Rx\Functional\Operator\DistinctUntilChangedTest::distinct_until_changed_keyselector_div2 PHP Method

    public function distinct_until_changed_keyselector_div2()
    {
        $xs = $this->createHotObservable([onNext(150, 1), onNext(210, 2), onNext(220, 4), onNext(230, 3), onNext(240, 5), onCompleted(250)]);
        $results = $this->scheduler->startWithCreate(function () use($xs) {
            return $xs->distinctUntilKeyChanged(function ($x) {
                return $x % 2;
            });
        });
        $messages = $results->getMessages();
        $this->assertEquals(3, count($messages));
        $this->assertTrue($messages[0]->getValue() instanceof OnNextNotification);
        $this->assertTrue($messages[0]->getValue() == new OnNextNotification(2));
        $this->assertEquals(210, $messages[0]->getTime());
        $this->assertTrue($messages[1]->getValue() instanceof OnNextNotification);
        $this->assertTrue($messages[1]->getValue() == new OnNextNotification(3));
        $this->assertEquals(230, $messages[1]->getTime());
        $this->assertTrue($messages[2]->getValue() instanceof OnCompletedNotification);
        $this->assertEquals(250, $messages[2]->getTime());
    }