GIT-SPARSE-CHECKOU(1) Git Manual GIT-SPARSE-CHECKOU(1)
NAME
git-sparse-checkout - Reduce your working tree to a subset of tracked
files
SYNOPSIS
git sparse-checkout (init | list | set | add | reapply | disable) [<options>]
DESCRIPTION
This command is used to create sparse checkouts, which change the
working tree from having all tracked files present to only having a
subset of those files. It can also switch which subset of files are
present, or undo and go back to having all tracked files present in the
working copy.
The subset of files is chosen by providing a list of directories in
cone mode (the default), or by providing a list of patterns in non-cone
mode.
When in a sparse-checkout, other Git commands behave a bit differently.
For example, switching branches will not update paths outside the
sparse-checkout directories/patterns, and git commit -a will not record
paths outside the sparse-checkout directories/patterns as deleted.
THIS COMMAND IS EXPERIMENTAL. ITS BEHAVIOR, AND THE BEHAVIOR OF OTHER
COMMANDS IN THE PRESENCE OF SPARSE-CHECKOUTS, WILL LIKELY CHANGE IN THE
FUTURE.
COMMANDS
list
Describe the directories or patterns in the sparse-checkout file.
set
Enable the necessary sparse-checkout config settings
(core.sparseCheckout, core.sparseCheckoutCone, and index.sparse) if
they are not already set to the desired values, populate the
sparse-checkout file from the list of arguments following the set
subcommand, and update the working directory to match.
To ensure that adjusting the sparse-checkout settings within a
worktree does not alter the sparse-checkout settings in other
worktrees, the set subcommand will upgrade your repository config
to use worktree-specific config if not already present. The
sparsity defined by the arguments to the set subcommand are stored
in the worktree-specific sparse-checkout file. See git-worktree(1)
and the documentation of extensions.worktreeConfig in git-config(1)
for more details.
When the --stdin option is provided, the directories or patterns
are read from standard in as a newline-delimited list instead of
from the arguments.
By default, the input list is considered a list of directories,
matching the output of git ls-tree -d --name-only. This includes
interpreting pathnames that begin with a double quote (") as
C-style quoted strings. Note that all files under the specified
directories (at any depth) will be included in the sparse checkout,
as well as files that are siblings of either the given directory or
any of its ancestors (see CONE PATTERN SET below for more details).
In the past, this was not the default, and --cone needed to be
specified or core.sparseCheckoutCone needed to be enabled.
When --no-cone is passed, the input list is considered a list of
patterns. This mode has a number of drawbacks, including not
working with some options like --sparse-index. As explained in the
"Non-cone Problems" section below, we do not recommend using it.
Use the --[no-]sparse-index option to use a sparse index (the
default is to not use it). A sparse index reduces the size of the
index to be more closely aligned with your sparse-checkout
definition. This can have significant performance advantages for
commands such as git status or git add. This feature is still
experimental. Some commands might be slower with a sparse index
until they are properly integrated with the feature.
WARNING: Using a sparse index requires modifying the index in a way
that is not completely understood by external tools. If you have
trouble with this compatibility, then run git sparse-checkout init
--no-sparse-index to rewrite your index to not be sparse. Older
versions of Git will not understand the sparse directory entries
index extension and may fail to interact with your repository until
it is disabled.
add
Update the sparse-checkout file to include additional directories
(in cone mode) or patterns (in non-cone mode). By default, these
directories or patterns are read from the command-line arguments,
but they can be read from stdin using the --stdin option.
reapply
Reapply the sparsity pattern rules to paths in the working tree.
Commands like merge or rebase can materialize paths to do their
work (e.g. in order to show you a conflict), and other
sparse-checkout commands might fail to sparsify an individual file
(e.g. because it has unstaged changes or conflicts). In such cases,
it can make sense to run git sparse-checkout reapply later after
cleaning up affected paths (e.g. resolving conflicts, undoing or
committing changes, etc.).
