[PATCH v2 2/6] worktree: stop supporting moving worktrees manually

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

The current update_linked_gitdir() has a bug that can create "gitdir"
file in non-multi-worktree setup. Worse, sometimes it can write relative
path to "gitdir" file, which will not work (e.g. "git worktree list"
will display the worktree's location incorrectly)

Instead of fixing this, we step back a bit. The original design was
probably not well thought out. For now, if the user manually moves a
worktree, they have to fix up "gitdir" file manually or the worktree
will get pruned.

Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
---
 Documentation/git-worktree.txt |  6 ++----
 setup.c                        | 12 ------------
 2 files changed, 2 insertions(+), 16 deletions(-)

diff --git a/Documentation/git-worktree.txt b/Documentation/git-worktree.txt
index 5b9ad04..4814f48 100644
--- a/Documentation/git-worktree.txt
+++ b/Documentation/git-worktree.txt
@@ -33,10 +33,8 @@ The working tree's administrative files in the repository (see
 clean up any stale administrative files.
 
 If you move a linked working tree to another file system, or
-within a file system that does not support hard links, you need to run
-at least one git command inside the linked working tree
-(e.g. `git status`) in order to update its administrative files in the
-repository so that they do not get automatically pruned.
+within a file system that does not support hard links, you need to update
+$GIT_DIR/worktrees/<id>/gitdir so that they do not get automatically pruned.
 
 If a linked working tree is stored on a portable device or network share
 which is not always mounted, you can prevent its administrative files from
diff --git a/setup.c b/setup.c
index d343725..6ee2b23 100644
--- a/setup.c
+++ b/setup.c
@@ -434,17 +434,6 @@ static int check_repository_format_gently(const char *gitdir, int *nongit_ok)
 	return ret;
 }
 
-static void update_linked_gitdir(const char *gitfile, const char *gitdir)
-{
-	struct strbuf path = STRBUF_INIT;
-	struct stat st;
-
-	strbuf_addf(&path, "%s/gitdir", gitdir);
-	if (stat(path.buf, &st) || st.st_mtime + 24 * 3600 < time(NULL))
-		write_file(path.buf, "%s", gitfile);
-	strbuf_release(&path);
-}
-
 /*
  * Try to read the location of the git directory from the .git file,
  * return path to git directory if found.
@@ -514,7 +503,6 @@ const char *read_gitfile_gently(const char *path, int *return_error_code)
 		error_code = READ_GITFILE_ERR_NOT_A_REPO;
 		goto cleanup_return;
 	}
-	update_linked_gitdir(path, dir);
 	path = real_path(dir);
 
 cleanup_return:
-- 
2.7.0.96.g5373197