git-rebase

GIT-REBASE(1)                     Git Manual                     GIT-REBASE(1)



NAME
       git-rebase - Forward-port local commits to the updated upstream head

SYNOPSIS
       git rebase [-i | --interactive] [options] [--onto ]
                []
       git rebase [-i | --interactive] [options] --onto 
               --root []


       git rebase --continue | --skip | --abort

DESCRIPTION
       If  is specified, git rebase will perform an automatic git
       checkout  before doing anything else. Otherwise it remains on
       the current branch.

       All changes made by commits in the current branch but that are not in
        are saved to a temporary area. This is the same set of
       commits that would be shown by git log ..HEAD (or git log
       HEAD, if --root is specified).

       The current branch is reset to , or  if the --onto
       option was supplied. This has the exact same effect as git reset --hard
        (or ). ORIG_HEAD is set to point at the tip of the
       branch before the reset.

       The commits that were previously saved into the temporary area are then
       reapplied to the current branch, one by one, in order. Note that any
       commits in HEAD which introduce the same textual changes as a commit in
       HEAD.. are omitted (i.e., a patch already accepted upstream
       with a different commit message or timestamp will be skipped).

       It is possible that a merge failure will prevent this process from
       being completely automatic. You will have to resolve any such merge
       failure and run git rebase --continue. Another option is to bypass the
       commit that caused the merge failure with git rebase --skip. To restore
       the original  and remove the .git/rebase-apply working files,
       use the command git rebase --abort instead.

       Assume the following history exists and the current branch is "topic":

                     A---B---C topic
                    /
               D---E---F---G master


       From this point, the result of either of the following commands:

           git rebase master
           git rebase master topic

       would be:

                             A'--B'--C' topic
                            /
               D---E---F---G master


       The latter form is just a short-hand of git checkout topic followed by
       git rebase master.

       If the upstream branch already contains a change you have made (e.g.,
       because you mailed a patch which was applied upstream), then that
       commit will be skipped. For example, running ‘git rebase master` on the
       following history (in which A’ and A introduce the same set of changes,
       but have different committer information):

                     A---B---C topic
                    /
               D---E---A'---F master


       will result in:

                              B'---C' topic
                             /
               D---E---A'---F master


       Here is how you would transplant a topic branch based on one branch to
       another, to pretend that you forked the topic branch from the latter
       branch, using rebase --onto.

       First let’s assume your topic is based on branch next. For example, a
       feature developed in topic depends on some functionality which is found
       in next.

               o---o---o---o---o  master
                    \
                     o---o---o---o---o  next
                                      \
                                       o---o---o  topic


       We want to make topic forked from branch master; for example, because
       the functionality on which topic depends was merged into the more
       stable master branch. We want our tree to look like this:

               o---o---o---o---o  master
                   |            \
                   |             o'--o'--o'  topic
                    \
                     o---o---o---o---o  next


       We can get this using the following command:

           git rebase --onto master next topic

       Another example of --onto option is to rebase part of a branch. If we
       have the following situation:

                                       H---I---J topicB
                                      /
                             E---F---G  topicA
                            /
               A---B---C---D  master


       then the command

           git rebase --onto master topicA topicB

       would result in:

                            H'--I'--J'  topicB
                           /
                           | E---F---G  topicA
                           |/
               A---B---C---D  master


       This is useful when topicB does not depend on topicA.

       A range of commits could also be removed with rebase. If we have the
       following situation:

               E---F---G---H---I---J  topicA


       then the command

           git rebase --onto topicA~5 topicA~3 topicA

       would result in the removal of commits F and G:

               E---H'---I'---J'  topicA


       This is useful if F and G were flawed in some way, or should not be
       part of topicA. Note that the argument to --onto and the 
       parameter can be any valid commit-ish.

       In case of conflict, git rebase will stop at the first problematic
       commit and leave conflict markers in the tree. You can use git diff to
       locate the markers (<<<<<<) and make edits to resolve the conflict. For
       each file you edit, you need to tell git that the conflict has been
       resolved, typically this would be done with

           git add 

       After resolving the conflict manually and updating the index with the
       desired resolution, you can continue the rebasing process with

           git rebase --continue

       Alternatively, you can undo the git rebase with

           git rebase --abort

CONFIGURATION
       rebase.stat
           Whether to show a diffstat of what changed upstream since the last
           rebase. False by default.

OPTIONS
       
           Starting point at which to create the new commits. If the --onto
           option is not specified, the starting point is . May be
           any valid commit, and not just an existing branch name.

