git-checkout
(1)
Name
git-checkout - Checkout a branch or paths to the working
tree
Synopsis
git checkout [-q] [-f] [-m] [<branch>]
git checkout [-q] [-f] [-m] [--detach] [<commit>]
git checkout [-q] [-f] [-m] [[-b|-B|--orphan] <new_branch>] [<start_point>]
git checkout [-f|--ours|--theirs|-m|--conflict=<style>] [<tree-ish>] [--] <paths>...
git checkout [-p|--patch] [<tree-ish>] [--] [<paths>...]
Description
Git Manual GIT-CHECKOUT(1)
NAME
git-checkout - Checkout a branch or paths to the working
tree
SYNOPSIS
git checkout [-q] [-f] [-m] [<branch>]
git checkout [-q] [-f] [-m] [--detach] [<commit>]
git checkout [-q] [-f] [-m] [[-b|-B|--orphan] <new_branch>] [<start_point>]
git checkout [-f|--ours|--theirs|-m|--conflict=<style>] [<tree-ish>] [--] <paths>...
git checkout [-p|--patch] [<tree-ish>] [--] [<paths>...]
DESCRIPTION
Updates files in the working tree to match the version in
the index or the specified tree. If no paths are given, git
checkout will also update HEAD to set the specified branch
as the current branch.
git checkout [<branch>], git checkout -b|-B <new_branch>
[<start point>], git checkout [--detach] [<commit>]
This form switches branches by updating the index,
working tree, and HEAD to reflect the specified branch
or commit.
If -b is given, a new branch is created as if git-
branch(1) were called and then checked out; in this case
you can use the --track or --no-track options, which
will be passed to git branch. As a convenience, --track
without -b implies branch creation; see the description
of --track below.
If -B is given, <new_branch> is created if it doesn't
exist; otherwise, it is reset. This is the transactional
equivalent of
$ git branch -f <branch> [<start point>]
$ git checkout <branch>
that is to say, the branch is not reset/created unless
"git checkout" is successful.
git checkout [-p|--patch] [<tree-ish>] [--] <pathspec>...
When <paths> or --patch are given, git checkout does not
switch branches. It updates the named paths in the
working tree from the index file or from a named
<tree-ish> (most often a commit). In this case, the -b
and --track options are meaningless and giving either of
them results in an error. The <tree-ish> argument can be
used to specify a specific tree-ish (i.e. commit, tag or
tree) to update the index for the given paths before
updating the working tree.
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The index may contain unmerged entries because of a
previous failed merge. By default, if you try to check
out such an entry from the index, the checkout operation
will fail and nothing will be checked out. Using -f will
ignore these unmerged entries. The contents from a
specific side of the merge can be checked out of the
index by using --ours or --theirs. With -m, changes made
to the working tree file can be discarded to re-create
the original conflicted merge result.
OPTIONS
-q, --quiet
Quiet, suppress feedback messages.
-f, --force
When switching branches, proceed even if the index or
the working tree differs from HEAD. This is used to
throw away local changes.
When checking out paths from the index, do not fail upon
unmerged entries; instead, unmerged entries are ignored.
--ours, --theirs
When checking out paths from the index, check out stage
#2 (ours) or #3 (theirs) for unmerged paths.
-b
Create a new branch named <new_branch> and start it at
<start_point>; see git-branch(1) for details.
-B
Creates the branch <new_branch> and start it at
<start_point>; if it already exists, then reset it to
<start_point>. This is equivalent to running "git
branch" with "-f"; see git-branch(1) for details.
-t, --track
When creating a new branch, set up "upstream"
configuration. See "--track" in git-branch(1) for
details.
If no -b option is given, the name of the new branch
will be derived from the remote-tracking branch. If
"remotes/" or "refs/remotes/" is prefixed it is stripped
away, and then the part up to the next slash (which
would be the nickname of the remote) is removed. This
would tell us to use "hack" as the local branch when
branching off of "origin/hack" (or
"remotes/origin/hack", or even
"refs/remotes/origin/hack"). If the given name has no
slash, or the above guessing results in an empty name,
the guessing is aborted. You can explicitly give a name
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with -b in such a case.
--no-track
Do not set up "upstream" configuration, even if the
branch.autosetupmerge configuration variable is true.
-l
Create the new branch's reflog; see git-branch(1) for
details.