The reapply command can also take --[no-]cone and
--[no-]sparse-index flags, with the same meaning as the flags from
the set command, in order to change which sparsity mode you are
using without needing to also respecify all sparsity paths.
disable
Disable the core.sparseCheckout config setting, and restore the
working directory to include all files.
init
Deprecated command that behaves like set with no specified paths.
May be removed in the future.
Historically, set did not handle all the necessary config settings,
which meant that both init and set had to be called. Invoking both
meant the init step would first remove nearly all tracked files
(and in cone mode, ignored files too), then the set step would add
many of the tracked files (but not ignored files) back. In addition
to the lost files, the performance and UI of this combination was
poor.
Also, historically, init would not actually initialize the
sparse-checkout file if it already existed. This meant it was
possible to return to a sparse-checkout without remembering which
paths to pass to a subsequent set or add command. However, --cone
and --sparse-index options would not be remembered across the
disable command, so the easy restore of calling a plain init
decreased in utility.
EXAMPLES
git sparse-checkout set MY/DIR1 SUB/DIR2
Change to a sparse checkout with all files (at any depth) under
MY/DIR1/ and SUB/DIR2/ present in the working copy (plus all files
immediately under MY/ and SUB/ and the toplevel directory). If
already in a sparse checkout, change which files are present in the
working copy to this new selection. Note that this command will
also delete all ignored files in any directory that no longer has
either tracked or non-ignored-untracked files present.
git sparse-checkout disable
Repopulate the working directory with all files, disabling sparse
checkouts.
git sparse-checkout add SOME/DIR/ECTORY
Add all files under SOME/DIR/ECTORY/ (at any depth) to the sparse
checkout, as well as all files immediately under SOME/DIR/ and
immediately under SOME/. Must already be in a sparse checkout
before using this command.
git sparse-checkout reapply
It is possible for commands to update the working tree in a way
that does not respect the selected sparsity directories. This can
come from tools external to Git writing files, or even affect Git
commands because of either special cases (such as hitting conflicts
when merging/rebasing), or because some commands didn’t fully
support sparse checkouts (e.g. the old recursive merge backend had
only limited support). This command reapplies the existing sparse
directory specifications to make the working directory match.
INTERNALS — SPARSE CHECKOUT
"Sparse checkout" allows populating the working directory sparsely. It
uses the skip-worktree bit (see git-update-index(1)) to tell Git
whether a file in the working directory is worth looking at. If the
skip-worktree bit is set, and the file is not present in the working
tree, then its absence is ignored. Git will avoid populating the
contents of those files, which makes a sparse checkout helpful when
working in a repository with many files, but only a few are important
to the current user.
The $GIT_DIR/info/sparse-checkout file is used to define the
skip-worktree reference bitmap. When Git updates the working directory,
it updates the skip-worktree bits in the index based on this file. The
files matching the patterns in the file will appear in the working
directory, and the rest will not.
INTERNALS — NON-CONE PROBLEMS
The $GIT_DIR/info/sparse-checkout file populated by the set and add
subcommands is defined to be a bunch of patterns (one per line) using
the same syntax as .gitignore files. In cone mode, these patterns are
restricted to matching directories (and users only ever need supply or
see directory names), while in non-cone mode any gitignore-style
pattern is permitted. Using the full gitignore-style patterns in
non-cone mode has a number of shortcomings:
• Fundamentally, it makes various worktree-updating processes (pull,
merge, rebase, switch, reset, checkout, etc.) require O(N*M)
pattern matches, where N is the number of patterns and M is the
number of paths in the index. This scales poorly.
• Avoiding the scaling issue has to be done via limiting the number
of patterns via specifying leading directory name or glob.
• Passing globs on the command line is error-prone as users may
forget to quote the glob, causing the shell to expand it into all
matching files and pass them all individually along to
sparse-checkout set/add. While this could also be a problem with
e.g. "git grep — *.c", mistakes with grep/log/status appear in the
immediate output. With sparse-checkout, the mistake gets recorded
at the time the sparse-checkout command is run and might not be
problematic until the user later switches branches or rebases or
merges, thus putting a delay between the user’s error and when they
have a chance to catch/notice it.
