public function testImplementsCount()
{
$data = new Collection();
$this->assertEquals(0, $data->count());
$data->add('key', 'value');
$this->assertEquals(1, count($data));
$data->add('key', 'value2');
$this->assertEquals(1, count($data));
$data->add('key_2', 'value3');
$this->assertEquals(2, count($data));
}