git-sparse-checkout - Reduce your working tree to a subset of tracked files
git sparse-checkout <subcommand> [<options>]
This command is used to create sparse checkouts, which means that it changes the working tree from having all tracked files present, to only have a subset of them. 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 (which is recommended), 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.
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.
When --cone is passed or core.sparseCheckoutCone is enabled, the input list is considered a list of directories. This allows for better performance with a limited set of patterns (see CONE PATTERN SET below). The input format matches the output of git ls-tree --name-only. This includes interpreting pathnames that begin with a double quote (") as C-style quoted strings. Note that the set command will write patterns to the sparse-checkout file to include all files contained in those directories (recursively) as well as files that are siblings of ancestor directories. This may become the default in the future; --no-cone can be passed to request non-cone mode.
When --no-cone is passed or core.sparseCheckoutCone is not enabled, the input list is considered a list of patterns. This mode is harder to use and less performant, and is thus not recommended. See the "Sparse Checkout" section of git-read-tree(1) and the "Pattern Set" sections below for more details.
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.
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.
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.
"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.
To enable the sparse-checkout feature, run git sparse-checkout set to set the patterns you want to use.
To repopulate the working directory with all files, use the git sparse-checkout disable command.
FULL PATTERN SET¶
By default, the sparse-checkout file uses the same syntax as .gitignore files.
While $GIT_DIR/info/sparse-checkout is usually used to specify what files are included, you can also specify what files are not included, using negative patterns. For example, to remove the file unwanted:
CONE 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 accepted patterns in the cone pattern set are:
In addition to the above two patterns, we also expect that all files in the root directory are included. If a recursive pattern is added, then all leading directories are added as parent patterns.
By default, when running git sparse-checkout init, the root directory is added as a parent pattern. At this point, the sparse-checkout file contains the following patterns:
This says "include everything in root, but nothing two levels below root."
When in cone mode, the git sparse-checkout set subcommand takes a list of directories instead of a list of sparse-checkout patterns. In this mode, 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.
If core.sparseCheckoutCone=true, then 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.
In the cone mode case, 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.
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.
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.
Part of the git(1) suite