Using `this` with destructuring

this.js

function Item ({ name, id }) {
  this.id = id;
  this.name = name;
}

Item.prototype.getName = function () {
  return this.name;
};

function checkThis1 ({ getName }) {
  console.log(getName());
} // the context of `this` is lost by using destructuring so when the `getName` method is called
// its `this` will be the `this` of the context of `checkThis1`

function checkThis2 (item) {
  console.log(item.getName());
} // will print `"Jeff"` because the context of the `this` is an instance of Item

function checkThis3 ({ getName }) {
  console.log(getName.call({ name: 'Not Jeff' }));
} // will print `"Not Jeff"` because the `this` is lost by destructuring and the `.call()` creates
// the context for the `this` in the subsequent call to `.getName()`
 
checkThis1(new Item({ id: 1, name: 'Geoff' }));
checkThis2(new Item({ id: 2, name: 'Jeff' }));
checkThis3(new Item({ id: 3, name: 'Djeoff' }));

Modified this slightly to have an actual private property that wouldn't be available without accessing a function. Otherwise the setup is the same. If you turn getName into an actual getter, it would solve the this issue*:

class Item {
  constructor({ first, last }) {
    this.first = first;
    this.last = last;
  }

  get name() {
    return this.first && this.last ? `${this.first} ${this.last}` : undefined;
  }
}

function checkThis1({ name = 'Tomasz Piorek' }) {
  console.log(name);
}

function checkThis2(item) {
  console.log(item.name);
}

function checkThis3({ name }) {
  console.log(name.call({ first: 'Not', last: 'Terrence' }));// throws error since
  // getters are not technically a function but rather a pseudo-property
}

checkThis1(new Item({ first: 'Adam', last: 'Bankin' }));// prints "Adam Bankin"
checkThis1(new Item({ name: 'Adam Bankin' }));// prints "Tomasz Piorek"
checkThis2(new Item({ first: 'Jason', last: 'Delia' }));// prints "Jason Delia"
checkThis3(new Item({ first: 'Terrence', last: 'Keane' }));// throws error, sorry Terrence XD

*with the caveat that you can't apply another context, but maybe that's not needed?