Overwriting the default messages

Particle\Validator knows the concept of default messages and specific messages, so that means that you can either overwrite the defaults, or create a specific message for a single validation rule:

$v = new Validator;
$v->required('first_name')->lengthBetween(0, 5);
$v->required('last_name')->lengthBetween(0, 5);

$v->overwriteDefaultMessages([
    LengthBetween::TOO_LONG => 'It\'s too long, that value'
]);

$v->overwriteMessages([
    'first_name' => [
        LengthBetween::TOO_LONG => 'First name is too long, mate'
    ]
]);

$v->validate([
    'first_name' => 'this is too long',
    'last_name' => 'this is also too long',
]);


/**
 * Output:
 *
 *  [
 *     'first_name' => [
 *         LengthBetween::TOO_LONG => 'First name is too long, mate'
 *     ],
 *     'last_name' => [
 *         LengthBetween::TOO_LONG => 'It\'s too long, that value'
 *     ]
 * ];
 */

var_dump($v->getMessages());