How to create a nested array of object from an array of objects

Question

How Can I loop through this array of objects and change it so that the individual menu items are nested in the object menu_name?

const menus = [
 { menu_name: 'Entre', id:0 },
 {
 name: 'Soup',
 price: 14.99,
 id:1
 },
 {
 name: 'Chips & Salsa',
 price: 7.99,
 id:2
 },
 {
 name: 'Chicken Nuggets',
 price: 12.99,
 id:3
 },
 { menu_name: 'Sides', id:4 },
 {
 name: 'Fries',
 price: 4.99,
 id:5
 },
 {
 name: 'Drinks',
 price: 2.99,
 id:6
 },
 {
 name: 'Onion Rings',
 price: 5.99,
 id:7
 },
];

the end result should look like this for each menu_name object, where an array of menus is nested in the menu_name object

 {
 menu_name: 'Sides',
 menu: [
 {
 name: 'Fries',
 price: 4.99,
 },
 {
 name: 'Drinks',
 price: 2.99,
 },
 {
 name: 'Onion Rings',
 price: 5.99,
 },
 ],
 },

Answer 1

You can easily achieve this using reduce and object destructuring

const menus = [
 { menu_name: "Entre", id: 0 },
 {
 name: "Soup",
 price: 14.99,
 id: 1,
 },
 {
 name: "Chips & Salsa",
 price: 7.99,
 id: 2,
 },
 {
 name: "Chicken Nuggets",
 price: 12.99,
 id: 3,
 },
 { menu_name: "Sides", id: 4 },
 {
 name: "Fries",
 price: 4.99,
 id: 5,
 },
 {
 name: "Drinks",
 price: 2.99,
 id: 6,
 },
 {
 name: "Onion Rings",
 price: 5.99,
 id: 7,
 },
];
const result = menus.reduce((acc, curr) => {
 const { menu_name } = curr;
 if (menu_name) {
 acc.push({ menu_name, menu: [] });
 } else {
 const { name, price } = curr;
 acc[acc.length - 1].menu.push({ name, price });
 }
 return acc;
}, []);
console.log(result);

• DecPK: Is this what you want?
• Mamunur Rashid: Will you please explain how, acc[acc.length - 1].menu.push({ name, price }); // how this line is working? Why not acc.menu.push({ name, price }); // not working?
• DecPK: @MamunurRashid acc.menu.push({ name, price }); means acc is an object and menu is an array in which you are pushing an object which contains name and price. But what I've made structure is an array of objects. Since it an array so you need to find the object in which menu property exist and then push the object.

Answer 2

var newMenu = [];
menus.forEach(menu=>{
 if(menu.menu_name){
 newMenu.push({...menu, menu: []})
 }else{
 newMenu[newMenu.length-1].menu.push(menu)
 }
});