Rx\Functional\Operator\DistinctUntilChangedTest::distinct_until_changed_empty PHP Method

    public function distinct_until_changed_empty()
    {
        $xs = $this->createHotObservable([onNext(150, 1), onCompleted(250)]);
        $results = $this->scheduler->startWithCreate(function () use($xs) {
            return $xs->distinctUntilChanged();
        });
        $messages = $results->getMessages();
        $this->assertEquals(1, count($messages));
        $this->assertTrue($messages[0] instanceof Recorded && $messages[0]->getValue() instanceof OnCompletedNotification);
        $this->assertEquals(250, $messages[0]->getTime());
    }