public function testMultipleField()
{
$validation = new Validation();
$validationMessages = ['name' => 'Name must be alpha.', 'type' => 'Type must by alpha.'];
$validation->add(['name', 'type'], new Alpha(['message' => $validationMessages]));
$messages = $validation->validate(['name' => 'Asd', 'type' => 'Asd']);
expect($messages->count())->equals(0);
$messages = $validation->validate(['name' => 'Asd123', 'type' => 'Asd']);
expect($messages->count())->equals(1);
expect($messages->offsetGet(0)->getMessage())->equals($validationMessages['name']);
$messages = $validation->validate(['name' => 'Asd123', 'type' => 'Asd123']);
expect($messages->count())->equals(2);
expect($messages->offsetGet(0)->getMessage())->equals($validationMessages['name']);
expect($messages->offsetGet(1)->getMessage())->equals($validationMessages['type']);
}