Extends
lithium\test\Unit
When the Accept-Language is empty, it should return `null`.
Source
public function testPreferredEmpty() {
$available = array('fr', 'de');
$request = new ActionRequest(array(
'env' => array('HTTP_ACCEPT_LANGUAGE' => '')
));
$result = Locale::preferred($request, $available);
$this->assertNull($result);
}