Wrapper method that should create and return a Javascript Generator object returns undefined

See the example Javascript code below. In the code, the method `generatorZero` should return a Generator object, but it instead returns `undefined`.

If you first store the Generator in a variable before returning it, it works as expected. This is demonstrated with the method `generatorZeroWorkaround`.

class Class {
    *generatorFrom(start) {
        while (true) {
            yield start++;
        }
    }

    generatorZero() {
        return this.generatorFrom(0);
    }

    generatorZeroWorkaround() {
        const g = this.generatorFrom(0);
        return g;
    }
}

const c = new Class();
print(c.generatorZero()); // undefined
print(c.generatorZeroWorkaround()); // [object Generator]

Steps to reproduce:

1. Put the above code in a file named bug.js
2. In the same directory create a file named bug.qml with the following contents:

   import QtQuick 6.0
   import "bug.js" as Logic
   
   Item {}

1. Run `qml bug.qml` and observe the output of the command