public function testChangeSet()
 {
     $object = new \stdClass();
     $changeSet = new ChangeSet($object);
     $this->assertSame($object, $changeSet->getObject());
     $this->assertFalse($changeSet->hasChangedField('username'));
     $change = new Change('username', 'jwage', 'jonwage');
     $changeSet->addChange($change);
     $this->assertTrue($changeSet->hasChangedField('username'));
     $this->assertSame($change, $changeSet->getFieldChange('username'));
     $this->assertEquals('username', $change->getPropertyName());
     $this->assertEquals('jwage', $change->getOldValue());
     $this->assertEquals('jonwage', $change->getNewValue());
     $change->setNewValue('jon');
     $this->assertEquals('jon', $change->getNewValue());
 }