diff --git a/Documentation/config/core.txt b/Documentation/config/core.txt index 852d2ba37a..bdbbee58b9 100644 --- a/Documentation/config/core.txt +++ b/Documentation/config/core.txt @@ -593,8 +593,14 @@ core.multiPackIndex:: multi-pack-index design document]. core.sparseCheckout:: - Enable "sparse checkout" feature. See section "Sparse checkout" in - linkgit:git-read-tree[1] for more information. + Enable "sparse checkout" feature. See linkgit:git-sparse-checkout[1] + for more information. + +core.sparseCheckoutCone:: + Enables the "cone mode" of the sparse checkout feature. When the + sparse-checkout file contains a limited set of patterns, then this + mode provides significant performance advantages. See + linkgit:git-sparse-checkout[1] for more information. core.abbrev:: Set the length object names are abbreviated to. If diff --git a/Documentation/git-sparse-checkout.txt b/Documentation/git-sparse-checkout.txt index c2cb19f80d..8535f0cf40 100644 --- a/Documentation/git-sparse-checkout.txt +++ b/Documentation/git-sparse-checkout.txt @@ -80,7 +80,9 @@ the sparse-checkout file. To repopulate the working directory with all files, use the `git sparse-checkout disable` command. -## FULL PATTERN SET + +FULL PATTERN SET +---------------- By default, the sparse-checkout file uses the same syntax as `.gitignore` files. @@ -95,6 +97,57 @@ 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.spareCheckoutCone` is enabled. + +The accepted patterns in the cone pattern set are: + +1. *Recursive:* All paths inside a directory are included. + +2. *Parent:* All files immediately inside a directory are included. + +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." +If we then add the folder `A/B/C` as a recursive pattern, the folders `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. + SEE ALSO -------- diff --git a/cache.h b/cache.h index 04cabaac11..4980ee198e 100644 --- a/cache.h +++ b/cache.h @@ -918,12 +918,14 @@ extern char *git_replace_ref_base; extern int fsync_object_files; extern int core_preload_index; -extern int core_apply_sparse_checkout; extern int precomposed_unicode; extern int protect_hfs; extern int protect_ntfs; extern const char *core_fsmonitor; +int core_apply_sparse_checkout; +int core_sparse_checkout_cone; + /* * Include broken refs in all ref iterations, which will * generally choke dangerous operations rather than letting diff --git a/config.c b/config.c index e7052b3977..d75f88ca0c 100644 --- a/config.c +++ b/config.c @@ -1364,6 +1364,11 @@ static int git_default_core_config(const char *var, const char *value, void *cb) return 0; } + if (!strcmp(var, "core.sparsecheckoutcone")) { + core_sparse_checkout_cone = git_config_bool(var, value); + return 0; + } + if (!strcmp(var, "core.precomposeunicode")) { precomposed_unicode = git_config_bool(var, value); return 0; diff --git a/environment.c b/environment.c index efa072680a..2a1a866659 100644 --- a/environment.c +++ b/environment.c @@ -67,6 +67,7 @@ enum object_creation_mode object_creation_mode = OBJECT_CREATION_MODE; char *notes_ref_name; int grafts_replace_parents = 1; int core_apply_sparse_checkout; +int core_sparse_checkout_cone; int merge_log_config = -1; int precomposed_unicode = -1; /* see probe_utf8_pathname_composition() */ unsigned long pack_size_limit_cfg; diff --git a/t/t1091-sparse-checkout-builtin.sh b/t/t1091-sparse-checkout-builtin.sh index c385c62c92..0b2715db52 100755 --- a/t/t1091-sparse-checkout-builtin.sh +++ b/t/t1091-sparse-checkout-builtin.sh @@ -148,6 +148,20 @@ test_expect_success 'set sparse-checkout using --stdin' ' test_cmp expect dir ' +test_expect_success 'cone mode: match patterns' ' + git -C repo config --worktree core.sparseCheckoutCone true && + rm -rf repo/a repo/folder1 repo/folder2 && + git -C repo read-tree -mu HEAD && + git -C repo reset --hard && + ls repo >dir && + cat >expect <<-EOF && + a + folder1 + folder2 + EOF + test_cmp expect dir +' + test_expect_success 'sparse-checkout disable' ' git -C repo sparse-checkout disable && test_path_is_missing repo/.git/info/sparse-checkout &&