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@xxxxxxxxx>
---
Documentation/git-worktree.txt | 19 ++++++++++++++-
Documentation/gitrepository-layout.txt | 11 +++++++--
path.c | 2 ++
refs.c | 1 +
refs/files-backend.c | 14 ++++++++---
t/t0060-path-utils.sh | 2 ++
t/t1415-worktree-refs.sh | 33 ++++++++++++++++++++++++++
7 files changed, 76 insertions(+), 6 deletions(-)
create mode 100755 t/t1415-worktree-refs.sh
diff --git a/Documentation/git-worktree.txt b/Documentation/git-worktree.txt
index e2ee9fc21b..a50fbf8094 100644
--- a/Documentation/git-worktree.txt
+++ b/Documentation/git-worktree.txt
@@ -204,6 +204,22 @@ working trees, it can be used to identify worktrees. For example if
you only have two working trees, at "/abc/def/ghi" and "/abc/def/ggg",
then "ghi" or "def/ghi" is enough to point to the former working tree.
+REFS
+----
+In multiple working trees, some refs may be shared between all working
+trees, some refs are local. One example is HEAD is different for all
+working trees. This section is about the sharing rules.
+
+In general, all pseudo refs are per working tree and all refs starting
+with "refs/" are shared. Pseudo refs are ones like HEAD which are
+directly under GIT_DIR instead of inside GIT_DIR/refs. There are one
+exception to this: refs inside refs/bisect and refs/worktree is not
+shared.
+
+To access refs, it's best not to look inside GIT_DIR directly. Instead
+use commands such as linkgit:git-revparse[1] or linkgit:git-update-ref[1]
+which will handle refs correctly.
+
DETAILS
-------
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
`/path/other/test-next/.git/HEAD` or `/path/main/.git/HEAD`) while `git
rev-parse --git-path refs/heads/master` uses
$GIT_COMMON_DIR and returns `/path/main/.git/refs/heads/master`,
-since refs are shared across all working trees.
+since refs are shared across all working trees, except refs/bisect and
+refs/worktree.
See linkgit:gitrepository-layout[5] for more information. The rule of
thumb is do not make any assumption about whether a path belongs to
diff --git a/Documentation/gitrepository-layout.txt b/Documentation/gitrepository-layout.txt
index e85148f05e..89b616e049 100644
--- a/Documentation/gitrepository-layout.txt
+++ b/Documentation/gitrepository-layout.txt
@@ -95,8 +95,10 @@ refs::
References are stored in subdirectories of this
directory. The 'git prune' command knows to preserve
objects reachable from refs found in this directory and
- its subdirectories. This directory is ignored if $GIT_COMMON_DIR
- is set and "$GIT_COMMON_DIR/refs" will be used instead.
+ its subdirectories.
+ This directory is ignored (except refs/bisect and
+ refs/worktree) if $GIT_COMMON_DIR is set and
+ "$GIT_COMMON_DIR/refs" will be used instead.
refs/heads/`name`::
records tip-of-the-tree commit objects of branch `name`
@@ -165,6 +167,11 @@ hooks::
each hook. This directory is ignored if $GIT_COMMON_DIR is set
and "$GIT_COMMON_DIR/hooks" will be used instead.
+common::
+ When multiple working trees are used, most of files in
+ $GIT_DIR are per-worktree with a few known exceptions. All
+ files under 'common' however will be shared between all
+ working trees.
