➕ Array.prototype.push() Polyfill

The push() method adds one or more elements to the end of an array and returns the new length.

✅ Implementation

Array.prototype.customPush = function (...elements) {
    for (let i = 0; i < elements.length; i++) {
        this[this.length] = elements[i]; // Add elements at the end of the array
    }
    return this.length; // Return the new length of the array
};

// Example usage:
const array = [1, 2, 3];
array.customPush(4, 5);

console.log(array); // Output: [1, 2, 3, 4, 5]
console.log(array.customPush(6, 7)); // Output: 7 (new length of array)
console.log(array); // Output: [1, 2, 3, 4, 5, 6, 7]

How It Works

1. Uses the rest parameter (...elements)
   • Allows multiple arguments to be passed and handled dynamically.
2. Iterates over new elements
   • Adds each element at this.length, ensuring insertion at the end.
3. Returns the new length
   • Mimics push() behavior by returning the updated length.

Edge Cases Handled

✔ Works with multiple elements: customPush(4, 5, 6)

✔ Works with an empty array: [].customPush(1, 2, 3)

✔ Works with no arguments: array.customPush() (returns unchanged length)

✔ Appends elements in order

This implementation is simple, efficient, and follows the behavior of Array.prototype.push exactly.