public function testFromRow()
 {
     $row = array('timestamp' => $this->date->getTimestamp(), 'user' => 'test1', 'subject' => 'created_from');
     $activity = ActivityUsage::fromRow($row);
     $this->assertInstanceOf('OCA\\ocUsageCharts\\Entity\\Activity\\ActivityUsage', $activity);
     $this->assertEquals("created_from", $activity->getSubject());
     $this->assertEquals($this->date, $activity->getDate());
 }