How-To] for
351 details).
352
353 --fork-point::
354 --no-fork-point::
355 Use reflog to find a better common ancestor between <upstream>
356 and <branch> when calculating which commits have been
357 introduced by <branch>.
358 +
359 When --fork-point is active, 'fork_point' will be used instead of
360 <upstream> to calculate the set of commits to rebase, where
361 'fork_point' is the result of `git merge-base --fork-point <upstream>
362 <branch>` command (see linkgit:git-merge-base[1]). If 'fork_point'
363 ends up being empty, the <upstream> will be used as a fallback.
364 +
365 If either <upstream> or --root is given on the command line, then the
366 default is `--no-fork-point`, otherwise the default is `--fork-point`.
367
368 --ignore-whitespace::
369 --whitespace=<option>::
370 These flag are passed to the 'git apply' program
371 (see linkgit:git-apply[1]) that applies the patch.
372 +
373 See also INCOMPATIBLE OPTIONS below.
374
375 --committer-date-is-author-date::
376 --ignore-date::
377 These flags are passed to 'git am' to easily change the dates
378 of the rebased commits (see linkgit:git-am[1]).
379 +
380 See also INCOMPATIBLE OPTIONS below.
381
382 --signoff::
383 Add a Signed-off-by: trailer to all the rebased commits. Note
384 that if `--interactive` is given then only commits marked to be
385 picked, edited or reworded will have the trailer added.
386 +
387 See also INCOMPATIBLE OPTIONS below.
388
389 -i::
390 --interactive::
391 Make a list of the commits which are about to be rebased. Let the
392 user edit that list before rebasing. This mode can also be used to
393 split commits (see SPLITTING COMMITS below).
394 +
395 The commit list format can be changed by setting the configuration option
396 rebase.instructionFormat. A customized instruction format will automatically
397 have the long commit hash prepended to the format.
398 +
399 See also INCOMPATIBLE OPTIONS below.
400
401 -r::
402 --rebase-merges[=(rebase-cousins|no-rebase-cousins)]::
403 By default, a rebase will simply drop merge commits from the todo
404 list, and put the rebased commits into a single, linear branch.
405 With `--rebase-merges`, the rebase will instead try to preserve
406 the branching structure within the commits that are to be rebased,
407 by recreating the merge commits. Any resolved merge conflicts or
408 manual amendments in these merge commits will have to be
409 resolved/re-applied manually.
410 +
411 By default, or when `no-rebase-cousins` was specified, commits which do not
412 have `<upstream>` as direct ancestor will keep their original branch point,
413 i.e. commits that would be excluded by gitlink:git-log[1]'s
414 `--ancestry-path` option will keep their original ancestry by default. If
415 the `rebase-cousins` mode is turned on, such commits are instead rebased
416 onto `<upstream>` (or `<onto>`, if specified).
417 +
418 The `--rebase-merges` mode is similar in spirit to the deprecated
419 `--preserve-merges`, but in contrast to that option works well in interactive
420 rebases: commits can be reordered, inserted and dropped at will.
421 +
422 It is currently only possible to recreate the merge commits using the
423 `recursive` merge strategy; Different merge strategies can be used only via
424 explicit `exec git merge -s <strategy> [...]` commands.
425 +
426 See also REBASING MERGES and INCOMPATIBLE OPTIONS below.
427
428 -p::
429 --preserve-merges::
430 [DEPRECATED: use `--rebase-merges` instead] Recreate merge commits
431 instead of flattening the history by replaying commits a merge commit
432 introduces. Merge conflict resolutions or manual amendments to merge
433 commits are not preserved.
434 +
435 This uses the `--interactive` machinery internally, but combining it
436 with the `--interactive` option explicitly is generally not a good
437 idea unless you know what you are doing (see BUGS below).
438 +
439 See also INCOMPATIBLE OPTIONS below.
440
441 -x <cmd>::
442 --exec <cmd>::
443 Append "exec <cmd>" after each line creating a commit in the
444 final history. <cmd> will be interpreted as one or more shell
445 commands. Any command that fails will interrupt the rebase,
446 with exit code 1.
447 +
448 You may execute several commands by either using one instance of `--exec`
449 with several commands:
450 +
451 git rebase -i --exec "cmd1 && cmd2 && ..."