--detach
Rather than checking out a branch to work on it, check
out a commit for inspection and discardable experiments.
This is the default behavior of "git checkout <commit>"
when <commit> is not a branch name. See the "DETACHED
HEAD" section below for details.
--orphan
Create a new orphan branch, named <new_branch>, started
from <start_point> and switch to it. The first commit
made on this new branch will have no parents and it will
be the root of a new history totally disconnected from
all the other branches and commits.
The index and the working tree are adjusted as if you
had previously run "git checkout <start_point>". This
allows you to start a new history that records a set of
paths similar to <start_point> by easily running "git
commit -a" to make the root commit.
This can be useful when you want to publish the tree
from a commit without exposing its full history. You
might want to do this to publish an open source branch
of a project whose current tree is "clean", but whose
full history contains proprietary or otherwise
encumbered bits of code.
If you want to start a disconnected history that records
a set of paths that is totally different from the one of
<start_point>, then you should clear the index and the
working tree right after creating the orphan branch by
running "git rm -rf ." from the top level of the working
tree. Afterwards you will be ready to prepare your new
files, repopulating the working tree, by copying them
from elsewhere, extracting a tarball, etc.
-m, --merge
When switching branches, if you have local modifications
to one or more files that are different between the
current branch and the branch to which you are
switching, the command refuses to switch branches in
order to preserve your modifications in context.
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However, with this option, a three-way merge between the
current branch, your working tree contents, and the new
branch is done, and you will be on the new branch.
When a merge conflict happens, the index entries for
conflicting paths are left unmerged, and you need to
resolve the conflicts and mark the resolved paths with
git add (or git rm if the merge should result in
deletion of the path).
When checking out paths from the index, this option lets
you recreate the conflicted merge in the specified
paths.
--conflict=<style>
The same as --merge option above, but changes the way
the conflicting hunks are presented, overriding the
merge.conflictstyle configuration variable. Possible
values are "merge" (default) and "diff3" (in addition to
what is shown by "merge" style, shows the original
contents).
-p, --patch
Interactively select hunks in the difference between the
<tree-ish> (or the index, if unspecified) and the
working tree. The chosen hunks are then applied in
reverse to the working tree (and if a <tree-ish> was
specified, the index).
This means that you can use git checkout -p to
selectively discard edits from your current working
tree. See the "Interactive Mode" section of git-add(1)
to learn how to operate the --patch mode.
<branch>
Branch to checkout; if it refers to a branch (i.e., a
name that, when prepended with "refs/heads/", is a valid
ref), then that branch is checked out. Otherwise, if it
refers to a valid commit, your HEAD becomes "detached"
and you are no longer on any branch (see below for
details).
As a special case, the "@{-N}" syntax for the N-th last
branch checks out the branch (instead of detaching). You
may also specify - which is synonymous with "@{-1}".
As a further special case, you may use "A...B" as a
shortcut for the merge base of A and B if there is
exactly one merge base. You can leave out at most one of
A and B, in which case it defaults to HEAD.
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<new_branch>
Name for the new branch.
<start_point>
The name of a commit at which to start the new branch;
see git-branch(1) for details. Defaults to HEAD.
<tree-ish>
Tree to checkout from (when paths are given). If not
specified, the index will be used.
DETACHED HEAD
HEAD normally refers to a named branch (e.g. master).
