Inconsistent ObjectInstance.GetOwnProperties

[lofcz]

Version used

4.0.1

Describe the bug

I'm working on a Blazor debugger for Jint. Recently I've encountered a weird inconsistency - if the thing is intentional, feel free to yell at me. ObjectInstance.GetOwnProperties() behaves (at least from my perspective) differently for CLR ObjectWrapper and native Object instances.

For CLR objects, only properties and fields get reported:

// we take public properties and fields
foreach (var p in ClrType.GetProperties(BindingFlags.Static | BindingFlags.Instance | BindingFlags.Public))
{
    var indexParameters = p.GetIndexParameters();
    if (indexParameters.Length == 0)
    {
        var jsString = JsString.Create(p.Name);
        yield return jsString;
    }
}

foreach (var f in ClrType.GetFields(BindingFlags.Static | BindingFlags.Instance | BindingFlags.Public))
{
    var jsString = JsString.Create(f.Name);
    yield return jsString;
}

While native objects report properties, which are methods as well. For example:

var myTest = {
  myFn: () => { 
    return 4
  }
}

reports myFn when calling GetOwnProperties on a corresponding JsValue, while only props and fields are reported for CLR objects as per the code above.

While I understand that myFn is a property from the JS perspective and public void MyFn() is a method from CLR perspective, it still seems inconsistent, given we report fields from CLR objects already.
My understanding is that GetOwnProperties is the tool to check from the CLR side, how the JS interpreter sees the given object, hence my suggestion to include methods too.

Expected behavior

Methods of CLR objects are reported from GetOwnProperties (we include GetMethods result in the code above).

[lahma]

Adding public methods sounds reasonable as they can be invoked. Would you like to create a PR with some test coverage?

[lofcz]

Sure, I'll go ahead. Technically, I would consider this breaking, since consumers might be relying on the fact that the method in question works the way it does now, so this might warrant a 4.1 release.

[lahma]

One option is to add new enum flags property to interop options defining returned properties and omit methods for now.

[lofcz]

solved in #1947