• Related to the previous item, sparse-checkout has an add subcommand
but no remove subcommand. Even if a remove subcommand were added,
undoing an accidental unquoted glob runs the risk of "removing too
much", as it may remove entries that had been included before the
accidental add.
• Non-cone mode uses gitignore-style patterns to select what to
include (with the exception of negated patterns), while .gitignore
files use gitignore-style patterns to select what to exclude (with
the exception of negated patterns). The documentation on
gitignore-style patterns usually does not talk in terms of matching
or non-matching, but on what the user wants to "exclude". This can
cause confusion for users trying to learn how to specify
sparse-checkout patterns to get their desired behavior.
• Every other git subcommand that wants to provide "special path
pattern matching" of some sort uses pathspecs, but non-cone mode
for sparse-checkout uses gitignore patterns, which feels
inconsistent.
• It has edge cases where the "right" behavior is unclear. Two
examples:
First, two users are in a subdirectory, and the first runs
git sparse-checkout set '/toplevel-dir/*.c'
while the second runs
git sparse-checkout set relative-dir
Should those arguments be transliterated into
current/subdirectory/toplevel-dir/*.c
and
current/subdirectory/relative-dir
before inserting into the sparse-checkout file? The user who typed
the first command is probably aware that arguments to set/add are
supposed to be patterns in non-cone mode, and probably would not be
happy with such a transliteration. However, many gitignore-style
patterns are just paths, which might be what the user who typed the
second command was thinking, and they'd be upset if their argument
wasn't transliterated.
Second, what should bash-completion complete on for set/add commands
for non-cone users? If it suggests paths, is it exacerbating the
problem above? Also, if it suggests paths, what if the user has a
file or directory that begins with either a '!' or '#' or has a '*',
'\', '?', '[', or ']' in its name? And if it suggests paths, will
it complete "/pro" to "/proc" (in the root filesytem) rather than to
"/progress.txt" in the current directory? (Note that users are
likely to want to start paths with a leading '/' in non-cone mode,
for the same reason that .gitignore files often have one.)
Completing on files or directories might give nasty surprises in
all these cases.
• The excessive flexibility made other extensions essentially
impractical. --sparse-index is likely impossible in non-cone mode;
even if it is somehow feasible, it would have been far more work to
implement and may have been too slow in practice. Some ideas for
adding coupling between partial clones and sparse checkouts are
only practical with a more restricted set of paths as well.
For all these reasons, non-cone mode is deprecated. Please switch to
using cone mode.
INTERNALS — CONE MODE HANDLING
The "cone mode", which is the default, lets you specify only what
directories to include. For any directory specified, all paths below
that directory will be included, and any paths immediately under
leading directories (including the toplevel directory) will also be
included. Thus, if you specified the directory Documentation/technical/
then your sparse checkout would contain:
• all files in the toplevel-directory
• all files immediately under Documentation/
• all files at any depth under Documentation/technical/
Also, in cone mode, even if no directories are specified, then the
files in the toplevel directory will be included.
When changing the sparse-checkout patterns in cone mode, Git will
inspect each tracked directory that is not within the sparse-checkout
cone to see if it contains any untracked files. If all of those files
are ignored due to the .gitignore patterns, then the directory will be
deleted. If any of the untracked files within that directory is not
ignored, then no deletions will occur within that directory and a
warning message will appear. If these files are important, then reset
your sparse-checkout definition so they are included, use git add and
git commit to store them, then remove any remaining files manually to
ensure Git can behave optimally.
See also the "Internals — Cone Pattern Set" section to learn how the
directories are transformed under the hood into a subset of the Full
Pattern Set of sparse-checkout.
INTERNALS — FULL PATTERN SET
The full pattern set allows for arbitrary pattern matches and
complicated inclusion/exclusion rules. These can result in O(N*M)
pattern matches when updating the index, where N is the number of
patterns and M is the number of paths in the index. To combat this
performance issue, a more restricted pattern set is allowed when
core.sparseCheckoutCone is enabled.
