Child interface should redeclare ambiguous parent member

[Schahen]

The interface DuplexOptions from this snippet of code:

interface InputOptions {
  highWaterMark?: number;
  encoding?: string;
  objectMode?: boolean;
}

interface OutputOptions {
  highWaterMark?: number;
  decodeStrings?: boolean;
  objectMode?: boolean;
  defaultEncoding?: string;
}

interface DuplexOptions extends InputOptions, OutputOptions {
}

Is compiled to following kotlin code

external interface DuplexOptions : InputOptions, OutputOptions

However it actually should explicitly redeclare highWaterMark and objectMode, otherwise one get:

class 'DuplexOptions' must override public open var highWaterMark: Number? defined in InputOptions because it inherits multiple interface methods of it

[Schahen]

I've just realised that nullable are translated similar which seems to me questionable:

interface InputOptions {
  a: number | undefined;
}

will become:

external interface InputOptions {
    var a: Number?
        get() = definedExternally
        set(value) = definedExternally
}