       
           Upstream branch to compare against. May be any valid commit, not
           just an existing branch name.

       
           Working branch; defaults to HEAD.

       --continue
           Restart the rebasing process after having resolved a merge
           conflict.

       --abort
           Restore the original branch and abort the rebase operation.

       --skip
           Restart the rebasing process by skipping the current patch.

       -m, --merge
           Use merging strategies to rebase. When the recursive (default)
           merge strategy is used, this allows rebase to be aware of renames
           on the upstream side.

           Note that a rebase merge works by replaying each commit from the
           working branch on top of the  branch. Because of this,
           when a merge conflict happens, the side reported as ours is the
           so-far rebased series, starting with , and theirs is the
           working branch. In other words, the sides are swapped.

       -s , --strategy=
           Use the given merge strategy. If there is no -s option git
           merge-recursive is used instead. This implies --merge.

           Because git rebase replays each commit from the working branch on
           top of the  branch using the given strategy, using the
           ours strategy simply discards all patches from the , which
           makes little sense.

       -q, --quiet
           Be quiet. Implies --no-stat.

       -v, --verbose
           Be verbose. Implies --stat.

       --stat
           Show a diffstat of what changed upstream since the last rebase. The
           diffstat is also controlled by the configuration option
           rebase.stat.

       -n, --no-stat
           Do not show a diffstat as part of the rebase process.

       --no-verify
           This option bypasses the pre-rebase hook. See also githooks(5).

       -C
           Ensure at least  lines of surrounding context match before and
           after each change. When fewer lines of surrounding context exist
           they all must match. By default no context is ever ignored.

       -f, --force-rebase
           Force the rebase even if the current branch is a descendant of the
           commit you are rebasing onto. Normally the command will exit with
           the message "Current branch is up to date" in such a situation.

       --ignore-whitespace, --whitespace=
           These flag are passed to the git apply program (see git-apply(1))
           that applies the patch. Incompatible with the --interactive option.

       --committer-date-is-author-date, --ignore-date
           These flags are passed to git am to easily change the dates of the
           rebased commits (see git-am(1)).

       -i, --interactive
           Make a list of the commits which are about to be rebased. Let the
           user edit that list before rebasing. This mode can also be used to
           split commits (see SPLITTING COMMITS below).

       -p, --preserve-merges
           Instead of ignoring merges, try to recreate them.

       --root
           Rebase all commits reachable from , instead of limiting
           them with an . This allows you to rebase the root
           commit(s) on a branch. Must be used with --onto, and will skip
           changes already contained in  (instead of ).
           When used together with --preserve-merges, all root commits will be
           rewritten to have  as parent instead.

       --autosquash
           When the commit log message begins with "squash! ..." (or "fixup!
           ..."), and there is a commit whose title begins with the same ...,
           automatically modify the todo list of rebase -i so that the commit
           marked for squashing comes right after the commit to be modified,
           and change the action of the moved commit from pick to squash (or
           fixup).

           This option is only valid when --interactive option is used.

MERGE STRATEGIES
       The merge mechanism (git-merge and git-pull commands) allows the
       backend merge strategies to be chosen with -s option. Some strategies
       can also take their own options, which can be passed by giving
       -X arguments to git-merge and/or git-pull.

       resolve
           This can only resolve two heads (i.e. the current branch and
           another branch you pulled from) using a 3-way merge algorithm. It
           tries to carefully detect criss-cross merge ambiguities and is
           considered generally safe and fast.

       recursive
           This can only resolve two heads using a 3-way merge algorithm. When
           there is more than one common ancestor that can be used for 3-way
           merge, it creates a merged tree of the common ancestors and uses
           that as the reference tree for the 3-way merge. This has been
           reported to result in fewer merge conflicts without causing
           mis-merges by tests done on actual merge commits taken from Linux
           2.6 kernel development history. Additionally this can detect and
           handle merges involving renames. This is the default merge strategy
           when pulling or merging one branch.

           The recursive strategy can take the following options:

           ours
               This option forces conflicting hunks to be auto-resolved
               cleanly by favoring our version. Changes from the other tree
               that do not conflict with our side are reflected to the merge
               result.

