No encoding support for 64 bit format integers

[BurtHarris]

Looking at encode.js, it appears that there is no support for 64-bit integers. If encoding a large integer value (greater than 0xFFFFFFFF, the encoding logic does not use the option a 9-byte head.

This means, for example, that Number.MAX_SAFE_INTEGER (0x1FFFFFFFFFFFFF on 64-bit platforms) cannot be round-tripped.

[kriszyp]

These large numbers are encoded as double/float64, to match the representation used by JS. And I believe this is properly encoded as 64-bit and properly round-trips:

Number.MAX_SAFE_INTEGER -> 9007199254740991
let bytes = encode(Number.MAX_SAFE_INTEGER);
bytes.length -> 9;
decode(bytes) -> 9007199254740991

[KSDaemon]

IDK is it related or not. But I faced next problem:
Here is a simple bin data (in hex): 1B00000184B336D838 it is unsigned(1669454026808)

Here is the result of decoding it in node:

‌‌d = new Uint8Array('1B00000184B336D838'.match(/../g).map(h=>parseInt(h,16)));
Uint8Array(9)
dd = decode(d)
‌1669454026808

The same code in browser produces:

d = new Uint8Array('1B00000184B336D838'.match(/../g).map(h=>parseInt(h,16)));
Uint8Array(9)
dd = decode(d)
1669454026808n

I can't understand why? Is it a bug? I tried to play with different options, like:

const cbrxOptions = {
    useRecords: false,
    int64AsNumber: true,
    largeBigIntToFloat: true
};

But seems they all are not applied here.

[kriszyp]

@KSDaemon With your code, the numbers decode to bigints on node (by default), just like in the browser:

let d = new Uint8Array('1B00000184B336D838'.match(/../g).map(h=>parseInt(h,16)));
let dd = decode(d); 
console.log(dd); // 1669454026808n
dd = new CBOR.Decoder({ int64AsNumber: true }).decode(d);
console.log(dd); // 1669454026808

[KSDaemon]

Hm... Seems something goes wrong... Mb cache or smth else. Thnx! I'll recheck again!

[BurtHarris]

My issue has been addressed - by design; I'm marking it closed. @KSDaemon if you think there is still a problem, you should probably create a new issue.

I misunderstood that it would be encoded as major type 7 (rather than major type 0).