public function testCountAmis()
 {
     $john = new User();
     $john->setName('john');
     $jean = new User();
     $jean->setName('jean');
     $phil = new User();
     $phil->setName('phil');
     $this->assertEquals(0, $john->countAmis());
     $john->setAmis(array($jean, $phil));
     $john->save();
     $this->assertEquals(2, $john->countAmis());
     $john->removeAmis();
     $this->assertEquals(0, $john->countAmis());
     $john->save();
     $this->assertEquals(0, $john->countAmis());
     $john->addAmi($phil);
     $this->assertEquals(1, $john->countAmis());
     $john->save();
     $this->assertEquals(1, $john->countAmis());
 }