I would probably unifying the `model`. So that both in case you specify `url` via object or as direct value of `include` options, it doesn't matter. Like I shown for the value check. If we unify them when we populate the model, then here you have just to do:
```js
let { url } = model.include;
model.include.url = Rules();
model.include.url.add(...[].concat(url));
```

without the if/else.