Array.push() and unique items

Question

I have a simple case of pushing unique values into array. It looks like this:

  this.items = [];

  add(item) {
    if(this.items.indexOf(item) > -1) {
           


        

Answer 1

Yep, it's a small mistake.

if(this.items.indexOf(item) === -1) {
    this.items.push(item);
    console.log(this.items);
}