"Kaitai::Struct::ValidationNotEqualError" throws letters instead of HEX-bytes like in Java.

[Thorsten Schöning]

The following YAML leads to the following Ruby, which leads to the error message underneath for some special input. While the error message in itself is correct and expected, it's textual content is simply different from that e.g. thrown in Java and in my opinion makes it more difficult to debug the concrete problem. I would therefore like to suggest changing the error message to provide a HEX-string instead of letters.

# par_oms_dll_command:
seq:
  - id:       check_value
    contents: [0x44]
    if:       not is_value_supported

def _read
  if !(is_value_supported)
    @check_value = @_io.read_bytes(1)
    raise Kaitai::Struct::ValidationNotEqualError.new([68].pack('C*'), check_value, _io, "/seq/0") if not check_value == [68].pack('C*')
  end

The error message in Ruby:

C:/Users/TSCHOE~1/AppData/Local/Temp/d20201130-11540-138pb9d/par_oms_dll_command.rb:56:in `_read': /seq/0: at pos 2: validation failed: not equal, expected "D", but got "G" (Kaitai::Struct::ValidationNotEqualError)

The error message in Java:

2020-11-27 14:51:12,855 ERROR
de.am_soft.sm_mtg.backend.svcs.ws.WsPackets.process: Processing a packet failed.
io.kaitai.struct.KaitaiStream$ValidationNotEqualError: /seq/0: at
pos 2: validation failed: not equal, expected [44], but got [47]

The important difference is that I get HEX-bytes in Java and a string in Ruby. I can easily change the implementation in Ruby to output a HEX-string as well:

super("not equal, expected #{expected.inspect}, but got #{actual.inspect}", io, src_path)

vs.

super("not equal, expected #{expected.unpack("H*")}, but got #{actual.unpack("H*")}", io, src_path)

C:/Users/TSCHOE~1/AppData/Local/Temp/d20201130-19396-139eoqo/par_oms_dll_command.rb:56:in `_read': /seq/0: at pos 2: validation failed: not equal, expected ["44"], but got ["47"] (Kaitai::Struct::ValidationNotEqualError)

What is the correct thing to do here?