Google\Cloud\Tests\Snippets\PubSub\SubscriptionTest::testExists PHP Method

    public function testExists()
    {
        $snippet = $this->snippetFromMethod(Subscription::class, 'exists');
        $snippet->addLocal('subscription', $this->subscription);
        $this->connection->getSubscription(Argument::any())->shouldBeCalled();
        $this->subscription->setConnection($this->connection->reveal());
        $res = $snippet->invoke();
        $this->assertEquals('Subscription exists!', $res->output());
    }