Craft Rules and Validation

Question

Some of the changes in craft 3 have been killing me. I know Yii does validation using the public rules function. Here is a rules function I grabbed from the MatrixBlockType model.

function rules()
{
    return [
        [['id', 'fieldId', 'sortOrder'], 'number', 'integerOnly' => true],
    ];
}

My question is simple. I for the life of me can't find where the validator number is defined. I'm assuming it validates using Yii's NumberValidator.php function but can't verify that. Any ideas on where I can find the number validator?

Answer 1

I just figured out the answer so I'm going to post it if anyone else is asking this question. Yii accepts aliases as well as function/class names when evaluating the rules function. When using number you're really using an alias that points to the yii\validators\NumberValidator class. See yii2/validators/Validator.php to see a list of default aliases created by Yii.