index::
The current index file for the repository. It is
diff --git a/path.c b/path.c
index 34f0f98349..bf4bb02a27 100644
--- a/path.c
+++ b/path.c
@@ -108,6 +108,7 @@ struct common_dir {
static struct common_dir common_list[] = {
{ 0, 1, 0, "branches" },
+ { 0, 1, 0, "common" },
{ 0, 1, 0, "hooks" },
{ 0, 1, 0, "info" },
{ 0, 0, 1, "info/sparse-checkout" },
@@ -118,6 +119,7 @@ static struct common_dir common_list[] = {
{ 0, 1, 0, "objects" },
{ 0, 1, 0, "refs" },
{ 0, 1, 1, "refs/bisect" },
+ { 0, 1, 1, "refs/worktree" },
{ 0, 1, 0, "remotes" },
{ 0, 1, 0, "worktrees" },
{ 0, 1, 0, "rr-cache" },
diff --git a/refs.c b/refs.c
index f07c775b50..67daf0918e 100644
--- a/refs.c
+++ b/refs.c
@@ -624,6 +624,7 @@ int dwim_log(const char *str, int len, struct object_id *oid, char **log)
static int is_per_worktree_ref(const char *refname)
{
return !strcmp(refname, "HEAD") ||
+ starts_with(refname, "refs/worktree/") ||
starts_with(refname, "refs/bisect/") ||
starts_with(refname, "refs/rewritten/");
}
diff --git a/refs/files-backend.c b/refs/files-backend.c
index 16ef9325e0..2dd77f9485 100644
--- a/refs/files-backend.c
+++ b/refs/files-backend.c
@@ -269,9 +269,9 @@ static void loose_fill_ref_dir(struct ref_store *ref_store,
closedir(d);
/*
- * Manually add refs/bisect, which, being per-worktree, might
- * not appear in the directory listing for refs/ in the main
- * repo.
+ * Manually add refs/bisect and refs/worktree, which, being
+ * per-worktree, might not appear in the directory listing for
+ * refs/ in the main repo.
*/
if (!strcmp(dirname, "refs/")) {
int pos = search_ref_dir(dir, "refs/bisect/", 12);
@@ -281,6 +281,14 @@ static void loose_fill_ref_dir(struct ref_store *ref_store,
dir->cache, "refs/bisect/", 12, 1);
add_entry_to_dir(dir, child_entry);
}
+
+ pos = search_ref_dir(dir, "refs/worktree/", 11);
+
+ if (pos < 0) {
+ struct ref_entry *child_entry = create_dir_entry(
+ dir->cache, "refs/worktree/", 11, 1);
+ add_entry_to_dir(dir, child_entry);
+ }
}
}
diff --git a/t/t0060-path-utils.sh b/t/t0060-path-utils.sh
index cd74c0a471..c7b53e494b 100755
--- a/t/t0060-path-utils.sh
+++ b/t/t0060-path-utils.sh
@@ -306,6 +306,8 @@ test_git_path GIT_COMMON_DIR=bar hooks/me bar/hooks/me
test_git_path GIT_COMMON_DIR=bar config bar/config
test_git_path GIT_COMMON_DIR=bar packed-refs bar/packed-refs
test_git_path GIT_COMMON_DIR=bar shallow bar/shallow
+test_git_path GIT_COMMON_DIR=bar common bar/common
+test_git_path GIT_COMMON_DIR=bar common/file bar/common/file
# In the tests below, $(pwd) must be used because it is a native path on
# Windows and avoids MSYS's path mangling (which simplifies "foo/../bar" and
diff --git a/t/t1415-worktree-refs.sh b/t/t1415-worktree-refs.sh
new file mode 100755
index 0000000000..16c91bef57
--- /dev/null
+++ b/t/t1415-worktree-refs.sh
@@ -0,0 +1,33 @@
+#!/bin/sh
+
+test_description='per-worktree refs'
+
+. ./test-lib.sh
+
+test_expect_success 'setup' '
+ test_commit initial &&
+ test_commit wt1 &&
+ test_commit wt2 &&
+ git worktree add wt1 wt1 &&
+ git worktree add wt2 wt2 &&
+ git checkout initial &&
+ git update-ref refs/worktree/foo HEAD &&
+ git -C wt1 update-ref refs/worktree/foo HEAD &&
+ git -C wt2 update-ref refs/worktree/foo HEAD
+'
+
+test_expect_success 'refs/worktree must not be packed' '
+ git pack-refs --all &&
+ test_path_is_missing .git/refs/tags/wt1 &&
+ test_path_is_file .git/refs/worktree/foo &&
+ test_path_is_file .git/worktrees/wt1/refs/worktree/foo &&
+ test_path_is_file .git/worktrees/wt2/refs/worktree/foo
+'
+
+test_expect_success 'refs/worktree are per-worktree' '
+ test_cmp_rev worktree/foo initial &&
+ ( cd wt1 && test_cmp_rev worktree/foo wt1 ) &&
+ ( cd wt2 && test_cmp_rev worktree/foo wt2 )
+'
+
+test_done
--
2.19.1.647.g708186aaf9
