React\Promise\PromiseTest\PromiseSettledTestTrait::doneShouldReturnAllowNullForSettledPromise PHP Method

    public function doneShouldReturnAllowNullForSettledPromise()
    {
        $adapter = $this->getPromiseTestAdapter();
        $adapter->settle();
        $this->assertNull($adapter->promise()->done(null, function () {
        }, null));
    }