use ChunkSpy.lua accur error:ChunkSpy53.lua:1344: bad argument #3 to 'format' (number expected, got nil)

[liyonglion]

lua ChunkSpy.lua --source test.lua It show that:

Pos   Hex Data           Description or Code
------------------------------------------------------------------------
0000                     ** source chunk: test1.lua
                         ** global header start **
0000  1B4C7561           header signature: "\27Lua"
0004  53                 version (major:minor hex digits)
0005  00                 format (0=official)
0006  19930D0A1A0A       LUAC_DATA: "\25\147\r\n\26\n"
ChunkSpy: A Lua 5.3 binary chunk disassembler
Version 0.9.9 (20150329)
Copyright (c) 2004-2006 Kein-Hong Man , 2014-2015 VirusCamp
The COPYRIGHT file describes the conditions under which this
software may be distributed (basically a Lua 5-style license.)

* Run with option -h or --help for usage information
ChunkSpy53.lua:1344: bad argument #3 to 'format' (number expected, got nil)

This is test.lua content:

local a
local b = 1
a = b

OS is mac,lua version is 5.3.3

[viruscamp]

lua ChunkSpy.lua --auto test.lua