From ed5336a7541e19b267de53afc8d15cffdbde8286 Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Nguy=E1=BB=85n=20Th=C3=A1i=20Ng=E1=BB=8Dc=20Duy?= Date: Thu, 20 Aug 2009 20:47:05 +0700 Subject: [PATCH] Introduce "sparse checkout" MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit With skip-worktree bit, you can manually set it to unwanted files, then remove them: you would have the so-called sparse checkout. The disadvantages are: - Porcelain tools are not aware of this. Everytime you do an operation that may update working directory, skip-worktree may be cleared out. You have to set them again. - You still have to remove skip-worktree'd files manually, which is boring and ineffective. These will be addressed in the following patches. This patch gives an idea what is "sparse checkout" in Documentation/git-read-tree.txt. This file is chosen instead of git-checkout.txt because it is quite technical and user-unfriendly. I'd expect git-checkout.txt to have something when Porcelain support is done. Signed-off-by: Nguyễn Thái Ngọc Duy Signed-off-by: Junio C Hamano --- Documentation/git-read-tree.txt | 44 +++++++++++++++++++++++++++++++++ 1 file changed, 44 insertions(+) diff --git a/Documentation/git-read-tree.txt b/Documentation/git-read-tree.txt index 4a932b08c6..8b3971685a 100644 --- a/Documentation/git-read-tree.txt +++ b/Documentation/git-read-tree.txt @@ -360,6 +360,50 @@ middle of doing, and when your working tree is ready (i.e. you have finished your work-in-progress), attempt the merge again. +Sparse checkout +--------------- + +"Sparse checkout" allows to sparsely populate working directory. +It uses skip-worktree bit (see linkgit:git-update-index[1]) to tell +Git whether a file on working directory is worth looking at. + +"git read-tree" and other merge-based commands ("git merge", "git +checkout"...) can help maintaining skip-worktree bitmap and working +directory update. `$GIT_DIR/info/sparse-checkout` is used to +define the skip-worktree reference bitmap. When "git read-tree" needs +to update working directory, it will reset skip-worktree bit in index +based on this file, which uses the same syntax as .gitignore files. +If an entry matches a pattern in this file, skip-worktree will be +set on that entry. Otherwise, skip-worktree will be unset. + +Then it compares the new skip-worktree value with the previous one. If +skip-worktree turns from unset to set, it will add the corresponding +file back. If it turns from set to unset, that file will be removed. + +While `$GIT_DIR/info/sparse-checkout` is usually used to specify what +files are in. You can also specify what files are _not_ in, using +negate patterns. For example, to remove file "unwanted": + +---------------- +* +!unwanted +---------------- + +Another tricky thing is fully repopulating working directory when you +no longer want sparse checkout. You cannot just disable "sparse +checkout" because skip-worktree are still in the index and you working +directory is still sparsely populated. You should re-populate working +directory with the `$GIT_DIR/info/sparse-checkout` file content as +follows: + +---------------- +* +---------------- + +Then you can disable sparse checkout. Sparse checkout support in "git +read-tree" and similar commands is disabled by default. + + SEE ALSO -------- linkgit:git-write-tree[1]; linkgit:git-ls-files[1];