[PATCH] Preserve cwd in setup_git_directory()

["Nguyễn Thái Ngọc Duy" <pclouds@gmail.com>]

When GIT_DIR is not set, cwd is used to determine where .git is.
If core.worktree is set, setup_git_directory() needs to jump back
to the original cwd in order to calculate worktree, this leads to
incorrect .git location later in setup_work_tree().

Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
---
 setup.c             |    4 ++++
 t/t1501-worktree.sh |   13 ++++++++++++-
 2 files changed, 16 insertions(+), 1 deletions(-)

diff --git a/setup.c b/setup.c
index 6cf9094..ef58761 100644
--- a/setup.c
+++ b/setup.c
@@ -577,10 +577,14 @@ const char *setup_git_directory(void)
 	/* If the work tree is not the default one, recompute prefix */
 	if (inside_work_tree < 0) {
 		static char buffer[PATH_MAX + 1];
+		static char cwd[PATH_MAX + 1];
 		char *rel;
+		getcwd(cwd, PATH_MAX);
 		if (retval && chdir(retval))
 			die ("Could not jump back into original cwd");
 		rel = get_relative_cwd(buffer, PATH_MAX, get_git_work_tree());
+		if (retval && chdir(cwd))
+			die ("Could not jump back into original cwd");
 		return rel && *rel ? strcat(rel, "/") : NULL;
 	}
 
diff --git a/t/t1501-worktree.sh b/t/t1501-worktree.sh
index 2ee88d8..64f8dea 100755
--- a/t/t1501-worktree.sh
+++ b/t/t1501-worktree.sh
@@ -29,7 +29,18 @@ test_rev_parse() {
 }
 
 mkdir -p work/sub/dir || exit 1
-mv .git repo.git || exit 1
+
+git config core.worktree "$(pwd)"/work
+mv .git work || exit 1
+test_expect_success '--git-dir with relative .git' '
+	(
+	MYPWD="$(pwd)"
+	cd work/sub/dir &&
+	test "$MYPWD"/work/.git = "$(git rev-parse --git-dir)"
+	)
+'
+
+mv work/.git repo.git || exit 1
 
 say "core.worktree = relative path"
 GIT_DIR=repo.git
-- 
1.5.5.GIT