Compare 2 objects to create a new array of objects in javascript

Question

I have an two elements fruits and crates

fruits is an array containing a list of different fruits like:

["apple","orange","mango","pear"]

crates is an array of objects which contains fruits in it like :

[{id:1,fruit_name: "apple"},{id:2, fruit_name: "pear"}]

I want to create a new array of objects based following conditions: - check if an entity from fruits array is present in any array of crates.

If present then the final object should have the fruit_name property along with another property called tested set to true. If not present then tested should be false;

considering above scenario the final output should be as follows:

[
    {fruit_name: "apple", tested: true},
    {fruit_name: "orange", tested: false},
    {fruit_name: "mango", tested: false},
    {fruit_name: "pear", tested: true},
]

What I have tried is as follows:

fruits.forEach(x => {
                        crates.filter((y) => {
                            let temp;
                            if (x == y.fruit_name) {
                                temp = {
                                    fruit: x,
                                    tested: true
                                }
                            }
                            else {
                                temp = {
                                    time: x,
                                    tested: false
                                }
                            }
                            testedCrates.push(temp);
                        })
                    })

the problem with this is, it is returning each fruit two times with both values for tested property.

the output i get is as follows:

[
    {fruit: "apple", tested: true}, 
    {time: "apple", tested: false},
    {time: "orange", tested: false},
    {time: "orange", tested: false},
    {time: "mango", tested: false},
    {time: "mango", tested: false},
    {time: "pear", tested: false},
    {time: "pear", tested: false}
]

kindly suggest some fix for this. Additionally if there is a better way of doing this with es6 approach would be helpful. thanks in advance.

Hassan Imam · Accepted Answer · 2017-12-23 10:08:42Z

3

You can use array#map and array#some to check if a fruit exist in the crates.

var fruits = ["apple","orange","mango","pear"],
crates = [{id:1,fruit_name: "apple"},{id:2, fruit_name: "pear"}];

var result = fruits.map(fruit => {
  var tested = crates.some(({fruit_name}) => fruit_name === fruit);
  return {'fruit_name' : fruit, tested};
});
console.log(result);

edited Dec 23, 2017 at 10:08

answered Dec 23, 2017 at 10:03

Hassan Imam

22.6k6 gold badges45 silver badges53 bronze badges

Sign up to request clarification or add additional context in comments.

Comments

Ori Drori · Accepted Answer · 2017-12-23 10:02:54Z

1

Create a Set of fruits that exist in the crates, then map the fruits array to the wanted form:

const fruits = ["apple","orange","mango","pear"]
const crates = [{id:1,fruit_name: "apple"},{id:2, fruit_name: "pear"}];
const cratesSet = new Set(crates.map(({ fruit_name }) => fruit_name));

const result = fruits.map((fruit_name) => ({
  fruit_name,
  tests: cratesSet.has(fruit_name)
}));

console.log(result);

answered Dec 23, 2017 at 10:02

Ori Drori

196k32 gold badges243 silver badges233 bronze badges

Comments

Nina Scholz · Accepted Answer · 2017-12-23 10:03:07Z

1

You could take a Set for crates and iterate fruits for a new array while checking the set.

var fruits = ["apple", "orange", "mango", "pear"],
    crates = [{ id: 1, fruit_name: "apple" }, { id: 2, fruit_name: "pear" }],
    cSet = new Set(crates.map(({ fruit_name }) => fruit_name)),
    result = fruits.map(fruit_name => ({ fruit_name, tested: cSet.has(fruit_name) }));

console.log(result);

.as-console-wrapper { max-height: 100% !important; top: 0; }

answered Dec 23, 2017 at 10:03

Nina Scholz

388k26 gold badges367 silver badges417 bronze badges

Comments

DomA · Accepted Answer · 2017-12-23 10:07:19Z

1

fruits.map(fruit => ({
  fruit_name: fruit,
  tested: crates.some(crate => crate.fruit === fruit),
}));

answered Dec 23, 2017 at 10:07

DomA

1381 silver badge9 bronze badges

Comments

Vitaliy Andrianov · Accepted Answer · 2017-12-23 10:11:58Z

0

fruits.map(fruit=>({
    fruit_name: fruit,
    tested: crates.some(x=>x.fruit_name === fruit)
}))

answered Dec 23, 2017 at 10:11

Vitaliy Andrianov

3651 silver badge6 bronze badges

1 Comment

Donald Duck is with Ukraine Over a year ago

While this code may answer the question, providing additional context regarding how and/or why it solves the problem would improve the answer's long-term value.

Donald Duck is with Ukraine · Accepted Answer · 2017-12-23 12:30:45Z

0

fruits.forEach(x => {
    let temp = { fruit: x, tested: false }

    crates.filter(y => {
        if (x === y.fruit_name)
            temp = { fruit: x, tested: true }
})
testedCrates.push(temp);

edited Dec 23, 2017 at 12:30

Donald Duck is with Ukraine

9,00223 gold badges82 silver badges106 bronze badges

answered Dec 23, 2017 at 10:41

Pasha Abe

133 bronze badges

1 Comment

Donald Duck is with Ukraine Over a year ago

While this code may answer the question, providing additional context regarding how and/or why it solves the problem would improve the answer's long-term value.

Collectives™ on Stack Overflow

Compare 2 objects to create a new array of objects in javascript

6 Answers 6

Comments

Comments

Comments

Comments

1 Comment

1 Comment

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

6 Answers 6

Comments

Comments

Comments

Comments

1 Comment

1 Comment

Your Answer

Sign up or log in

Post as a guest

Related