解析 ASCII.LL 到 LLLL 配置失败！

[zhtianhe]

简单测试过程如下：
1、组16进制数串

1=null
2 Fixed[22] =                 31323334353637383930313233343536373839303154  
3 LL            =3232          31323334353637383930313233343536373839303154
4 LLL          =303232      31323334353637383930313233343536373839303154
5 LLLL        =30303232  31323334353637383930313233343536373839303154

2、cat test/test-9999.bin

3030313036383030303030780000000000000031323334353637383930313233343536373839303154323231323334353637383930313233343536373839303154303232313233343536373839303132333435363738393031543030323231323334353637383930313233343536373839303154

4、cat test/test-9999.json

{
	"name": "ISO 8583 v1987 HEX",
	"fields": {
		"0": {
			"type": "String",
			"length": 11,
			"description": "报文头【N7+N4】:PKGHEAD",
			"enc": "HexToASCII",
			"prefix": "ASCII.Fixed"
		},
		"1": {
			"type": "Bitmap",
			"length": 16,
			"description": "位图【B128】:Bitmap",
			"enc": "HexToASCII",
			"prefix": "ASCII.Fixed"
		},
		"2": {
			"type": "String",
			"length": 22,
			"description": "2.Fixed:",
			"enc": "HexToASCII",
			"prefix": "ASCII.Fixed"
		},
		"3": {
			"type": "String",
			"length": 99,
			"description": "3.LL:",
			"enc": "HexToASCII",
			"prefix": "ASCII.LL"
		},
		"4": {
			"type": "String",
			"length": 999,
			"description": "4.LLL:",
			"enc": "HexToASCII",
			"prefix": "ASCII.LLL"
		},
		"5": {
			"type": "String",
			"length": 9999,
			"description": "5.LLLL:",
			"enc": "HexToASCII",
			"prefix": "ASCII.LLLL"
		}		
	}
}

5、./iso8583.exe describe -spec-file test/test-9999.json test/test-9999.bin

Failed to create message from file: unpacking message: failed to unpack field 4 (4.LLL:): failed to decode content: not enough data to read
Trying to describe file anyway...
ISO 8583 v1987 HEX Message:
MTI.......................: 00106800000
Bitmap....................: 7800000000000000
Bitmap bits...............: 01111000 00000000 00000000 00000000 00000000 00000000 00000000 00000000
F000 报文头【N7+N4】:PKGHEAD...: 00106800000
F002 2.Fixed:.............: 123456789012345678901T
F003 3.LL:................: 2123456789012345678901T022123456
F004 4.LLL:...............:

预期结果:

ISO 8583 v1987 HEX Message:
MTI.......................: 00106800000
Bitmap....................: 7800000000000000
Bitmap bits...............: 01111000 00000000 00000000 00000000 00000000 00000000 00000000 00000000
F000 报文头【N7+N4】:PKGHEAD...: 00106800000
F002 2.Fixed:.............: 123456789012345678901T
F003 3.LL:...................: 123456789012345678901T
F004 4.LLL:.................: 123456789012345678901T
F005 5.LLLL:...............: 123456789012345678901T