public function testAddParameters()
{
$source = "key1=1&key2=2";
$qs = new Http\QueryString($source);
$qs->addParameters(array('key2' => 3, 'key3' => 2));
$this->assertEquals($qs->key2, 3);
$this->assertEquals("key1=1&key2=3&key3=2", $qs->__toString());
}