How do you check if a relation is defined?

I have an User and a Cart model like this

class User extends Model {
static boot() {
    super.boot();

    this.addGlobalScope(builder => builder.with('cart'));
  }
  cart() {
    return this.hasOne('App/Models/Cart');
  }
}

class Cart extends Model {
  user() {
    return this.belongsTo('App/Models/User');
  }
}

now I want to check if a user has a cart (there’s no cart_id on user with this relation).

// this gets me the "cart" relation as well because of the global scope.
const user = await auth.getUser(); 
if (user.cart) {
    ...
}

how to I check if the user has an associated cart without fetching again? Boolean(user.cart) // always true, even if the user has no cart

[thetutlage]

If you have eagerloaded a relationship, then you can check it as.

if (user.getRelated('cart')) {
}

[somonek]

I think the question is still valid. Maybe you wanna remove the “invalid” tag so someone else can benefit from the answer.