Required rule bug

[Delpfine]

Field 'cnn' range in 0 to 9, if field cnn=0 get error The field is required and has not been specified.

$val->addField('cnn')
            ->number()
            ->required()
            ->numericMax('9')
            ->numericMin('0');

Bug in /vendor/fuelphp/validation/src/Rule/Required.php line 53
return ($value === 0 or $value === false or ! empty($value));

phpDoc Note:

No warning is generated if the variable does not exist. That means empty() is essentially the concise equivalent to !isset($var) || $var == false.