Mongolid\ManagerTest::testShouldInitializeOnce PHP Method

    public function testShouldInitializeOnce()
    {
        // Arrange
        $manager = new Manager();
        $this->callProtected($manager, 'init');
        // Assertion
        $this->assertAttributeEquals($manager, 'singleton', Manager::class);
        $this->assertAttributeInstanceOf(Container::class, 'container', $manager);
        $this->assertAttributeInstanceOf(Pool::class, 'connectionPool', $manager);
        $this->assertAttributeInstanceOf(CacheComponentInterface::class, 'cacheComponent', $manager);
        $container = $manager->container;
        $this->callProtected($manager, 'init');
        // Initializes again to make sure that it will not instantiate a new container
        $this->assertAttributeEquals($container, 'container', $manager);
    }