branch: force-copy a branch to itself via @{-1} is a no-op

[alt-git.git] / Documentation / git-worktree.txt

git-worktree(1)
===============

NAME
----
git-worktree - Manage multiple working trees


SYNOPSIS
--------
[verse]
'git worktree add' [-f] [--detach] [--checkout] [--lock [--reason <string>]]
                   [-b <new-branch>] <path> [<commit-ish>]
'git worktree list' [-v | --porcelain [-z]]
'git worktree lock' [--reason <string>] <worktree>
'git worktree move' <worktree> <new-path>
'git worktree prune' [-n] [-v] [--expire <expire>]
'git worktree remove' [-f] <worktree>
'git worktree repair' [<path>...]
'git worktree unlock' <worktree>

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

Manage multiple working trees attached to the same repository.

A git repository can support multiple working trees, allowing you to check
out more than one branch at a time.  With `git worktree add` a new working
tree is associated with the repository, along with additional metadata
that differentiates that working tree from others in the same repository.
The working tree, along with this metadata, is called a "worktree".

This new worktree is called a "linked worktree" as opposed to the "main
worktree" prepared by linkgit:git-init[1] or linkgit:git-clone[1].
A repository has one main worktree (if it's not a bare repository) and
zero or more linked worktrees. When you are done with a linked worktree,
remove it with `git worktree remove`.

In its simplest form, `git worktree add <path>` automatically creates a
new branch whose name is the final component of `<path>`, which is
convenient if you plan to work on a new topic. For instance, `git
worktree add ../hotfix` creates new branch `hotfix` and checks it out at
path `../hotfix`. To instead work on an existing branch in a new worktree,
use `git worktree add <path> <branch>`. On the other hand, if you just
plan to make some experimental changes or do testing without disturbing
existing development, it is often convenient to create a 'throwaway'
worktree not associated with any branch. For instance,
`git worktree add -d <path>` creates a new worktree with a detached `HEAD`
at the same commit as the current branch.

If a working tree is deleted without using `git worktree remove`, then
its associated administrative files, which reside in the repository
(see "DETAILS" below), will eventually be removed automatically (see
`gc.worktreePruneExpire` in linkgit:git-config[1]), or you can run
`git worktree prune` in the main or any linked worktree to clean up any
stale administrative files.

If the working tree for a linked worktree is stored on a portable device
or network share which is not always mounted, you can prevent its
administrative files from being pruned by issuing the `git worktree lock`
command, optionally specifying `--reason` to explain why the worktree is
locked.

COMMANDS
--------
add <path> [<commit-ish>]::

Create a worktree at `<path>` and checkout `<commit-ish>` into it. The new worktree
is linked to the current repository, sharing everything except per-worktree
files such as `HEAD`, `index`, etc. As a convenience, `<commit-ish>` may
be a bare "`-`", which is synonymous with `@{-1}`.
+
If `<commit-ish>` is a branch name (call it `<branch>`) and is not found,
and neither `-b` nor `-B` nor `--detach` are used, but there does
exist a tracking branch in exactly one remote (call it `<remote>`)
with a matching name, treat as equivalent to:
+
------------
$ git worktree add --track -b <branch> <path> <remote>/<branch>
------------
+
If the branch exists in multiple remotes and one of them is named by
the `checkout.defaultRemote` configuration variable, we'll use that
one for the purposes of disambiguation, even if the `<branch>` isn't
unique across all remotes. Set it to
e.g. `checkout.defaultRemote=origin` to always checkout remote
branches from there if `<branch>` is ambiguous but exists on the
`origin` remote. See also `checkout.defaultRemote` in
linkgit:git-config[1].
+
If `<commit-ish>` is omitted and neither `-b` nor `-B` nor `--detach` used,
then, as a convenience, the new worktree is associated with a branch (call
it `<branch>`) named after `$(basename <path>)`.  If `<branch>` doesn't
exist, a new branch based on `HEAD` is automatically created as if
`-b <branch>` was given.  If `<branch>` does exist, it will be checked out
in the new worktree, if it's not checked out anywhere else, otherwise the
command will refuse to create the worktree (unless `--force` is used).

list::

List details of each worktree.  The main worktree is listed first,
followed by each of the linked worktrees.  The output details include
whether the worktree is bare, the revision currently checked out, the
branch currently checked out (or "detached HEAD" if none), "locked" if
the worktree is locked, "prunable" if the worktree can be pruned by the
`prune` command.

lock::

If a worktree is on a portable device or network share which is not always
mounted, lock it to prevent its administrative files from being pruned
automatically. This also prevents it from being moved or deleted.
Optionally, specify a reason for the lock with `--reason`.

move::

