setup: suppress implicit "." work-tree for bare repos
If an explicit GIT_DIR is given without a working tree, we
implicitly assume that the current working directory should
be used as the working tree. E.g.,:
GIT_DIR=/some/repo.git git status
would compare against the cwd.
Unfortunately, we fool this rule for sub-invocations of git
by setting GIT_DIR internally ourselves. For example:
git init foo
cd foo/.git
git status ;# fails, as we expect
git config alias.st status
git status ;# does not fail, but should
What happens is that we run setup_git_directory when doing
alias lookup (since we need to see the config), set GIT_DIR
as a result, and then leave GIT_WORK_TREE blank (because we
do not have one). Then when we actually run the status
command, we do setup_git_directory again, which sees our
explicit GIT_DIR and uses the cwd as an implicit worktree.
It's tempting to argue that we should be suppressing that
second invocation of setup_git_directory, as it could use
the values we already found in memory. However, the problem
still exists for sub-processes (e.g., if "git status" were
an external command).
You can see another example with the "--bare" option, which
sets GIT_DIR explicitly. For example:
git init foo
cd foo/.git
git status ;# fails
git --bare status ;# does NOT fail
We need some way of telling sub-processes "even though
GIT_DIR is set, do not use cwd as an implicit working tree".
We could do it by putting a special token into
GIT_WORK_TREE, but the obvious choice (an empty string) has
some portability problems.
Instead, we add a new boolean variable, GIT_IMPLICIT_WORK_TREE,
which suppresses the use of cwd as a working tree when
GIT_DIR is set. We trigger the new variable when we know we
are in a bare setting.
The variable is left intentionally undocumented, as this is
an internal detail (for now, anyway). If somebody comes up
with a good alternate use for it, and once we are confident
we have shaken any bugs out of it, we can consider promoting
it further.
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
diff --git a/git.c b/git.c
index d33f9b3..0ffea57 100644
--- a/git.c
+++ b/git.c
@@ -125,6 +125,7 @@
static char git_dir[PATH_MAX+1];
is_bare_repository_cfg = 1;
setenv(GIT_DIR_ENVIRONMENT, getcwd(git_dir, sizeof(git_dir)), 0);
+ setenv(GIT_IMPLICIT_WORK_TREE_ENVIRONMENT, "0", 1);
if (envchanged)
*envchanged = 1;
} else if (!strcmp(cmd, "-c")) {