API for accessing indexes on proxies of arrays

[jeffcharles]

Is there an API available where I can access an index property on an object that is not an array?

The context is we maintain a serde deserializer for RQuickJS values and we need to be able to deserialize a proxy of an array with a custom getter on the proxy.

The code looks like this:

var arrayProxy = new Proxy([], {
  get: function(_target, key) {
    if (key === 'length') return 2;
    return Number(key);
  },
});

This is part of the 262 test suite for JSON.stringify and for this particular test case, it should stringify arrayProxy as "[0, 1]".

Object does not appear to have a method that invokes JS_GetPropertyUint32 which is what Array uses for Array::get. When trying to represent arrayProxy as an Array, Value::is_array returns false and Value::as_array returns none so I can't convert arrayProxy into Array. With 0.6.1 (before the switch to quickjs-ng), is_array returned true and as_array returned an Array inside a Some.

[Sytten]

@richarddd Do you have a take on this? Once I merge #570 we will have a safe Proxy primitive but the user still needs to recursively check for it. Do we want Array to support a proxy (or proxies) of an array? It might make sense since Object supports a proxy of an object.

[richarddd]

Yes I think we should