public function testConcatEmptyThrow()
{
$e1 = $this->createHotObservable([onNext(150, 1), onCompleted(230)]);
$e2 = $this->createHotObservable([onNext(150, 1), onError(250, new \Exception('error'))]);
$results = $this->scheduler->startWithCreate(function () use($e1, $e2) {
return $e1->concat($e2);
});
$this->assertMessages([onError(250, new \Exception('error'))], $results->getMessages());
}