               This should not be confused with the ours merge strategy, which
               does not even look at what the other tree contains at all. It
               discards everything the other tree did, declaring our history
               contains all that happened in it.

           theirs
               This is opposite of ours.

           subtree[=path]
               This option is a more advanced form of subtree strategy, where
               the strategy makes a guess on how two trees must be shifted to
               match with each other when merging. Instead, the specified path
               is prefixed (or stripped from the beginning) to make the shape
               of two trees to match.

       octopus
           This resolves cases with more than two heads, but refuses to do a
           complex merge that needs manual resolution. It is primarily meant
           to be used for bundling topic branch heads together. This is the
           default merge strategy when pulling or merging more than one
           branch.

       ours
           This resolves any number of heads, but the resulting tree of the
           merge is always that of the current branch head, effectively
           ignoring all changes from all other branches. It is meant to be
           used to supersede old development history of side branches. Note
           that this is different from the -Xours option to the recursive
           merge strategy.

       subtree
           This is a modified recursive strategy. When merging trees A and B,
           if B corresponds to a subtree of A, B is first adjusted to match
           the tree structure of A, instead of reading the trees at the same
           level. This adjustment is also done to the common ancestor tree.

NOTES
       You should understand the implications of using git rebase on a
       repository that you share. See also RECOVERING FROM UPSTREAM REBASE
       below.

       When the git-rebase command is run, it will first execute a
       "pre-rebase" hook if one exists. You can use this hook to do sanity
       checks and reject the rebase if it isn’t appropriate. Please see the
       template pre-rebase hook script for an example.

       Upon completion,  will be the current branch.

INTERACTIVE MODE
       Rebasing interactively means that you have a chance to edit the commits
       which are rebased. You can reorder the commits, and you can remove them
       (weeding out bad or otherwise unwanted patches).

       The interactive mode is meant for this type of workflow:

        1. have a wonderful idea

        2. hack on the code

        3. prepare a series for submission

        4. submit

       where point 2. consists of several instances of

        1. regular use

            1. finish something worthy of a commit

            2. commit

        2. independent fixup

            1. realize that something does not work

            2. fix that

            3. commit it

       Sometimes the thing fixed in b.2. cannot be amended to the not-quite
       perfect commit it fixes, because that commit is buried deeply in a
       patch series. That is exactly what interactive rebase is for: use it
       after plenty of "a"s and "b"s, by rearranging and editing commits, and
       squashing multiple commits into one.

       Start it with the last commit you want to retain as-is:

           git rebase -i 

       An editor will be fired up with all the commits in your current branch
       (ignoring merge commits), which come after the given commit. You can
       reorder the commits in this list to your heart’s content, and you can
       remove them. The list looks more or less like this:

           pick deadbee The oneline of this commit
           pick fa1afe1 The oneline of the next commit
           ...


       The oneline descriptions are purely for your pleasure; git rebase will
       not look at them but at the commit names ("deadbee" and "fa1afe1" in
       this example), so do not delete or edit the names.

       By replacing the command "pick" with the command "edit", you can tell
       git rebase to stop after applying that commit, so that you can edit the
       files and/or the commit message, amend the commit, and continue
       rebasing.

       If you just want to edit the commit message for a commit, replace the
       command "pick" with the command "reword".

       If you want to fold two or more commits into one, replace the command
       "pick" for the second and subsequent commits with "squash" or "fixup".
       If the commits had different authors, the folded commit will be
       attributed to the author of the first commit. The suggested commit
       message for the folded commit is the concatenation of the commit
       messages of the first commit and of those with the "squash" command,
       but omits the commit messages of commits with the "fixup" command.

       git rebase will stop when "pick" has been replaced with "edit" or when
       a command fails due to merge errors. When you are done editing and/or
       resolving conflicts you can continue with git rebase --continue.

       For example, if you want to reorder the last 5 commits, such that what
       was HEAD~4 becomes the new HEAD. To achieve that, you would call git
       rebase like this:

           $ git rebase -i HEAD~5


       And move the first patch to the end of the list.

       You might want to preserve merges, if you have a history like this:

                      X
                       \
                    A---M---B
                   /
           ---o---O---P---Q


       Suppose you want to rebase the side branch starting at "A" to "Q". Make
       sure that the current HEAD is "B", and call

           $ git rebase -i -p --onto Q O


SPLITTING COMMITS
       In interactive mode, you can mark commits with the action "edit".
       However, this does not necessarily mean that git rebase expects the
       result of this edit to be exactly one commit. Indeed, you can undo the
       commit, or you can add other commits. This can be used to split a
       commit into two:

       ·   Start an interactive rebase with git rebase -i ^, where
            is the commit you want to split. In fact, any commit range
           will do, as long as it contains that commit.

       ·   Mark the commit you want to split with the action "edit".

       ·   When it comes to editing that commit, execute git reset HEAD^. The
           effect is that the HEAD is rewound by one, and the index follows
           suit. However, the working tree stays the same.