452 +
453 or by giving more than one `--exec`:
454 +
455 git rebase -i --exec "cmd1" --exec "cmd2" --exec ...
456 +
457 If `--autosquash` is used, "exec" lines will not be appended for
458 the intermediate commits, and will only appear at the end of each
459 squash/fixup series.
460 +
461 This uses the `--interactive` machinery internally, but it can be run
462 without an explicit `--interactive`.
463 +
464 See also INCOMPATIBLE OPTIONS below.
465
466 --root::
467 Rebase all commits reachable from <branch>, instead of
468 limiting them with an <upstream>. This allows you to rebase
469 the root commit(s) on a branch. When used with --onto, it
470 will skip changes already contained in <newbase> (instead of
471 <upstream>) whereas without --onto it will operate on every change.
472 When used together with both --onto and --preserve-merges,
473 'all' root commits will be rewritten to have <newbase> as parent
474 instead.
475 +
476 See also INCOMPATIBLE OPTIONS below.
477
478 --autosquash::
479 --no-autosquash::
480 When the commit log message begins with "squash! ..." (or
481 "fixup! ..."), and there is already a commit in the todo list that
482 matches the same `...`, automatically modify the todo list of rebase
483 -i so that the commit marked for squashing comes right after the
484 commit to be modified, and change the action of the moved commit
485 from `pick` to `squash` (or `fixup`). A commit matches the `...` if
486 the commit subject matches, or if the `...` refers to the commit's
487 hash. As a fall-back, partial matches of the commit subject work,
488 too. The recommended way to create fixup/squash commits is by using
489 the `--fixup`/`--squash` options of linkgit:git-commit[1].
490 +
491 If the `--autosquash` option is enabled by default using the
492 configuration variable `rebase.autoSquash`, this option can be
493 used to override and disable this setting.
494 +
495 See also INCOMPATIBLE OPTIONS below.
496
497 --autostash::
498 --no-autostash::
499 Automatically create a temporary stash entry before the operation
500 begins, and apply it after the operation ends. This means
501 that you can run rebase on a dirty worktree. However, use
502 with care: the final stash application after a successful
503 rebase might result in non-trivial conflicts.
504
505 --reschedule-failed-exec::
506 --no-reschedule-failed-exec::
507 Automatically reschedule `exec` commands that failed. This only makes
508 sense in interactive mode (or when an `--exec` option was provided).
509
510 INCOMPATIBLE OPTIONS
511 --------------------
512
513 The following options:
514
515 * --committer-date-is-author-date
516 * --ignore-date
517 * --whitespace
518 * --ignore-whitespace
519 * -C
520
521 are incompatible with the following options:
522
523 * --merge
524 * --strategy
525 * --strategy-option
526 * --allow-empty-message
527 * --[no-]autosquash
528 * --rebase-merges
529 * --preserve-merges
530 * --interactive
531 * --exec
532 * --keep-empty
533 * --edit-todo
534 * --root when used in combination with --onto
535
536 In addition, the following pairs of options are incompatible:
537
538 * --preserve-merges and --interactive
539 * --preserve-merges and --signoff
540 * --preserve-merges and --rebase-merges
541 * --rebase-merges and --strategy
542 * --rebase-merges and --strategy-option
543
544 BEHAVIORAL DIFFERENCES
545 -----------------------
546
547 There are some subtle differences how the backends behave.
548
549 Empty commits
550 ~~~~~~~~~~~~~
551
552 The am backend drops any "empty" commits, regardless of whether the
553 commit started empty (had no changes relative to its parent to
554 start with) or ended empty (all changes were already applied
555 upstream in other commits).
556
557 The interactive backend drops commits by default that
558 started empty and halts if it hits a commit that ended up empty.
559 The `--keep-empty` option exists for the interactive backend to allow
560 it to keep commits that started empty.
561
562 Directory rename detection
563 ~~~~~~~~~~~~~~~~~~~~~~~~~~
564
565 Directory rename heuristics are enabled in the merge and interactive
566 backends. Due to the lack of accurate tree information, directory
567 rename detection is disabled in the am backend.
568
569 include::merge-strategies.txt[]
570
571 NOTES
572 -----
573
574 You should understand the implications of using 'git rebase' on a
575 repository that you share. See also RECOVERING FROM UPSTREAM REBASE
576 below.
