Write a function which editUser if the user exist in the users array?

Question

I am using the array.map higher order function with a ternary operator to check the condition. I am not familiar with the method Object.assign

I tried a solution for the question, but it gives no return in the console, please verify and rectify my approach.

   const users = [
        {
            name:'Brook', 
            scores:75,
            skills:['HTM', 'CSS', 'JS'],
            age:16
        },
        {
            name:'Alex', 
            scores:80,
            skills:['HTM', 'CSS', 'JS'],
            age:18
        }, 
        {
            name:'David', 
            scores:75,
            skills:['HTM', 'CSS'],
            age:22
        }, 
        {
            name:'John', 
            scores:85,
            skills:['HTM'],
            age:25
        },
        {
            name:'Sara',
            scores:95,
            skills:['HTM', 'CSS', 'JS'],
            age: 26
        },
        {
            name:'Martha', 
            scores:80,
            skills:['HTM', 'CSS', 'JS'],
            age:18
        },
        {
            name:'Thomas',
            scores:90,
            skills:['HTM', 'CSS', 'JS'],
            age:20
        }
        ]

My solution: (NodeJS)

const editUser = (users, userUpdate) => {
    return users.map((user) => user.name == userUpdate ? Object.assign(user, { scores: userUpdate.scores, skills: userUpdate.skills, age: userUpdate.age }) : user);
}

Execution:

const userUpdate = {
    name: 'Alex',
    scores: 88,
    skills: ['HTM', 'CSS', 'JS', 'FullStack'],
    age: 20
}
console.log(editUser(users, userUpdate));

Answer 1

userUpdate is object that contain name property and must be compair user.name with userUpdate.name

in this problem you compair object with name and is not equal.

const editUser = (users, userUpdate) => {
    return users.map((user) => user.name == userUpdate.name ? Object.assign(user, { scores: userUpdate.scores, skills: userUpdate.skills, age: userUpdate.age }) : user);
};

Answer 2

We sometimes use object.asign() for clone an Object in JavaScript (without reference)

let user = { name: 'Alex'}
let newUser = user;
newUser.name = 'John';

console.log(newUser); //{ name: 'John' }
console.log(user); // { name: 'John' }

If you want to clone an object without reference you can use Object.assign() or three dots (...) is called spread operator in Javascript

I prefer three dots because it's a feature of ECS6.

Using of Object.assign():

let user = { name: 'Alex'}
let newUser = Object.assign({}, user);
newUser.name = 'John';

console.log(newUser);// { name: 'John' }
console.log(user);//{ name: 'Alex' }

Using three dots (...) or spread operator

let user = { name: 'Alex'}
let newUser = {...user};
newUser.name = 'John';

console.log(newUser); // { name: 'John' }
console.log(user); //{ name: 'Alex' }

You could visit this tutorial for more examples

For merging objects using Object.assign() or 'sperate operator', please check this tutorial

Answer your question is:

I think you don't need Object.assign() because keys of users and userUpdated is similar so just try like this:

const editUser = (users, userUpdate) => {
      return users.map((user) => user.name == userUpdate.name ? userUpdate: user);
};

Answer 3

You can use Array.prototype.findIndex() to get the user's index within the array with userUpdate.name

• The advantage is that in case of many users the search will stop immediately when the user is found

So you can modify that user if index is greater than 0

Code:

const users = [{name: 'Brook',scores: 75,skills: ['HTM', 'CSS', 'JS'],age: 16,},{name: 'Alex',scores: 80,skills: ['HTM', 'CSS', 'JS'],age: 18,},{name: 'David',scores: 75,skills: ['HTM', 'CSS'],age: 22,},{name: 'John',scores: 85,skills: ['HTM'],age: 25,},{name: 'Sara',scores: 95,skills: ['HTM', 'CSS', 'JS'],age: 26,},{name: 'Martha',scores: 80,skills: ['HTM', 'CSS', 'JS'],age: 18,},{name: 'Thomas',scores: 90,skills: ['HTM', 'CSS', 'JS'],age: 20,}]

const userUpdate = {
  name: 'Alex',
  scores: 88,
  skills: ['HTM', 'CSS', 'JS', 'FullStack'],
  age: 20,
}

const editUser = (users, userUpdate) => {
  const index = users.findIndex((u) => u.name === userUpdate.name)
  if (index > 0) {
    users[index] = userUpdate
  }
  return users
}
  

const result = editUser(users, userUpdate)

console.log(result)