model.js

class UserModel {
	user = {
  	firstName: 'Jane',
    middleName: 'Liz',
    lastName: 'Doe',
  };
  
  getFullName({ short } = {}) {
  	const { firstName, middleName, lastName } = this.user;
  	if (short) return firstName + ' ' + lastName;
    
    return firstName + ' ' + middleName + ' ' + lastName;
  }
}