Value i128 serializer breaks cbor <=> json Value to Value conversions

[rslife]

Hello.

Starting with 8cfcea9, direct conversions between cbor Values and json Values is no longer possible.

I fully understand the rationale behind using one integer type to cover the full integer value range supported by cbor. But I wonder what are your thoughts on bringing back, what was admittedly accidental, support for this type of conversion.

[pyfisch]

Hello,

that is unfortuate. Can you post a complete example with code of a failed conversion?
I'd like to bring it back, but it may be easier to change serde-json to accept all number types.

[rslife]

use serde::{Serialize, Deserialize};
use serde_cbor::value::Value as CborValue;

#[derive(Deserialize, Serialize)]
struct Foo { x: i32 }

fn main() {
    let foo = Foo { x: -13 };

    let cbor_bytes = serde_cbor::ser::to_vec(&foo)
        .expect("failed to serialize to cbor bytes");
    let cbor_val: CborValue = serde_cbor::from_slice(&*cbor_bytes)
        .expect("failed to deserialize to cbor Value");

    println!("{:?}", cbor_val);

    let json_val = serde_json::to_value(cbor_val)
        .expect("failed conversion");

    println!("{:?}", json_val);
}

This obviously happens whenever integer values of any type (not just i32) are involved.

[pyfisch]

Thanks for the example code. Would you mind opening an issue for serde-rs/json and ask them to accept i128 integers for values if they are in the 64-bit range?

[pyfisch]

Would it help if serde-cbor Values emit an u64 for positive numbers and i64 for negative number whenever possible?

[rslife]

Would it help if serde-cbor Values emit an u64 for positive numbers and i64 for negative number whenever possible?

Probably yes.

[pyfisch]

@rslife would you like to submit a PR?

[rslife]

I will send a PR from my home account later.