public function testConcatNeverEmpty()
{
$e1 = $this->createHotObservable([onNext(150, 1), onCompleted(230)]);
$e2 = Observable::never();
$results = $this->scheduler->startWithCreate(function () use($e1, $e2) {
return $e2->concat($e1);
});
$this->assertMessages([], $results->getMessages());
}