Implement map on a Prototype - Console.Log changing output

JavaScript
1

Apologies if I paste the code incorrectly, I am not sure the proper format for pasting code on forums.

Anyways, during the lesson called Implement map on a Prototype, I finished it with the following code.

Array.prototype.myMap = function(callback) {
const newArray = ;
// Only change code below this line

for(let i = 0; i <= this.length - 1; i++){

// console.log(newArray.push(callback(this[i], i, this)))

newArray.push(callback(this[i], i, this))

}
// Only change code above this line
return newArray;
};

console.log([1, 1, 2, 5, 2].myMap((element, index, array) => array[index + 1] || array[0]));

This passes the test for me and my uncommented console.log gives me a result of [ 1, 2, 5, 2, 1 ]. However, if I uncomment my commented console.log “console.log(newArray.push(callback(this[i], i, this)))” I get an answer of [ 1, 1, 2, 2, 5, 5, 2, 2, 1, 1 ] from the last console.log line of code and Run the Tests says that my answer is incorrect. What is going on here? Is console.log affecting my output?

2

Yes. You might assume that anything inside a console.log is just “looking” at some value and not really doing anything, but if it has to be evaluated it has to be run to do so. So a push in a console.log will still push those values to wherever you told it.

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