public function testCRUD()
 {
     $this->_model->setData(['store_id' => 1, 'design' => 'Magento/blank', 'date_from' => date('Y-m-d', strtotime('-1 day')), 'date_to' => date('Y-m-d', strtotime('+1 day'))]);
     $this->_model->save();
     $this->assertNotEmpty($this->_model->getId());
     try {
         $model = \Magento\TestFramework\Helper\Bootstrap::getObjectManager()->create('Magento\\Theme\\Model\\Design');
         $model->loadChange(1);
         $this->assertEquals($this->_model->getId(), $model->getId());
         /* Design change that intersects with existing ones should not be saved, so exception is expected */
         try {
             $model->setId(null);
             $model->save();
             $this->fail('A validation failure is expected.');
         } catch (\Magento\Framework\Exception\LocalizedException $e) {
         }
         $this->_model->delete();
     } catch (\Exception $e) {
         $this->_model->delete();
         throw $e;
     }
     $model = \Magento\TestFramework\Helper\Bootstrap::getObjectManager()->create('Magento\\Theme\\Model\\Design');
     $model->loadChange(1);
     $this->assertEmpty($model->getId());
 }