Re: [PATCH v2 31/39] bundle: add new version for use with SHA-256

> @@ -23,17 +24,20 @@ static void add_to_ref_list(const struct object_id *oid, const char *name,
>  	list->nr++;
>  }
>  
> -static const struct git_hash_algo *detect_hash_algo(struct strbuf *buf)
> +static int parse_capability(struct bundle_header *header, const char *capability)
>  {
> -	size_t len = strcspn(buf->buf, " \n");
> -	int algo;
> -
> -	algo = hash_algo_by_length(len / 2);
> -	if (algo == GIT_HASH_UNKNOWN)
> -		return NULL;
> -	return &hash_algos[algo];
> +	const char *arg;
> +	if (skip_prefix(capability, "object-format=", &arg)) {
> +		int algo = hash_algo_by_name(arg);
> +		if (algo == GIT_HASH_UNKNOWN)
> +			return error(_("unable to detect hash algorithm"));
> +		header->hash_algo = &hash_algos[algo];
> +		return 0;
> +	}
> +	return error(_("unknown capability '%s'"), capability);
>  }

> +test_expect_success 'git bundle v3 rejects unknown extensions' '
> +	head -n2 bundle >new &&
> +	echo "@unknown=silly" >>new &&
> +	sed "1,2d" >>new &&
> +	test_must_fail git bundle verify new 2>output &&
> +	grep "unknown capability .unknown=silly." output