function shouldThrow(func, errorMessage) {
    var errorThrown = false;
    var error = null;
    try {
        func();
    } catch (e) {
        errorThrown = true;
        error = e;
    }
    if (!errorThrown)
        throw new Error('not thrown');
    if (String(error) !== errorMessage)
        throw new Error(`bad error: ${String(error)}`);
}

function *gen()
{
}

shouldThrow(() => {
    new gen();
}, `TypeError: function is not a constructor (evaluating 'new gen()')`);

class A {
    static *staticGen()
    {
    }

    *gen()
    {
    }
};

shouldThrow(() => {
    let a = new A();
    new a.gen();
}, `TypeError: function is not a constructor (evaluating 'new a.gen()')`);

shouldThrow(() => {
    new A.staticGen();
}, `TypeError: function is not a constructor (evaluating 'new A.staticGen()')`);