git-checkout

Langue: en

Version: 09/30/2010 (fedora - 01/12/10)

Section: 1 (Commandes utilisateur)

NAME

git-checkout - Checkout a branch or paths to the working tree

SYNOPSIS

 git checkout [-q] [-f] [-m] [<branch>]
 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 --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>]

This form switches branches by updating the index, working tree, and HEAD to reflect the specified branch.
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 doesncqt 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 [--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.
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 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 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 branchcqs reflog; see git-branch(1) 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. 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.

<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.

<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

It is sometimes useful to be able to checkout a commit that is not at the tip of one of your branches. The most obvious example is to check out the commit at a tagged official release point, like this:

 $ git checkout v2.6.18
 

Earlier versions of git did not allow this and asked you to create a temporary branch using the -b option, but starting from version 1.5.0, the above command detaches your HEAD from the current branch and directly points at the commit named by the tag (v2.6.18 in the example above).

You can use all git commands while in this state. You can use git reset --hard $othercommit to further move around, for example. You can make changes and create a new commit on top of a detached HEAD. You can even create a merge by using git merge $othercommit.

The state you are in while your HEAD is detached is not recorded by any branch (which is natural --- you are not on any branch). What this means is that you can discard your temporary commits and merges by switching back to an existing branch (e.g. git checkout master), and a later git prune or git gc would garbage-collect them. If you did this by mistake, you can ask the reflog for HEAD where you were, e.g.

 $ 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, 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
 

AUTHOR

Written by Linus Torvalds <m[blue]torvalds@osdl.orgm[][1]>

DOCUMENTATION

Documentation by Junio C Hamano and the git-list <m[blue]git@vger.kernel.orgm[][2]>.

GIT

Part of the git(1) suite

NOTES

1.
torvalds@osdl.org
mailto:torvalds@osdl.org
2.
git@vger.kernel.org
mailto:git@vger.kernel.org