577
578 When the git-rebase command is run, it will first execute a "pre-rebase"
579 hook if one exists. You can use this hook to do sanity checks and
580 reject the rebase if it isn't appropriate. Please see the template
581 pre-rebase hook script for an example.
582
583 Upon completion, <branch> will be the current branch.
584
585 INTERACTIVE MODE
586 ----------------
587
588 Rebasing interactively means that you have a chance to edit the commits
589 which are rebased. You can reorder the commits, and you can
590 remove them (weeding out bad or otherwise unwanted patches).
591
592 The interactive mode is meant for this type of workflow:
593
594 1. have a wonderful idea
595 2. hack on the code
596 3. prepare a series for submission
597 4. submit
598
599 where point 2. consists of several instances of
600
601 a) regular use
602
603 1. finish something worthy of a commit
604 2. commit
605
606 b) independent fixup
607
608 1. realize that something does not work
609 2. fix that
610 3. commit it
611
612 Sometimes the thing fixed in b.2. cannot be amended to the not-quite
613 perfect commit it fixes, because that commit is buried deeply in a
614 patch series. That is exactly what interactive rebase is for: use it
615 after plenty of "a"s and "b"s, by rearranging and editing
616 commits, and squashing multiple commits into one.
617
618 Start it with the last commit you want to retain as-is:
619
620 git rebase -i <after-this-commit>
621
622 An editor will be fired up with all the commits in your current branch
623 (ignoring merge commits), which come after the given commit. You can
624 reorder the commits in this list to your heart's content, and you can
625 remove them. The list looks more or less like this:
626
627 -------------------------------------------
628 pick deadbee The oneline of this commit
629 pick fa1afe1 The oneline of the next commit
630 ...
631 -------------------------------------------
632
633 The oneline descriptions are purely for your pleasure; 'git rebase' will
634 not look at them but at the commit names ("deadbee" and "fa1afe1" in this
635 example), so do not delete or edit the names.
636
637 By replacing the command "pick" with the command "edit", you can tell
638 'git rebase' to stop after applying that commit, so that you can edit
639 the files and/or the commit message, amend the commit, and continue
640 rebasing.
641
642 To interrupt the rebase (just like an "edit" command would do, but without
643 cherry-picking any commit first), use the "break" command.
644
645 If you just want to edit the commit message for a commit, replace the
646 command "pick" with the command "reword".
647
648 To drop a commit, replace the command "pick" with "drop", or just
649 delete the matching line.
650
651 If you want to fold two or more commits into one, replace the command
652 "pick" for the second and subsequent commits with "squash" or "fixup".
653 If the commits had different authors, the folded commit will be
654 attributed to the author of the first commit. The suggested commit
655 message for the folded commit is the concatenation of the commit
656 messages of the first commit and of those with the "squash" command,
657 but omits the commit messages of commits with the "fixup" command.
658
659 'git rebase' will stop when "pick" has been replaced with "edit" or
660 when a command fails due to merge errors. When you are done editing
661 and/or resolving conflicts you can continue with `git rebase --continue`.
662
663 For example, if you want to reorder the last 5 commits, such that what
664 was HEAD~4 becomes the new HEAD. To achieve that, you would call
665 'git rebase' like this:
666
667 ----------------------
668 $ git rebase -i HEAD~5
669 ----------------------
670
671 And move the first patch to the end of the list.
672
673 You might want to recreate merge commits, e.g. if you have a history
674 like this:
675
676 ------------------
677 X
678 \
679 A---M---B
680 /
681 ---o---O---P---Q
682 ------------------
683
684 Suppose you want to rebase the side branch starting at "A" to "Q". Make
685 sure that the current HEAD is "B", and call
686
687 -----------------------------
688 $ git rebase -i -r --onto Q O
689 -----------------------------
690
691 Reordering and editing commits usually creates untested intermediate
692 steps. You may want to check that your history editing did not break
693 anything by running a test, or at least recompiling at intermediate
694 points in history by using the "exec" command (shortcut "x"). You may
695 do so by creating a todo list like this one:
696
697 -------------------------------------------
698 pick deadbee Implement feature XXX
699 fixup f1a5c00 Fix to feature XXX
700 exec make
701 pick c0ffeee The oneline of the next commit
702 edit deadbab The oneline of the commit after
703 exec cd subdir; make test
704 ...
