Add a place for (not) sharing stuff between worktrees
When multiple worktrees are used, we need rules to determine if something belongs to one worktree or all of them. Instead of keeping adding rules when new stuff comes (*), have a generic rule: - Inside $GIT_DIR, which is per-worktree by default, add $GIT_DIR/common which is always shared. New features that want to share stuff should put stuff under this directory. - Inside refs/, which is shared by default except refs/bisect, add refs/worktree/ which is per-worktree. We may eventually move refs/bisect to this new location and remove the exception in refs code. (*) And it may also include stuff from external commands which will have no way to modify common/per-worktree rules. Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Nguyễn Thái Ngọc Duy committed
Sep 29, 2018 at 21:10 UTC
8aff1a9ca5a266020fe5b1bd8c54228581e34530
7 files changed
+76
-6
Documentation/git-worktree.txt
+18
-1
@@ -204,6 +204,22 @@ working trees, it can be used to identify worktrees. For example if
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you only have two working trees, at "/abc/def/ghi" and "/abc/def/ggg",
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then "ghi" or "def/ghi" is enough to point to the former working tree.
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+REFS
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+----
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+In multiple working trees, some refs may be shared between all working
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+trees, some refs are local. One example is HEAD is different for all
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+working trees. This section is about the sharing rules.
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+
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+In general, all pseudo refs are per working tree and all refs starting
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+with "refs/" are shared. Pseudo refs are ones like HEAD which are
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+directly under GIT_DIR instead of inside GIT_DIR/refs. There are one
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+exception to this: refs inside refs/bisect and refs/worktree is not
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+shared.
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+
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+To access refs, it's best not to look inside GIT_DIR directly. Instead
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+use commands such as linkgit:git-revparse[1] or linkgit:git-update-ref[1]
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+which will handle refs correctly.
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+
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DETAILS
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-------
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Each linked working tree has a private sub-directory in the repository's
@@ -228,7 +244,8 @@ linked working tree `git rev-parse --git-path HEAD` returns
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`/path/other/test-next/.git/HEAD` or `/path/main/.git/HEAD`) while `git
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rev-parse --git-path refs/heads/master` uses
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$GIT_COMMON_DIR and returns `/path/main/.git/refs/heads/master`,
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-since refs are shared across all working trees.
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+since refs are shared across all working trees, except refs/bisect and
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+refs/worktree.
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See linkgit:gitrepository-layout[5] for more information. The rule of
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thumb is do not make any assumption about whether a path belongs to
Documentation/gitrepository-layout.txt
+9
-2
@@ -95,8 +95,10 @@ refs::
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References are stored in subdirectories of this
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directory. The 'git prune' command knows to preserve
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objects reachable from refs found in this directory and
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- its subdirectories. This directory is ignored if $GIT_COMMON_DIR
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- is set and "$GIT_COMMON_DIR/refs" will be used instead.
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+ its subdirectories.
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+ This directory is ignored (except refs/bisect and
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+ refs/worktree) if $GIT_COMMON_DIR is set and
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+ "$GIT_COMMON_DIR/refs" will be used instead.
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refs/heads/`name`::
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records tip-of-the-tree commit objects of branch `name`
@@ -165,6 +167,11 @@ hooks::
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each hook. This directory is ignored if $GIT_COMMON_DIR is set
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and "$GIT_COMMON_DIR/hooks" will be used instead.
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+common::
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+ When multiple working trees are used, most of files in
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+ $GIT_DIR are per-worktree with a few known exceptions. All
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+ files under 'common' however will be shared between all
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+ working trees.
