required_unless:name validation not called when empty

[9mm]

I am using global validation rules: required_unless:0|max:255

I notice in my custom validator it doesnt get called though when the input is blank. (Im using indexes for target as the inputs dont have specific names)

Im using v4 and i cant seem to find this in the docs anywhere

defineRule('required_unless', (value, [targetIndex], ctx) => {
  if (isEmpty(value)) return true;
  const map = Object.entries(ctx.form).reduce((acc, [k, v]) => {
    const inputIndex = k.split('_')[2];
    acc[inputIndex] = v;
    return acc;
  }, {});
  const targetValue = map[targetIndex];
  if (isEmpty(value) && isEmpty(targetValue)) return 'Please fill in this field';
  return true;
});