705 -------------------------------------------
706
707 The interactive rebase will stop when a command fails (i.e. exits with
708 non-0 status) to give you an opportunity to fix the problem. You can
709 continue with `git rebase --continue`.
710
711 The "exec" command launches the command in a shell (the one specified
712 in `$SHELL`, or the default shell if `$SHELL` is not set), so you can
713 use shell features (like "cd", ">", ";" ...). The command is run from
714 the root of the working tree.
715
716 ----------------------------------
717 $ git rebase -i --exec "make test"
718 ----------------------------------
719
720 This command lets you check that intermediate commits are compilable.
721 The todo list becomes like that:
722
723 --------------------
724 pick 5928aea one
725 exec make test
726 pick 04d0fda two
727 exec make test
728 pick ba46169 three
729 exec make test
730 pick f4593f9 four
731 exec make test
732 --------------------
733
734 SPLITTING COMMITS
735 -----------------
736
737 In interactive mode, you can mark commits with the action "edit". However,
738 this does not necessarily mean that 'git rebase' expects the result of this
739 edit to be exactly one commit. Indeed, you can undo the commit, or you can
740 add other commits. This can be used to split a commit into two:
741
742 - Start an interactive rebase with `git rebase -i <commit>^`, where
743 <commit> is the commit you want to split. In fact, any commit range
744 will do, as long as it contains that commit.
745
746 - Mark the commit you want to split with the action "edit".
747
748 - When it comes to editing that commit, execute `git reset HEAD^`. The
749 effect is that the HEAD is rewound by one, and the index follows suit.
750 However, the working tree stays the same.
751
752 - Now add the changes to the index that you want to have in the first
753 commit. You can use `git add` (possibly interactively) or
754 'git gui' (or both) to do that.
755
756 - Commit the now-current index with whatever commit message is appropriate
757 now.
758
759 - Repeat the last two steps until your working tree is clean.
760
761 - Continue the rebase with `git rebase --continue`.
762
763 If you are not absolutely sure that the intermediate revisions are
764 consistent (they compile, pass the testsuite, etc.) you should use
765 'git stash' to stash away the not-yet-committed changes
766 after each commit, test, and amend the commit if fixes are necessary.
767
768
769 RECOVERING FROM UPSTREAM REBASE
770 -------------------------------
771
772 Rebasing (or any other form of rewriting) a branch that others have
773 based work on is a bad idea: anyone downstream of it is forced to
774 manually fix their history. This section explains how to do the fix
775 from the downstream's point of view. The real fix, however, would be
776 to avoid rebasing the upstream in the first place.
777
778 To illustrate, suppose you are in a situation where someone develops a
779 'subsystem' branch, and you are working on a 'topic' that is dependent
780 on this 'subsystem'. You might end up with a history like the
781 following:
782
783 ------------
784 o---o---o---o---o---o---o---o master
785 \
786 o---o---o---o---o subsystem
787 \
788 *---*---* topic
789 ------------
790
791 If 'subsystem' is rebased against 'master', the following happens:
792
793 ------------
794 o---o---o---o---o---o---o---o master
795 \ \
796 o---o---o---o---o o'--o'--o'--o'--o' subsystem
797 \
798 *---*---* topic
799 ------------
800
801 If you now continue development as usual, and eventually merge 'topic'
802 to 'subsystem', the commits from 'subsystem' will remain duplicated forever:
803
804 ------------
805 o---o---o---o---o---o---o---o master
806 \ \
807 o---o---o---o---o o'--o'--o'--o'--o'--M subsystem
808 \ /
809 *---*---*-..........-*--* topic
810 ------------
811
812 Such duplicates are generally frowned upon because they clutter up
813 history, making it harder to follow. To clean things up, you need to
814 transplant the commits on 'topic' to the new 'subsystem' tip, i.e.,
815 rebase 'topic'. This becomes a ripple effect: anyone downstream from
816 'topic' is forced to rebase too, and so on!
817
818 There are two kinds of fixes, discussed in the following subsections:
819
820 Easy case: The changes are literally the same.::
821
822 This happens if the 'subsystem' rebase was a simple rebase and
823 had no conflicts.
