Documentation: clarify branch creation

[thirdparty/git.git] / Documentation / git-branch.txt

git-branch(1)
=============

NAME
----
git-branch - List, create, or delete branches

SYNOPSIS
--------
[verse]
'git branch' [--color | --no-color] [-r | -a]
	[-v [--abbrev=<length> | --no-abbrev]]
	[(--merged | --no-merged | --contains) [<commit>]]
'git branch' [--track | --no-track] [-l] [-f] <branchname> [<start-point>]
'git branch' (-m | -M) [<oldbranch>] <newbranch>
'git branch' (-d | -D) [-r] <branchname>...

DESCRIPTION
-----------

With no arguments, existing branches are listed and the current branch will
be highlighted with an asterisk.  Option `-r` causes the remote-tracking
branches to be listed, and option `-a` shows both.

With `--contains`, shows only the branches that contain the named commit
(in other words, the branches whose tip commits are descendants of the
named commit).  With `--merged`, only branches merged into the named
commit (i.e. the branches whose tip commits are reachable from the named
commit) will be listed.  With `--no-merged` only branches not merged into
the named commit will be listed.  If the <commit> argument is missing it
defaults to 'HEAD' (i.e. the tip of the current branch).

The command's second form creates a new branch head named <branchname>
which points to the current 'HEAD', or <start-point> if given.

Note that this will create the new branch, but it will not switch the
working tree to it; use "git checkout <newbranch>" to switch to the
new branch.

When a local branch is started off a remote branch, git sets up the
branch so that 'git-pull' will appropriately merge from
the remote branch. This behavior may be changed via the global
`branch.autosetupmerge` configuration flag. That setting can be
overridden by using the `--track` and `--no-track` options.

With a '-m' or '-M' option, <oldbranch> will be renamed to <newbranch>.
If <oldbranch> had a corresponding reflog, it is renamed to match
<newbranch>, and a reflog entry is created to remember the branch
renaming. If <newbranch> exists, -M must be used to force the rename
to happen.

With a `-d` or `-D` option, `<branchname>` will be deleted.  You may
specify more than one branch for deletion.  If the branch currently
has a reflog then the reflog will also be deleted.

Use -r together with -d to delete remote-tracking branches. Note, that it
only makes sense to delete remote-tracking branches if they no longer exist
in the remote repository or if 'git-fetch' was configured not to fetch
them again. See also the 'prune' subcommand of linkgit:git-remote[1] for a
way to clean up all obsolete remote-tracking branches.


OPTIONS
-------
-d::
	Delete a branch. The branch must be fully merged in HEAD.

-D::
	Delete a branch irrespective of its merged status.

-l::
	Create the branch's reflog.  This activates recording of
	all changes made to the branch ref, enabling use of date
	based sha1 expressions such as "<branchname>@\{yesterday}".

-f::
--force::
	Reset <branchname> to <startpoint> if <branchname> exists
	already. Without `-f` 'git-branch' refuses to change an existing branch.

-m::
	Move/rename a branch and the corresponding reflog.

-M::
	Move/rename a branch even if the new branch name already exists.

--color::
	Color branches to highlight current, local, and remote branches.

--no-color::
	Turn off branch colors, even when the configuration file gives the
	default to color output.

-r::
	List or delete (if used with -d) the remote-tracking branches.

-a::
	List both remote-tracking branches and local branches.

-v::
--verbose::
	Show sha1 and commit subject line for each head, along with
	relationship to upstream branch (if any). If given twice, print
	the name of the upstream branch, as well.

--abbrev=<length>::
	Alter the sha1's minimum display length in the output listing.
	The default value is 7.

--no-abbrev::
	Display the full sha1s in the output listing rather than abbreviating them.

-t::
--track::
	When creating a new branch, set up configuration to mark the
	start-point branch as "upstream" from the new branch. This
	configuration will tell git to show the relationship between the
	two branches in `git status` and `git branch -v`. Furthermore,
	it directs `git pull` without arguments to pull from the
	upstream when the new branch is checked out.
+
This behavior is the default when the start point is a remote branch.
Set the branch.autosetupmerge configuration variable to `false` if you
want `git checkout` and `git branch` to always behave as if '--no-track'
were given. Set it to `always` if you want this behavior when the
start-point is either a local or remote branch.

--no-track::
	Do not set up "upstream" configuration, even if the
	branch.autosetupmerge configuration variable is true.

--contains <commit>::
	Only list branches which contain the specified commit.

--merged [<commit>]::
	Only list branches whose tips are reachable from the
	specified commit (HEAD if not specified).

--no-merged [<commit>]::
	Only list branches whose tips are not reachable from the
	specified commit (HEAD if not specified).

<branchname>::
	The name of the branch to create or delete.
	The new branch name must pass all checks defined by
	linkgit:git-check-ref-format[1].  Some of these checks
	may restrict the characters allowed in a branch name.

<start-point>::
	The new branch head will point to this commit.  It may be
	given as a branch name, a commit-id, or a tag.  If this
	option is omitted, the current HEAD will be used instead.

<oldbranch>::
	The name of an existing branch to rename.

<newbranch>::
	The new name for an existing branch. The same restrictions as for
	<branchname> apply.


Examples
--------

Start development from a known tag::
+
------------
$ git clone git://git.kernel.org/pub/scm/.../linux-2.6 my2.6
$ cd my2.6
$ git branch my2.6.14 v2.6.14   <1>
$ git checkout my2.6.14
------------
+
<1> This step and the next one could be combined into a single step with
"checkout -b my2.6.14 v2.6.14".

Delete an unneeded branch::
+
------------
$ git clone git://git.kernel.org/.../git.git my.git
$ cd my.git
$ git branch -d -r origin/todo origin/html origin/man   <1>
$ git branch -D test                                    <2>
------------
+
<1> Delete the remote-tracking branches "todo", "html" and "man". The next
'fetch' or 'pull' will create them again unless you configure them not to.
See linkgit:git-fetch[1].
<2> Delete the "test" branch even if the "master" branch (or whichever branch
is currently checked out) does not have all commits from the test branch.


Notes
-----

If you are creating a branch that you want to checkout immediately, it is
easier to use the git checkout command with its `-b` option to create
a branch and check it out with a single command.

The options `--contains`, `--merged` and `--no-merged` serve three related
but different purposes:

- `--contains <commit>` is used to find all branches which will need
  special attention if <commit> were to be rebased or amended, since those
  branches contain the specified <commit>.

- `--merged` is used to find all branches which can be safely deleted,
  since those branches are fully contained by HEAD.

- `--no-merged` is used to find branches which are candidates for merging
  into HEAD, since those branches are not fully contained by HEAD.

SEE ALSO
--------
linkgit:git-check-ref-format[1],
linkgit:git-fetch[1],
linkgit:git-remote[1],
link:user-manual.html#what-is-a-branch[``Understanding history: What is
a branch?''] in the Git User's Manual.

Author
------
Written by Linus Torvalds <torvalds@osdl.org> and Junio C Hamano <gitster@pobox.com>

Documentation
--------------
Documentation by Junio C Hamano and the git-list <git@vger.kernel.org>.

GIT
---
Part of the linkgit:git[1] suite