nil evaluation error

[i-kovalyov]

I founded that after decoding of 0xc0 byte (nil) from msgpack stream msgpack5 decides that stream is finished and then produces error.

I tried to replace text below from function tryDecode of decoder.js
case 0xc0:
return buildDecodeResult(null, 1)
with
case 0xc0:
return buildDecodeResult(undefined, 1)

This correction fixed error.

However mapping msgpack nil to "undefined" don't looks as best solution.

I tried to fix error another way so, that 0xc0 (nil) maps to null but it's not easy.
Null evaluation as end of stream is hardcoded in readable-stream.
function readableAddChunk of _stream_readable.js has following code:
...
if (chunk === null) {
state.reading = false;
onEofChunk(stream, state);
}
...

Any ideas how to fix this error?

[mcollina]

I think we should either allow to map nil to our own msgpack.Nil object, or output the result of tryDecode in tne decoder (via an option).

[i-kovalyov]

Added pull request fixing this error
#68

Msgpack nil is still mapped to null but during stream processing null temprarily replaced to undefined then replaced back to null.

Is this solution appropriate?