824
825 Hard case: The changes are not the same.::
826
827 This happens if the 'subsystem' rebase had conflicts, or used
828 `--interactive` to omit, edit, squash, or fixup commits; or
829 if the upstream used one of `commit --amend`, `reset`, or
830 `filter-branch`.
831
832
833 The easy case
834 ~~~~~~~~~~~~~
835
836 Only works if the changes (patch IDs based on the diff contents) on
837 'subsystem' are literally the same before and after the rebase
838 'subsystem' did.
839
840 In that case, the fix is easy because 'git rebase' knows to skip
841 changes that are already present in the new upstream. So if you say
842 (assuming you're on 'topic')
843 ------------
844 $ git rebase subsystem
845 ------------
846 you will end up with the fixed history
847 ------------
848 o---o---o---o---o---o---o---o master
849 \
850 o'--o'--o'--o'--o' subsystem
851 \
852 *---*---* topic
853 ------------
854
855
856 The hard case
857 ~~~~~~~~~~~~~
858
859 Things get more complicated if the 'subsystem' changes do not exactly
860 correspond to the ones before the rebase.
861
862 NOTE: While an "easy case recovery" sometimes appears to be successful
863 even in the hard case, it may have unintended consequences. For
864 example, a commit that was removed via `git rebase
865 --interactive` will be **resurrected**!
866
867 The idea is to manually tell 'git rebase' "where the old 'subsystem'
868 ended and your 'topic' began", that is, what the old merge-base
869 between them was. You will have to find a way to name the last commit
870 of the old 'subsystem', for example:
871
872 * With the 'subsystem' reflog: after 'git fetch', the old tip of
873 'subsystem' is at `subsystem@{1}`. Subsequent fetches will
874 increase the number. (See linkgit:git-reflog[1].)
875
876 * Relative to the tip of 'topic': knowing that your 'topic' has three
877 commits, the old tip of 'subsystem' must be `topic~3`.
878
879 You can then transplant the old `subsystem..topic` to the new tip by
880 saying (for the reflog case, and assuming you are on 'topic' already):
881 ------------
882 $ git rebase --onto subsystem subsystem@{1}
883 ------------
884
885 The ripple effect of a "hard case" recovery is especially bad:
886 'everyone' downstream from 'topic' will now have to perform a "hard
887 case" recovery too!
888
889 REBASING MERGES
890 ---------------
891
892 The interactive rebase command was originally designed to handle
893 individual patch series. As such, it makes sense to exclude merge
894 commits from the todo list, as the developer may have merged the
895 then-current `master` while working on the branch, only to rebase
896 all the commits onto `master` eventually (skipping the merge
897 commits).
898
899 However, there are legitimate reasons why a developer may want to
900 recreate merge commits: to keep the branch structure (or "commit
901 topology") when working on multiple, inter-related branches.
902
903 In the following example, the developer works on a topic branch that
904 refactors the way buttons are defined, and on another topic branch
905 that uses that refactoring to implement a "Report a bug" button. The
906 output of `git log --graph --format=%s -5` may look like this:
907
908 ------------
909 * Merge branch 'report-a-bug'
910 |\
911 | * Add the feedback button
912 * | Merge branch 'refactor-button'
913 |\ \
914 | |/
915 | * Use the Button class for all buttons
916 | * Extract a generic Button class from the DownloadButton one
917 ------------
918
919 The developer might want to rebase those commits to a newer `master`
920 while keeping the branch topology, for example when the first topic
921 branch is expected to be integrated into `master` much earlier than the
922 second one, say, to resolve merge conflicts with changes to the
923 DownloadButton class that made it into `master`.
924
925 This rebase can be performed using the `--rebase-merges` option.
926 It will generate a todo list looking like this:
927
928 ------------
929 label onto
930
931 # Branch: refactor-button
932 reset onto
933 pick 123456 Extract a generic Button class from the DownloadButton one
934 pick 654321 Use the Button class for all buttons
935 label refactor-button
936
937 # Branch: report-a-bug
938 reset refactor-button # Use the Button class for all buttons
939 pick abcdef Add the feedback button
940 label report-a-bug
941
942 reset onto
943 merge -C a1b2c3 refactor-button # Merge 'refactor-button'
944 merge -C 6f5e4d report-a-bug # Merge 'report-a-bug'
945 ------------
946
947 In contrast to a regular interactive rebase, there are `label`, `reset`
948 and `merge` commands in addition to `pick` ones.
