public function testGetChanges()
 {
     $model = new Model();
     $model->client_id = 1;
     $model->amount = 100;
     $model->time = time();
     $fields_to_remove = array('client_id', 'amount');
     $model->removeFields($fields_to_remove);
     //Assert properties does not exist
     $this->assertFalse($model->attributeExist('client_id'));
     $this->assertFalse($model->attributeExist('amount'));
 }
 public function testAttributeExist()
 {
     $model = new Model();
     $model->date = null;
     //Asserts
     $this->assertTrue($model->attributeExist('date'));
 }