/**
  * @dataProvider  storageClassProvider
  */
 public function testStorageClass($metadata)
 {
     $mock = $this->getS3Client();
     $mock->shouldReceive('headObject')->once()->andReturn(Mockery::self());
     $mock->shouldReceive('getAll')->once()->andReturn($metadata);
     $adapter = new Adapter($mock, 'bucketname');
     $result = $adapter->getStorageClass('object.ext');
     $this->assertTrue(!empty($result));
 }