public function testTopic()
{
$topicName = 'test-topic';
$this->connection->getTopic(Argument::any())->willReturn(['name' => 'projects/project/topics/' . $topicName])->shouldBeCalledTimes(1);
$this->client->setConnection($this->connection->reveal());
$topic = $this->client->topic($topicName);
$this->assertInstanceOf(Topic::class, $topic);
$info = $topic->info();
$this->assertEquals($info['name'], 'projects/project/topics/' . $topicName);
}