Meanwhile, each branch refers to a specific commit. Let's
look at a repo with three commits, one of them tagged, and
with branch master checked out:
HEAD (refers to branch 'master')
|
v
a---b---c branch 'master' (refers to commit 'c')
^
|
tag 'v2.0' (refers to commit 'b')
When a commit is created in this state, the branch is
updated to refer to the new commit. Specifically, git commit
creates a new commit d, whose parent is commit c, and then
updates branch master to refer to new commit d. HEAD still
refers to branch master and so indirectly now refers to
commit d:
$ edit; git add; git commit
HEAD (refers to branch 'master')
|
v
a---b---c---d branch 'master' (refers to commit 'd')
^
|
tag 'v2.0' (refers to commit 'b')
It is sometimes useful to be able to checkout a commit that
is not at the tip of any named branch, or even to create a
new commit that is not referenced by a named branch. Let's
look at what happens when we checkout commit b (here we show
two ways this may be done):
$ git checkout v2.0 # or
$ git checkout master^^
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HEAD (refers to commit 'b')
|
v
a---b---c---d branch 'master' (refers to commit 'd')
^
|
tag 'v2.0' (refers to commit 'b')
Notice that regardless of which checkout command we use,
HEAD now refers directly to commit b. This is known as being
in detached HEAD state. It means simply that HEAD refers to
a specific commit, as opposed to referring to a named
branch. Let's see what happens when we create a commit:
$ edit; git add; git commit
HEAD (refers to commit 'e')
|
v
e
/
a---b---c---d branch 'master' (refers to commit 'd')
^
|
tag 'v2.0' (refers to commit 'b')
There is now a new commit e, but it is referenced only by
HEAD. We can of course add yet another commit in this state:
$ edit; git add; git commit
HEAD (refers to commit 'f')
|
v
e---f
/
a---b---c---d branch 'master' (refers to commit 'd')
^
|
tag 'v2.0' (refers to commit 'b')
In fact, we can perform all the normal git operations. But,
let's look at what happens when we then checkout master:
$ git checkout master
HEAD (refers to branch 'master')
e---f |
/ v
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a---b---c---d branch 'master' (refers to commit 'd')
^
|
tag 'v2.0' (refers to commit 'b')
It is important to realize that at this point nothing refers
to commit f. Eventually commit f (and by extension commit e)
will be deleted by the routine git garbage collection
process, unless we create a reference before that happens.
If we have not yet moved away from commit f, any of these
will create a reference to it:
$ git checkout -b foo (1)
$ git branch foo (2)
$ git tag foo (3)
1. creates a new branch foo, which refers to commit f, and
then updates HEAD to refer to branch foo. In other words,
we'll no longer be in detached HEAD state after this
command.
2. similarly creates a new branch foo, which refers to
commit f, but leaves HEAD detached.
3. creates a new tag foo, which refers to commit f, leaving
HEAD detached.
If we have moved away from commit f, then we must first
recover its object name (typically by using git reflog), and
then we can create a reference to it. For example, to see
the last two commits to which HEAD referred, we can use
either of these commands:
$ git reflog -2 HEAD # or
$ git log -g -2 HEAD
EXAMPLES
1. The following sequence checks out the master branch,
reverts the Makefile to two revisions back, deletes
hello.c by mistake, and gets it back from the index.
$ git checkout master (1)
$ git checkout master~2 Makefile (2)
$ rm -f hello.c
$ git checkout hello.c (3)
1. switch branch
2. take a file out of another commit
3. restore hello.c from the index
If you have an unfortunate branch that is named hello.c,
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this step would be confused as an instruction to switch
to that branch. You should instead write:
$ git checkout -- hello.c
2. After working in the wrong branch, switching to the
correct branch would be done using:
$ git checkout mytopic
However, your "wrong" branch and correct "mytopic"
branch may differ in files that you have modified
locally, in which case the above checkout would fail
like this:
$ git checkout mytopic
error: You have local changes to 'frotz'; not switching branches.
You can give the -m flag to the command, which would try
a three-way merge:
$ git checkout -m mytopic
Auto-merging frotz
After this three-way merge, the local modifications are
not registered in your index file, so git diff would
show you what changes you made since the tip of the new
branch.
3. When a merge conflict happens during switching branches
with the -m option, you would see something like this:
$ git checkout -m mytopic
Auto-merging frotz
ERROR: Merge conflict in frotz
fatal: merge program failed
At this point, git diff shows the changes cleanly merged
as in the previous example, as well as the changes in
the conflicted files. Edit and resolve the conflict and
mark it resolved with git add as usual:
$ edit frotz
$ git add frotz
GIT
Part of the git(1) suite
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ATTRIBUTES
See attributes(5) for descriptions of the following
attributes:
+---------------+--------------------------+
|ATTRIBUTE TYPE | ATTRIBUTE VALUE |
+---------------+--------------------------+
|Availability | developer/versioning/git |
+---------------+--------------------------+
|Stability | Uncommitted |
+---------------+--------------------------+
NOTES
This software was built from source available at
https://java.net/projects/solaris-userland. The original
community source was downloaded from http://git-
core.googlecode.com/files/git-1.7.9.2.tar.gz
Further information about this software can be found on the
open source community website at http://git-scm.com/.
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