--------
[verse]
'git checkout' [-q] [-f] [-m] [<branch>]
-'git checkout' [-q] [-f] [-m] [-b <new_branch>] [<start_point>]
+'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>...]
branch.
'git checkout' [<branch>]::
-'git checkout' -b <new branch> [<start point>]::
+'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.
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' [--patch] [<tree-ish>] [--] <pathspec>...::
- When <paths> or `--patch` are given, 'git checkout' *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.
+ 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
Create a new branch named <new_branch> and start it at
<start_point>; see linkgit: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
+ linkgit:git-branch[1] for details.
+
-t::
--track::
When creating a new branch, set up "upstream" configuration. See
"--track" in linkgit: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/"
+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
Create the new branch's reflog; see linkgit: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,
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
+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`.