Re: [PATCH v5 2/5] worktree: create init_worktree_config()

> [...]
> Create a helper method, init_worktree_config(), that will be used in a
> later change to fix this behavior within 'git sparse-checkout set'. The
> method is carefully documented in worktree.h.
> [...]
> Signed-off-by: Derrick Stolee <dstolee@microsoft.com>
> ---
> diff --git a/worktree.c b/worktree.c
> @@ -826,3 +827,72 @@ int should_prune_worktree(const char *id, struct strbuf *reason, char **wtpath,
> +int init_worktree_config(struct repository *r)
> +{
> +       int res = 0;
> +       int bare = 0;
> +       struct config_set cs = { { 0 } };
> +       const char *core_worktree;
> +       char *common_config_file = xstrfmt("%s/config", r->commondir);
> +       char *main_worktree_file = xstrfmt("%s/config.worktree", r->commondir);
> +
> +       /*
> +        * If the extension is already enabled, then we can skip the
> +        * upgrade process.
> +        */
> +       if (repository_format_worktree_config)
> +               return 0;
> +       if ((res = git_config_set_gently("extensions.worktreeConfig", "true")))
> +               return error(_("failed to set extensions.worktreeConfig setting"));

> +
> +       git_configset_init(&cs);
> +       git_configset_add_file(&cs, common_config_file);
> +
> +       /*
> +        * If core.bare is true in the common config file, then we need to
> +        * move it to the base worktree's config file or it will break all
> +        * worktrees. If it is false, then leave it in place because it
> +        * _could_ be negating a global core.bare=true.
> +        */

> +       if (!git_configset_get_bool(&cs, "core.bare", &bare) && bare) {
> +               if ((res = move_config_setting("core.bare", "true",
> +                                              common_config_file,
> +                                              main_worktree_file)))
> +                       goto cleanup;
> +       }
> +       /*
> +        * If core.worktree is set, then the base worktree is located
> +        * somewhere different than the parent of the common Git dir.
> +        * Relocate that value to avoid breaking all worktrees with this
> +        * upgrade to worktree config.
> +        */

> +       if (!git_configset_get_string_tmp(&cs, "core.worktree", &core_worktree)) {
> +               if ((res = move_config_setting("core.worktree", core_worktree,
> +                                              common_config_file,
> +                                              main_worktree_file)))
> +                       goto cleanup;
> +       }
> +
> +       /*
> +        * Ensure that we use worktree config for the remaining lifetime
> +        * of the current process.
> +        */
> +       repository_format_worktree_config = 1;
> +
> +cleanup:
> +       git_configset_clear(&cs);
> +       free(common_config_file);
> +       free(main_worktree_file);
> +       return res;
> +}