How does the Javascript Array Push code work internally

Question

What is the internal code logic for Push and Pop methods in javascript..?? How does Push method stores the values in Array.

Answer 1

We can try some tests and test behavior:

const arr1 = []
const { push: push1 } = arr

const arr2 = []
const { push: push2 } = arr

console.log(push1 === push2) // true
console.log(push1 === Array.prototype.push) // true

push1(1) // TypeError: Cannot convert undefined or null to object

push1.call(arr1, 1) // arr1: [1], arr2: []

push2.call(arr1, 2) // arr1: [1, 2], arr2: []

push1.bind(arr2)(1) // arr1: [1, 2], arr2: [1]

push.call(arr2, 2)

And we can say that push method uses this under the hood...