What is wrong with my object spread operator usage?

Question

var color3 = {
    name: 'Black',
    type: 'special',
    rating: 1
};

var rateColor3 = (colorName, Nrating) => ({ ...colorName, Nrating });
console.log(color3.rating); ///// 1
console.log(rateColor3(color3, 6).rating);//////1
console.log(color3.rating);//////1

I want to use object spread operator while keeping color3 immutable, But the output of my 2nd console.log is 1 instead of 6, what am i doing wrong?

Answer 1

You are assigning a the value 6 to the key NRating to the object, not the existing rating.

So your object would look like this:

{
    name: 'Black',
    type: 'special',
    rating: 1,
    Nrating: 6
}

To override the existing rating property, you have to do:

var rateColor3 = (colorName, Nrating) => ({ ...colorName, rating: Nrating });

or change your parameter Nrating to rating.

var color3 = {
    name: 'Black',
    type: 'special',
    rating: 1
};

var rateColor3 = (colorName, rating) => ({ ...colorName, rating });

console.log(rateColor3(color3, 6));