Merge branch 'sb/submodule-embed-gitdir'

A new submodule helper "git submodule embedgitdirs" to make it
easier to move embedded .git/ directory for submodules in a
superproject to .git/modules/ (and point the latter with the former
that is turned into a "gitdir:" file) has been added.

* sb/submodule-embed-gitdir:
  worktree: initialize return value for submodule_uses_worktrees
  submodule: add absorb-git-dir function
  move connect_work_tree_and_git_dir to dir.h
  worktree: check if a submodule uses worktrees
  test-lib-functions.sh: teach test_commit -C <dir>
  submodule helper: support super prefix
  submodule: use absolute path for computing relative path connecting

1 files changed, 37 insertions, 0 deletions

diff --git a/dir.c b/dir.c
index bfa8c8a9a5..d872cc1570 100644
--- a/dir.c
+++ b/dir.c
@@ -2748,3 +2748,40 @@ void untracked_cache_add_to_index(struct index_state *istate,
 {
 	untracked_cache_invalidate_path(istate, path);
 }
+
+/* Update gitfile and core.worktree setting to connect work tree and git dir */
+void connect_work_tree_and_git_dir(const char *work_tree_, const char *git_dir_)
+{
+	struct strbuf file_name = STRBUF_INIT;
+	struct strbuf rel_path = STRBUF_INIT;
+	char *git_dir = xstrdup(real_path(git_dir_));
+	char *work_tree = xstrdup(real_path(work_tree_));
+
+	/* Update gitfile */
+	strbuf_addf(&file_name, "%s/.git", work_tree);
+	write_file(file_name.buf, "gitdir: %s",
+		   relative_path(git_dir, work_tree, &rel_path));
+
+	/* Update core.worktree setting */
+	strbuf_reset(&file_name);
+	strbuf_addf(&file_name, "%s/config", git_dir);
+	git_config_set_in_file(file_name.buf, "core.worktree",
+			       relative_path(work_tree, git_dir, &rel_path));
+
+	strbuf_release(&file_name);
+	strbuf_release(&rel_path);
+	free(work_tree);
+	free(git_dir);
+}
+
+/*
+ * Migrate the git directory of the given path from old_git_dir to new_git_dir.
+ */
+void relocate_gitdir(const char *path, const char *old_git_dir, const char *new_git_dir)
+{
+	if (rename(old_git_dir, new_git_dir) < 0)
+		die_errno(_("could not migrate git directory from '%s' to '%s'"),
+			old_git_dir, new_git_dir);
+
+	connect_work_tree_and_git_dir(path, new_git_dir);
+}