       ·   Now add the changes to the index that you want to have in the first
           commit. You can use git add (possibly interactively) or git gui (or
           both) to do that.

       ·   Commit the now-current index with whatever commit message is
           appropriate now.

       ·   Repeat the last two steps until your working tree is clean.

       ·   Continue the rebase with git rebase --continue.

       If you are not absolutely sure that the intermediate revisions are
       consistent (they compile, pass the testsuite, etc.) you should use git
       stash to stash away the not-yet-committed changes after each commit,
       test, and amend the commit if fixes are necessary.

RECOVERING FROM UPSTREAM REBASE
       Rebasing (or any other form of rewriting) a branch that others have
       based work on is a bad idea: anyone downstream of it is forced to
       manually fix their history. This section explains how to do the fix
       from the downstream’s point of view. The real fix, however, would be to
       avoid rebasing the upstream in the first place.

       To illustrate, suppose you are in a situation where someone develops a
       subsystem branch, and you are working on a topic that is dependent on
       this subsystem. You might end up with a history like the following:

               o---o---o---o---o---o---o---o---o  master
                    \
                     o---o---o---o---o  subsystem
                                      \
                                       *---*---*  topic


       If subsystem is rebased against master, the following happens:

               o---o---o---o---o---o---o---o  master
                    \                       \
                     o---o---o---o---o       o'--o'--o'--o'--o'  subsystem
                                      \
                                       *---*---*  topic


       If you now continue development as usual, and eventually merge topic to
       subsystem, the commits from subsystem will remain duplicated forever:

               o---o---o---o---o---o---o---o  master
                    \                       \
                     o---o---o---o---o       o'--o'--o'--o'--o'--M  subsystem
                                      \                         /
                                       *---*---*-..........-*--*  topic


       Such duplicates are generally frowned upon because they clutter up
       history, making it harder to follow. To clean things up, you need to
       transplant the commits on topic to the new subsystem tip, i.e., rebase
       topic. This becomes a ripple effect: anyone downstream from topic is
       forced to rebase too, and so on!

       There are two kinds of fixes, discussed in the following subsections:

       Easy case: The changes are literally the same.
           This happens if the subsystem rebase was a simple rebase and had no
           conflicts.

       Hard case: The changes are not the same.
           This happens if the subsystem rebase had conflicts, or used
           --interactive to omit, edit, squash, or fixup commits; or if the
           upstream used one of commit --amend, reset, or filter-branch.

   The easy case
       Only works if the changes (patch IDs based on the diff contents) on
       subsystem are literally the same before and after the rebase subsystem
       did.

       In that case, the fix is easy because git rebase knows to skip changes
       that are already present in the new upstream. So if you say (assuming
       you’re on topic)

               $ git rebase subsystem


       you will end up with the fixed history

               o---o---o---o---o---o---o---o  master
                                            \
                                             o'--o'--o'--o'--o'  subsystem
                                                              \
                                                               *---*---*  topic


   The hard case
       Things get more complicated if the subsystem changes do not exactly
       correspond to the ones before the rebase.

           Note
           While an "easy case recovery" sometimes appears to be successful
           even in the hard case, it may have unintended consequences. For
           example, a commit that was removed via git rebase --interactive
           will be resurrected!

       The idea is to manually tell git rebase "where the old subsystem ended
       and your topic began", that is, what the old merge-base between them
       was. You will have to find a way to name the last commit of the old
       subsystem, for example:

       ·   With the subsystem reflog: after git fetch, the old tip of
           subsystem is at subsystem@{1}. Subsequent fetches will increase the
           number. (See git-reflog(1).)

       ·   Relative to the tip of topic: knowing that your topic has three
           commits, the old tip of subsystem must be topic~3.

       You can then transplant the old subsystem..topic to the new tip by
       saying (for the reflog case, and assuming you are on topic already):

               $ git rebase --onto subsystem subsystem@{1}


       The ripple effect of a "hard case" recovery is especially bad: everyone
       downstream from topic will now have to perform a "hard case" recovery
       too!

AUTHORS
       Written by Junio C Hamano  and Johannes E.
       Schindelin 

DOCUMENTATION
       Documentation by Junio C Hamano and the git-list
       .

GIT
       Part of the git(1) suite

NOTES
        1. gitster@pobox.com
           mailto:gitster@pobox.com

        2. johannes.schindelin@gmx.de
           mailto:johannes.schindelin@gmx.de

        3. git@vger.kernel.org
           mailto:git@vger.kernel.org



Git 1.7.0.4                       12/03/2010                     GIT-REBASE(1)