Move a worktree to a new location. Note that the main worktree or linked
worktrees containing submodules cannot be moved with this command. (The
`git worktree repair` command, however, can reestablish the connection
with linked worktrees if you move the main worktree manually.)

prune::

Prune worktree information in `$GIT_DIR/worktrees`.

remove::

Remove a worktree. Only clean worktrees (no untracked files and no
modification in tracked files) can be removed. Unclean worktrees or ones
with submodules can be removed with `--force`. The main worktree cannot be
removed.

repair [<path>...]::

Repair worktree administrative files, if possible, if they have become
corrupted or outdated due to external factors.
+
For instance, if the main worktree (or bare repository) is moved, linked
worktrees will be unable to locate it. Running `repair` in the main
worktree will reestablish the connection from linked worktrees back to the
main worktree.
+
Similarly, if the working tree for a linked worktree is moved without
using `git worktree move`, the main worktree (or bare repository) will be
unable to locate it. Running `repair` within the recently-moved worktree
will reestablish the connection. If multiple linked worktrees are moved,
running `repair` from any worktree with each tree's new `<path>` as an
argument, will reestablish the connection to all the specified paths.
+
If both the main worktree and linked worktrees have been moved manually,
then running `repair` in the main worktree and specifying the new `<path>`
of each linked worktree will reestablish all connections in both
directions.

unlock::

Unlock a worktree, allowing it to be pruned, moved or deleted.

OPTIONS
-------

-f::
--force::
        By default, `add` refuses to create a new worktree when
        `<commit-ish>` is a branch name and is already checked out by
        another worktree, or if `<path>` is already assigned to some
        worktree but is missing (for instance, if `<path>` was deleted
        manually). This option overrides these safeguards. To add a missing but
        locked worktree path, specify `--force` twice.
+
`move` refuses to move a locked worktree unless `--force` is specified
twice. If the destination is already assigned to some other worktree but is
missing (for instance, if `<new-path>` was deleted manually), then `--force`
allows the move to proceed; use `--force` twice if the destination is locked.
+
`remove` refuses to remove an unclean worktree unless `--force` is used.
To remove a locked worktree, specify `--force` twice.

-b <new-branch>::
-B <new-branch>::
        With `add`, create a new branch named `<new-branch>` starting at
        `<commit-ish>`, and check out `<new-branch>` into the new worktree.
        If `<commit-ish>` is omitted, it defaults to `HEAD`.
        By default, `-b` refuses to create a new branch if it already
        exists. `-B` overrides this safeguard, resetting `<new-branch>` to
        `<commit-ish>`.

-d::
--detach::
        With `add`, detach `HEAD` in the new worktree. See "DETACHED HEAD"
        in linkgit:git-checkout[1].

--[no-]checkout::
        By default, `add` checks out `<commit-ish>`, however, `--no-checkout` can
        be used to suppress checkout in order to make customizations,
        such as configuring sparse-checkout. See "Sparse checkout"
        in linkgit:git-read-tree[1].

--[no-]guess-remote::
        With `worktree add <path>`, without `<commit-ish>`, instead
        of creating a new branch from `HEAD`, if there exists a tracking
        branch in exactly one remote matching the basename of `<path>`,
        base the new branch on the remote-tracking branch, and mark
        the remote-tracking branch as "upstream" from the new branch.
+
This can also be set up as the default behaviour by using the
`worktree.guessRemote` config option.

--[no-]track::
        When creating a new branch, if `<commit-ish>` is a branch,
        mark it as "upstream" from the new branch.  This is the
        default if `<commit-ish>` is a remote-tracking branch.  See
        `--track` in linkgit:git-branch[1] for details.

--lock::
        Keep the worktree locked after creation. This is the
        equivalent of `git worktree lock` after `git worktree add`,
        but without a race condition.

-n::
--dry-run::
        With `prune`, do not remove anything; just report what it would
        remove.

--porcelain::
        With `list`, output in an easy-to-parse format for scripts.
        This format will remain stable across Git versions and regardless of user
        configuration.  It is recommended to combine this with `-z`.
        See below for details.

-z::
        Terminate each line with a NUL rather than a newline when
        `--porcelain` is specified with `list`. This makes it possible
        to parse the output when a worktree path contains a newline
        character.

-q::
--quiet::
        With `add`, suppress feedback messages.

-v::
--verbose::
        With `prune`, report all removals.
+
With `list`, output additional information about worktrees (see below).

--expire <time>::
        With `prune`, only expire unused worktrees older than `<time>`.
+
With `list`, annotate missing worktrees as prunable if they are older than
`<time>`.

--reason <string>::
        With `lock` or with `add --lock`, an explanation why the worktree
        is locked.

