Derived class __init__: __argnames__ definition not inherited

[ralphwetzel]

The (familiar) setup:

app/__init__.pyj:

from control.item import TestA, TestB

class TestApp():
    def __init__(self):
        self.tA = TestA(id="A")
        self.tB = TestB(id="B")
        self.tA.out()
        self.tB.out()

x = TestApp()

control/item.pyj:

class TestA():
    def __init__(self, id):
        self.id = id
    def out(self):
        console.log(self.id)

class TestB(TestA):
    pass

Running test.jsresults in

A
[Object: null prototype] { id: 'B', [Symbol(kwargs-object)]: true }

... expressing that there's an issue with self.id in TestB.

Walking through the code I'm convinced this is due to the fact that
a) TestB is missing the __argnames__ definition that should have been inherited from TestA ...
b) ρσ_interpolate_kwargs thus executes the !f.__argnames__ case ...

function ρσ_interpolate_kwargs(f, supplied_args) {
    var has_prop, kwobj, args, prop;
    if (!f.__argnames__) {
        return f.apply(this, supplied_args);
    }
    has_prop = Object.prototype.hasOwnProperty;
    kwobj = supplied_args.pop();

c) and wrongly packs the provided parameters into arguments:

TestA/arguments at the end of ρσ_interpolate_kwargs:

TestB/argumentsat the end of ρσ_interpolate_kwargs:

Consequentially the initialization of self.id in TestB pulls the wrong parameter - generating the issue indicated.