Re: [PATCH v2 2/8] pack-objects: ensure tree/tag closure with '--stdin-packs=follow'

> @@ -4151,6 +4158,34 @@ static void read_stdin_packs(struct repository *repo,
>  			     show_object_pack_hint,
>  			     &mode);
>  
> +	/*
> +	 * Trees and tags need closure even when no commit reaches them.
> +	 * Defer adding these roots to revs.pending until the first walk
> +	 * finishes. Otherwise a subtree may be visited and marked SEEN
> +	 * before its commit's root tree, using "a" instead of "sub/a"
> +	 * for a blob's namehash and delta attributes.
> +	 *
> +	 * Tags may introduce more commits in the second walk, so this
> +	 * does not *always* guarantee that trees are always visited
> +	 * with their full paths.
> +	 */

> +	oidset_iter_init(&ctx.extra_roots, &iter);
> +	while ((oid = oidset_iter_next(&iter))) {
> +		struct object *obj = lookup_object(repo, oid);
> +
> +		if (!obj || !(obj->flags & SEEN))
> +			add_pending_oid(&revs, NULL, oid, 0);
> +	}
> +	if (revs.pending.nr) {
> +		if (prepare_revision_walk(&revs))
> +			die(_("revision walk setup failed"));
> +		traverse_commit_list(&revs,
> +				     show_commit_pack_hint,
> +				     show_object_pack_hint,
> +				     &mode);
> +	}
> +	oidset_clear(&ctx.extra_roots);
> +
>  	release_revisions(&revs);