also update `HEAD` to set the specified branch as the current
branch.
-'git checkout' [<branch>]::
+'git checkout' <branch>::
+ To prepare for working on <branch>, switch to it by updating
+ the index and the files in the working tree, and by pointing
+ HEAD at the branch. Local modifications to the files in the
+ working tree are kept, so that they can be committed to the
+ <branch>.
++
+If <branch> is not found but there does exist a tracking branch in
+exactly one remote (call it <remote>) with a matching name, treat as
+equivalent to
++
+------------
+$ git checkout -b <branch> --track <remote>/<branch>
+------------
++
+You could omit <branch>, in which case the command degenerates to
+"check out the current branch", which is a glorified no-op with a
+rather expensive side-effects to show only the tracking information,
+if exists, for the current 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 linkgit: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.
+ Specifying `-b` causes a new branch to be created as if
+ linkgit: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
that is to say, the branch is not reset/created unless "git checkout" is
successful.
+'git checkout' --detach [<branch>]::
+'git checkout' <commit>::
+
+ Prepare to work on top of <commit>, by detaching HEAD at it
+ (see "DETACHED HEAD" section), and updating the index and the
+ files in the working tree. Local modifications to the files
+ in the working tree are kept, so that the resulting working
+ tree will be the state recorded in the commit plus the local
+ modifications.
++
+Passing `--detach` forces this behavior in the case of a <branch> (without
+the option, giving a branch name to the command would check out the branch,
+instead of detaching HEAD at it), or the current commit,
+if no <branch> is specified.
+
'git checkout' [-p|--patch] [<tree-ish>] [--] <pathspec>...::
When <paths> or `--patch` are given, 'git checkout' does *not*
When checking out paths from the index, check out stage #2
('ours') or #3 ('theirs') for unmerged paths.
--b::
+-b <new_branch>::
Create a new branch named <new_branch> and start it at
<start_point>; see linkgit:git-branch[1] for details.
--B::
+-B <new_branch>::
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
<commit> is not a branch name. See the "DETACHED HEAD" section
below for details.
---orphan::
+--orphan <new_branch>::
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