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index::
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The current index file for the repository. It is
path.c
+2
@@ -108,6 +108,7 @@ struct common_dir {
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static struct common_dir common_list[] = {
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{ 0, 1, 0, "branches" },
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+ { 0, 1, 0, "common" },
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{ 0, 1, 0, "hooks" },
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{ 0, 1, 0, "info" },
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{ 0, 0, 1, "info/sparse-checkout" },
@@ -118,6 +119,7 @@ static struct common_dir common_list[] = {
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{ 0, 1, 0, "objects" },
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{ 0, 1, 0, "refs" },
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{ 0, 1, 1, "refs/bisect" },
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+ { 0, 1, 1, "refs/worktree" },
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{ 0, 1, 0, "remotes" },
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{ 0, 1, 0, "worktrees" },
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{ 0, 1, 0, "rr-cache" },
refs.c
+1
@@ -624,6 +624,7 @@ int dwim_log(const char *str, int len, struct object_id *oid, char **log)
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static int is_per_worktree_ref(const char *refname)
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{
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return !strcmp(refname, "HEAD") ||
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+ starts_with(refname, "refs/worktree/") ||
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starts_with(refname, "refs/bisect/") ||
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starts_with(refname, "refs/rewritten/");
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}
refs/files-backend.c
+11
-3
@@ -269,9 +269,9 @@ static void loose_fill_ref_dir(struct ref_store *ref_store,
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closedir(d);
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/*
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- * Manually add refs/bisect, which, being per-worktree, might
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- * not appear in the directory listing for refs/ in the main
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- * repo.
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+ * Manually add refs/bisect and refs/worktree, which, being
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+ * per-worktree, might not appear in the directory listing for
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+ * refs/ in the main repo.
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*/
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if (!strcmp(dirname, "refs/")) {
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int pos = search_ref_dir(dir, "refs/bisect/", 12);
@@ -281,6 +281,14 @@ static void loose_fill_ref_dir(struct ref_store *ref_store,
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dir->cache, "refs/bisect/", 12, 1);
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add_entry_to_dir(dir, child_entry);
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}
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+
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+ pos = search_ref_dir(dir, "refs/worktree/", 11);
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+
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+ if (pos < 0) {
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+ struct ref_entry *child_entry = create_dir_entry(
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+ dir->cache, "refs/worktree/", 11, 1);
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+ add_entry_to_dir(dir, child_entry);
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+ }
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}
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}
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t/t0060-path-utils.sh
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@@ -306,6 +306,8 @@ test_git_path GIT_COMMON_DIR=bar hooks/me bar/hooks/me
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test_git_path GIT_COMMON_DIR=bar config bar/config
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test_git_path GIT_COMMON_DIR=bar packed-refs bar/packed-refs
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test_git_path GIT_COMMON_DIR=bar shallow bar/shallow
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+test_git_path GIT_COMMON_DIR=bar common bar/common
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+test_git_path GIT_COMMON_DIR=bar common/file bar/common/file
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# In the tests below, $(pwd) must be used because it is a native path on
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# Windows and avoids MSYS's path mangling (which simplifies "foo/../bar" and
t/t1415-worktree-refs.sh
new
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@@ -0,0 +1,33 @@
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+#!/bin/sh
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+
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+test_description='per-worktree refs'
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+
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+. ./test-lib.sh
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+
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+test_expect_success 'setup' '
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+ test_commit initial &&
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+ test_commit wt1 &&
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+ test_commit wt2 &&
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+ git worktree add wt1 wt1 &&
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+ git worktree add wt2 wt2 &&
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+ git checkout initial &&
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+ git update-ref refs/worktree/foo HEAD &&
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+ git -C wt1 update-ref refs/worktree/foo HEAD &&
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+ git -C wt2 update-ref refs/worktree/foo HEAD
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+'
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+
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+test_expect_success 'refs/worktree must not be packed' '
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+ git pack-refs --all &&
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+ test_path_is_missing .git/refs/tags/wt1 &&
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+ test_path_is_file .git/refs/worktree/foo &&
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+ test_path_is_file .git/worktrees/wt1/refs/worktree/foo &&
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+ test_path_is_file .git/worktrees/wt2/refs/worktree/foo
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+'
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+
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+test_expect_success 'refs/worktree are per-worktree' '
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+ test_cmp_rev worktree/foo initial &&
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+ ( cd wt1 && test_cmp_rev worktree/foo wt1 ) &&
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+ ( cd wt2 && test_cmp_rev worktree/foo wt2 )
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+'
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+
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+test_done