<worktree>::
        Worktrees can be identified by path, either relative or absolute.
+
If the last path components in the worktree's path is unique among
worktrees, it can be used to identify a worktree. For example if you only
have two worktrees, at `/abc/def/ghi` and `/abc/def/ggg`, then `ghi` or
`def/ghi` is enough to point to the former worktree.

REFS
----
When using multiple worktrees, some refs are shared between all worktrees,
but others are specific to an individual worktree. One example is `HEAD`,
which is different for each worktree. This section is about the sharing
rules and how to access refs of one worktree from another.

In general, all pseudo refs are per-worktree and all refs starting with
`refs/` are shared. Pseudo refs are ones like `HEAD` which are directly
under `$GIT_DIR` instead of inside `$GIT_DIR/refs`. There are exceptions,
however: refs inside `refs/bisect` and `refs/worktree` are not shared.

Refs that are per-worktree can still be accessed from another worktree via
two special paths, `main-worktree` and `worktrees`. The former gives
access to per-worktree refs of the main worktree, while the latter to all
linked worktrees.

For example, `main-worktree/HEAD` or `main-worktree/refs/bisect/good`
resolve to the same value as the main worktree's `HEAD` and
`refs/bisect/good` respectively. Similarly, `worktrees/foo/HEAD` or
`worktrees/bar/refs/bisect/bad` are the same as
`$GIT_COMMON_DIR/worktrees/foo/HEAD` and
`$GIT_COMMON_DIR/worktrees/bar/refs/bisect/bad`.

To access refs, it's best not to look inside `$GIT_DIR` directly. Instead
use commands such as linkgit:git-rev-parse[1] or linkgit:git-update-ref[1]
which will handle refs correctly.

CONFIGURATION FILE
------------------
By default, the repository `config` file is shared across all worktrees.
If the config variables `core.bare` or `core.worktree` are present in the
common config file and `extensions.worktreeConfig` is disabled, then they
will be applied to the main worktree only.

In order to have worktree-specific configuration, you can turn on the
`worktreeConfig` extension, e.g.:

------------
$ git config extensions.worktreeConfig true
------------

In this mode, specific configuration stays in the path pointed by `git
rev-parse --git-path config.worktree`. You can add or update
configuration in this file with `git config --worktree`. Older Git
versions will refuse to access repositories with this extension.

Note that in this file, the exception for `core.bare` and `core.worktree`
is gone. If they exist in `$GIT_DIR/config`, you must move
them to the `config.worktree` of the main worktree. You may also take this
opportunity to review and move other configuration that you do not want to
share to all worktrees:

 - `core.worktree` should never be shared.

 - `core.bare` should not be shared if the value is `core.bare=true`.

 - `core.sparseCheckout` should not be shared, unless you are sure you
   always use sparse checkout for all worktrees.

See the documentation of `extensions.worktreeConfig` in
linkgit:git-config[1] for more details.

DETAILS
-------
Each linked worktree has a private sub-directory in the repository's
`$GIT_DIR/worktrees` directory.  The private sub-directory's name is usually
the base name of the linked worktree's path, possibly appended with a
number to make it unique.  For example, when `$GIT_DIR=/path/main/.git` the
command `git worktree add /path/other/test-next next` creates the linked
worktree in `/path/other/test-next` and also creates a
`$GIT_DIR/worktrees/test-next` directory (or `$GIT_DIR/worktrees/test-next1`
if `test-next` is already taken).

Within a linked worktree, `$GIT_DIR` is set to point to this private
directory (e.g. `/path/main/.git/worktrees/test-next` in the example) and
`$GIT_COMMON_DIR` is set to point back to the main worktree's `$GIT_DIR`
(e.g. `/path/main/.git`). These settings are made in a `.git` file located at
the top directory of the linked worktree.

Path resolution via `git rev-parse --git-path` uses either
`$GIT_DIR` or `$GIT_COMMON_DIR` depending on the path. For example, in the
linked worktree `git rev-parse --git-path HEAD` returns
`/path/main/.git/worktrees/test-next/HEAD` (not
`/path/other/test-next/.git/HEAD` or `/path/main/.git/HEAD`) while `git
rev-parse --git-path refs/heads/master` uses
`$GIT_COMMON_DIR` and returns `/path/main/.git/refs/heads/master`,
since refs are shared across all worktrees, except `refs/bisect` and
`refs/worktree`.

See linkgit:gitrepository-layout[5] for more information. The rule of
thumb is do not make any assumption about whether a path belongs to
`$GIT_DIR` or `$GIT_COMMON_DIR` when you need to directly access something
inside `$GIT_DIR`. Use `git rev-parse --git-path` to get the final path.

If you manually move a linked worktree, you need to update the `gitdir` file
in the entry's directory. For example, if a linked worktree is moved
to `/newpath/test-next` and its `.git` file points to
`/path/main/.git/worktrees/test-next`, then update
`/path/main/.git/worktrees/test-next/gitdir` to reference `/newpath/test-next`
instead. Better yet, run `git worktree repair` to reestablish the connection
automatically.