949
950 The `label` command associates a label with the current HEAD when that
951 command is executed. These labels are created as worktree-local refs
952 (`refs/rewritten/<label>`) that will be deleted when the rebase
953 finishes. That way, rebase operations in multiple worktrees linked to
954 the same repository do not interfere with one another. If the `label`
955 command fails, it is rescheduled immediately, with a helpful message how
956 to proceed.
957
958 The `reset` command resets the HEAD, index and worktree to the specified
959 revision. It is similar to an `exec git reset --hard <label>`, but
960 refuses to overwrite untracked files. If the `reset` command fails, it is
961 rescheduled immediately, with a helpful message how to edit the todo list
962 (this typically happens when a `reset` command was inserted into the todo
963 list manually and contains a typo).
964
965 The `merge` command will merge the specified revision(s) into whatever
966 is HEAD at that time. With `-C <original-commit>`, the commit message of
967 the specified merge commit will be used. When the `-C` is changed to
968 a lower-case `-c`, the message will be opened in an editor after a
969 successful merge so that the user can edit the message.
970
971 If a `merge` command fails for any reason other than merge conflicts (i.e.
972 when the merge operation did not even start), it is rescheduled immediately.
973
974 At this time, the `merge` command will *always* use the `recursive`
975 merge strategy for regular merges, and `octopus` for octopus merges,
976 with no way to choose a different one. To work around
977 this, an `exec` command can be used to call `git merge` explicitly,
978 using the fact that the labels are worktree-local refs (the ref
979 `refs/rewritten/onto` would correspond to the label `onto`, for example).
980
981 Note: the first command (`label onto`) labels the revision onto which
982 the commits are rebased; The name `onto` is just a convention, as a nod
983 to the `--onto` option.
984
985 It is also possible to introduce completely new merge commits from scratch
986 by adding a command of the form `merge <merge-head>`. This form will
987 generate a tentative commit message and always open an editor to let the
988 user edit it. This can be useful e.g. when a topic branch turns out to
989 address more than a single concern and wants to be split into two or
990 even more topic branches. Consider this todo list:
991
992 ------------
993 pick 192837 Switch from GNU Makefiles to CMake
994 pick 5a6c7e Document the switch to CMake
995 pick 918273 Fix detection of OpenSSL in CMake
996 pick afbecd http: add support for TLS v1.3
997 pick fdbaec Fix detection of cURL in CMake on Windows
998 ------------
999
1000 The one commit in this list that is not related to CMake may very well
1001 have been motivated by working on fixing all those bugs introduced by
1002 switching to CMake, but it addresses a different concern. To split this
1003 branch into two topic branches, the todo list could be edited like this:
1004
1005 ------------
1006 label onto
1007
1008 pick afbecd http: add support for TLS v1.3
1009 label tlsv1.3
1010
1011 reset onto
1012 pick 192837 Switch from GNU Makefiles to CMake
1013 pick 918273 Fix detection of OpenSSL in CMake
1014 pick fdbaec Fix detection of cURL in CMake on Windows
1015 pick 5a6c7e Document the switch to CMake
1016 label cmake
1017
1018 reset onto
1019 merge tlsv1.3
1020 merge cmake
1021 ------------
1022
1023 BUGS
1024 ----
1025 The todo list presented by the deprecated `--preserve-merges --interactive`
1026 does not represent the topology of the revision graph (use `--rebase-merges`
1027 instead). Editing commits and rewording their commit messages should work
1028 fine, but attempts to reorder commits tend to produce counterintuitive results.
1029 Use `--rebase-merges` in such scenarios instead.
1030
1031 For example, an attempt to rearrange
1032 ------------
1033 1 --- 2 --- 3 --- 4 --- 5
1034 ------------
1035 to
1036 ------------
1037 1 --- 2 --- 4 --- 3 --- 5
1038 ------------
1039 by moving the "pick 4" line will result in the following history:
1040 ------------
1041 3
1042 /
1043 1 --- 2 --- 4 --- 5
1044 ------------
1045
1046 GIT
1047 ---
1048 Part of the linkgit:git[1] suite