public function testGetPreviewUrl()
 {
     $item = $this->prophesize('core_kernel_classes_Resource');
     $itemModelProphecy = $this->prophesize('core_kernel_classes_Resource');
     $itemModelProphecy->getPropertyValues(new core_kernel_classes_Property(PROPERTY_ITEM_MODEL_SERVICE))->willReturn(array());
     $itemModel = $itemModelProphecy->reveal();
     $this->assertNull($this->itemsService->getPreviewUrl($item->reveal()));
 }