public function add(PersonEntity $personEntity)
 {
     $newId = max(array_keys($this->people)) + 1;
     $personEntity->setId($newId);
     $this->setPeople($this->getPeople() + array($newId => $personEntity));
     $this->save();
     return $personEntity->getId();
 }
 /**
  * @depends testInstance
  * @dataProvider notInts
  * @expectedException \Exception
  * @expectedExceptionMessage Person ID must be an integer
  */
 public function testInvalidSetId($id)
 {
     $this->instance->setId($id);
 }