The failure messages printed by these asserts are not helpful at all. Please consider either adding custom messages, or even better rewrite using chai:

```js
expect(user.toObject()).to.eql({ age: undefined, bio: 'me', name: 'Joe' });
expect(user.toObject(true)).to.eql(user.toObject());
expect(user.toObject(false)).to.eql({ age: 10, name: 'Joe', bio: 'me' });
```

Same applies to the second test below.