public function testDefaultState()
 {
     $this->assertTrue($this->helper->hasHelpers());
     $this->assertTrue($this->helper->hasHelper(MarkerCluster::_DEFAULT));
     $this->assertTrue($this->helper->hasHelper(MarkerCluster::MARKER_CLUSTER));
     $this->assertCount(2, $this->helper->getHelpers());
     $this->assertInstanceOf('Ivory\\GoogleMap\\Helper\\Overlays\\MarkerCluster\\DefaultMarkerClusterHelper', $this->helper->getHelper(MarkerCluster::_DEFAULT));
 }