Support of options

[DmitryAstafyev]

Issue

Looks like supporting of option type (Option<T>) isn't fully implemented.

Rust code

use node_bindgen::derive::node_bindgen;

#[node_bindgen]
fn test(a: Option<i32>, b: Option<i32>) -> i32 {
    a.unwrap_or(b.unwrap_or(1))
}

On JS side I'm expecting to do as well:

console.log(nativeModuleRef.test(100,200)); // OK
console.log(nativeModuleRef.test(200)); // OK
console.log(nativeModuleRef.test(null, 300)); // FAIL
console.log(nativeModuleRef.test(200, null));// FAIL
console.log(nativeModuleRef.test(undefined, 300)); // FAIL
console.log(nativeModuleRef.test(undefined, undefined));// FAIL
console.log(nativeModuleRef.test()); // OK

For example from serde_json perspective Option::None equal to undefined and null as well. Parsing goes without issues and with undefined and with null and without definition of value on js-object.

Reproducing

I'm also attaching sources of working example.

# unpack
cd node-bindgen_issue_options
nj-cli build --release
node ./dist/lib.js

Suggestion

Value Option::None should have an equivalent on JS side - null and undefined as well. "From" rust world to JS world Option::None should be returned as null. Well in general my suggestion just to fit serde_json

node-bindgen_issue_options.zip

Many thanks in advance for your feedback.

[DmitryAstafyev]

@sehz please take a look: #280

[DmitryAstafyev]

@sehz somehow tests on mac are failed... all of them... even linux is green. It doesn't look like it related to suggested changes... Could you please join also and help with tests?

[sehz]

it probably that it is using old nodejs version. @morenol can you update that test?

[morenol]

It looks like it is happening on main too, because this PR is also failing #281

[DmitryAstafyev]

@sehz @morenol PR is green... looks like you fixed macos )

[DmitryAstafyev]

I guess it can be closed as well.