To prevent a `$GIT_DIR/worktrees` entry from being pruned (which
can be useful in some situations, such as when the
entry's worktree is stored on a portable device), use the
`git worktree lock` command, which adds a file named
`locked` to the entry's directory. The file contains the reason in
plain text. For example, if a linked worktree's `.git` file points
to `/path/main/.git/worktrees/test-next` then a file named
`/path/main/.git/worktrees/test-next/locked` will prevent the
`test-next` entry from being pruned.  See
linkgit:gitrepository-layout[5] for details.

When `extensions.worktreeConfig` is enabled, the config file
`.git/worktrees/<id>/config.worktree` is read after `.git/config` is.

LIST OUTPUT FORMAT
------------------
The `worktree list` command has two output formats. The default format shows the
details on a single line with columns.  For example:

------------
$ git worktree list
/path/to/bare-source            (bare)
/path/to/linked-worktree        abcd1234 [master]
/path/to/other-linked-worktree  1234abc  (detached HEAD)
------------

The command also shows annotations for each worktree, according to its state.
These annotations are:

 * `locked`, if the worktree is locked.
 * `prunable`, if the worktree can be pruned via `git worktree prune`.

------------
$ git worktree list
/path/to/linked-worktree    abcd1234 [master]
/path/to/locked-worktree    acbd5678 (brancha) locked
/path/to/prunable-worktree  5678abc  (detached HEAD) prunable
------------

For these annotations, a reason might also be available and this can be
seen using the verbose mode. The annotation is then moved to the next line
indented followed by the additional information.

------------
$ git worktree list --verbose
/path/to/linked-worktree              abcd1234 [master]
/path/to/locked-worktree-no-reason    abcd5678 (detached HEAD) locked
/path/to/locked-worktree-with-reason  1234abcd (brancha)
        locked: worktree path is mounted on a portable device
/path/to/prunable-worktree            5678abc1 (detached HEAD)
        prunable: gitdir file points to non-existent location
------------

Note that the annotation is moved to the next line if the additional
information is available, otherwise it stays on the same line as the
worktree itself.

Porcelain Format
~~~~~~~~~~~~~~~~
The porcelain format has a line per attribute.  If `-z` is given then the lines
are terminated with NUL rather than a newline.  Attributes are listed with a
label and value separated by a single space.  Boolean attributes (like `bare`
and `detached`) are listed as a label only, and are present only
if the value is true.  Some attributes (like `locked`) can be listed as a label
only or with a value depending upon whether a reason is available.  The first
attribute of a worktree is always `worktree`, an empty line indicates the
end of the record.  For example:

------------
$ git worktree list --porcelain
worktree /path/to/bare-source
bare

worktree /path/to/linked-worktree
HEAD abcd1234abcd1234abcd1234abcd1234abcd1234
branch refs/heads/master

worktree /path/to/other-linked-worktree
HEAD 1234abc1234abc1234abc1234abc1234abc1234a
detached

worktree /path/to/linked-worktree-locked-no-reason
HEAD 5678abc5678abc5678abc5678abc5678abc5678c
branch refs/heads/locked-no-reason
locked

worktree /path/to/linked-worktree-locked-with-reason
HEAD 3456def3456def3456def3456def3456def3456b
branch refs/heads/locked-with-reason
locked reason why is locked

worktree /path/to/linked-worktree-prunable
HEAD 1233def1234def1234def1234def1234def1234b
detached
prunable gitdir file points to non-existent location

------------

Unless `-z` is used any "unusual" characters in the lock reason such as newlines
are escaped and the entire reason is quoted as explained for the
configuration variable `core.quotePath` (see linkgit:git-config[1]).
For Example:

------------
$ git worktree list --porcelain
...
locked "reason\nwhy is locked"
...
------------

EXAMPLES
--------
You are in the middle of a refactoring session and your boss comes in and
demands that you fix something immediately. You might typically use
linkgit:git-stash[1] to store your changes away temporarily, however, your
working tree is in such a state of disarray (with new, moved, and removed
files, and other bits and pieces strewn around) that you don't want to risk
disturbing any of it. Instead, you create a temporary linked worktree to
make the emergency fix, remove it when done, and then resume your earlier
refactoring session.

------------
$ git worktree add -b emergency-fix ../temp master
$ pushd ../temp
# ... hack hack hack ...
$ git commit -a -m 'emergency fix for boss'
$ popd
$ git worktree remove ../temp
------------

BUGS
----
Multiple checkout in general is still experimental, and the support
for submodules is incomplete. It is NOT recommended to make multiple
checkouts of a superproject.

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