The sparse-checkout file uses the same syntax as .gitignore files; see
gitignore(5) for details. Here, though, the patterns are usually being
used to select which files to include rather than which files to
exclude. (However, it can get a bit confusing since gitignore-style
patterns have negations defined by patterns which begin with a !, so
you can also select files to not include.)
For example, to select everything, and then to remove the file unwanted
(so that every file will appear in your working tree except the file
named unwanted):
git sparse-checkout set --no-cone '/*' '!unwanted'
These patterns are just placed into the $GIT_DIR/info/sparse-checkout
as-is, so the contents of that file at this point would be
/*
!unwanted
See also the "Sparse Checkout" section of git-read-tree(1) to learn
more about the gitignore-style patterns used in sparse checkouts.
INTERNALS — CONE PATTERN SET
In cone mode, only directories are accepted, but they are translated
into the same gitignore-style patterns used in the full pattern set. We
refer to the particular patterns used in those mode as being of one of
two types:
1. Recursive: All paths inside a directory are included.
2. Parent: All files immediately inside a directory are included.
Since cone mode always includes files at the toplevel, when running git
sparse-checkout set with no directories specified, the toplevel
directory is added as a parent pattern. At this point, the
sparse-checkout file contains the following patterns:
/*
!/*/
This says "include everything immediately under the toplevel directory,
but nothing at any level below that."
When in cone mode, the git sparse-checkout set subcommand takes a list
of directories. The command git sparse-checkout set A/B/C sets the
directory A/B/C as a recursive pattern, the directories A and A/B are
added as parent patterns. The resulting sparse-checkout file is now
/*
!/*/
/A/
!/A/*/
/A/B/
!/A/B/*/
/A/B/C/
Here, order matters, so the negative patterns are overridden by the
positive patterns that appear lower in the file.
Unless core.sparseCheckoutCone is explicitly set to false, Git will
parse the sparse-checkout file expecting patterns of these types. Git
will warn if the patterns do not match. If the patterns do match the
expected format, then Git will use faster hash-based algorithms to
compute inclusion in the sparse-checkout. If they do not match, git
will behave as though core.sparseCheckoutCone was false, regardless of
its setting.
In the cone mode case, despite the fact that full patterns are written
to the $GIT_DIR/info/sparse-checkout file, the git sparse-checkout list
subcommand will list the directories that define the recursive
patterns. For the example sparse-checkout file above, the output is as
follows:
$ git sparse-checkout list
A/B/C
If core.ignoreCase=true, then the pattern-matching algorithm will use a
case-insensitive check. This corrects for case mismatched filenames in
the git sparse-checkout set command to reflect the expected cone in the
working directory.
INTERNALS — SUBMODULES
If your repository contains one or more submodules, then submodules are
populated based on interactions with the git submodule command.
Specifically, git submodule init -- <path> will ensure the submodule at
<path> is present, while git submodule deinit [-f] -- <path> will
remove the files for the submodule at <path> (including any untracked
files, uncommitted changes, and unpushed history). Similar to how
sparse-checkout removes files from the working tree but still leaves
entries in the index, deinitialized submodules are removed from the
working directory but still have an entry in the index.
Since submodules may have unpushed changes or untracked files, removing
them could result in data loss. Thus, changing sparse
inclusion/exclusion rules will not cause an already checked out
submodule to be removed from the working copy. Said another way, just
as checkout will not cause submodules to be automatically removed or
initialized even when switching between branches that remove or add
submodules, using sparse-checkout to reduce or expand the scope of
"interesting" files will not cause submodules to be automatically
deinitialized or initialized either.
Further, the above facts mean that there are multiple reasons that
"tracked" files might not be present in the working copy: sparsity
pattern application from sparse-checkout, and submodule initialization
state. Thus, commands like git grep that work on tracked files in the
working copy may return results that are limited by either or both of
these restrictions.
SEE ALSO
git-read-tree(1) gitignore(5)
GIT
Part of the git(1) suite
Git 2.39.2 02/28/2023 GIT-SPARSE-CHECKOU(1)
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