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Merge Objects in a array and increase count

[{name:"abc",value:5},{name:"abc",value:10},{name:"abc1",value:5},{name:"abc1",value:15}]
I want to merge it by name so that the new array will be
[{name:"abc",value:15},{name:"abc1",value:20}]
Can i do it with es6 or a simple function

Using reduce and without find or findIndex
const data = [{name:"abc",value:5},{name:"abc",value:10},{name:"abc1",value:5},{name:"abc1",value:15}];
const summedDataObj = data.reduce((acc, entry) => {
if (acc[entry.name]) acc[entry.name].value += entry.value;
else acc[entry.name] = entry;
return acc;
}, {});
const summedDataArr = Object.values(summedDataObj);
console.log(summedDataArr);

We can do it via Array.reduce()
let data = [{name:"abc",value:5},{name:"abc",value:10},{name:"abc1",value:5},{name:"abc1",value:15}]
let result = data.reduce((a,{name,value}) => {
let obj = a.find(e => e.name === name)
if(obj){
obj.value += value
}else{
a.push({name,value})
}
return a
},[])
console.log(result)

you can group the data by name using this function:
function groupBy(arr, prop) {
const map = new Map(Array.from(arr, obj => [obj[prop], []]));
arr.forEach(obj => map.get(obj[prop]).push(obj));
return Array.from(map.values());
}
this yields this result:
[
[
{"name": "abc", "value": 5},
{"name": "abc", "value": 10}
],
[
{"name": "abc1", "value": 5},
{"name": "abc1", "value": 15}
]
]
which can be aggregated by using reduce on each resulting array:
groupedData.map(entry=>entry.reduce((acc,cur)=>({
...acc,
value: acc.value + cur.value
})))
so all together we get:
function groupBy(arr, prop) {
const map = new Map(Array.from(arr, obj => [obj[prop], []]));
arr.forEach(obj => map.get(obj[prop]).push(obj));
return Array.from(map.values());
}
const data = [{name:"abc",value:5},{name:"abc",value:10},{name:"abc1",value:5},{name:"abc1",value:15}]
const aggregatedData = groupBy(data,"name")
.map(entry=>entry.reduce((acc,cur)=>({
...acc,
value:acc.value+cur.value
})))

const obj = [{name:"abc",value:5},{name:"abc",value:10},{name:"abc1",value:5},{name:"abc1",value:15}]
arr = obj.reduce((obj, item) => {
let find = obj.find(i => i.name === item.name && i.date === item.date);
let _d = {
...item
}
find ? (find.value += item.value ) : obj.push(_d);
return obj;
}, [])
console.log(arr);

const data = [{
name: "abc",
value: 5
},
{
name: "abc",
value: 10
},
{
name: "abc1",
value: 5
},
{
name: "abc1",
value: 15
},
];
const groupArr = data.reduce((r, a) => {
const idx = r.findIndex((el) => el.name === a.name);
idx === -1 ? r.push(a) : (r[idx].value += a.value);
return r;
}, []);
console.log(groupArr);

You can achieve this with the help of Array#reduce method.
Live Demo :
const arr = [{name:"abc",value:5},{name:"abc",value:10},{name:"abc1",value:5},{name:"abc1",value:15}];
const res = arr.reduce((obj, curr) => {
if (obj.hasOwnProperty(curr.name) && obj[curr.name].name === curr.name) {
obj[curr.name].value += curr.value
} else {
obj[curr.name] = curr;
}
return obj
}, {});
console.log(Object.values(res));

Is there any other way to check multiple values are present in array of object?

I have the below array of objects and I want to check if two different users are present in this array .if present i have to run some logic
let result = [{"name": "ABC"},{"name": "CDE"},{"name": "FGH"},{"name": "XYZ"}];
var newArr = [];
var hasMatch = result.filter(function(val) {
if (val.name == "FGH"){
newArr.push(val)
} else if (val.name == "ABC") {
newArr.push(val)
}
});
console.log(newArr)
if (newArr.length == 2) {
//do logic
}
It's working as expected but I'm looking for a different approach for this. could someone advise?

Not optimized for speed, but does the job
let arr = [
{
"name": "ABC"
},
{
"name": "CDE"
},
{
"name": "FGH"
},
{
"name": "XYZ"
}
];
let users = ["ABC", "XYZ"]
let hasAllUsers = users.every(user => arr.some(item => item.name == user))
console.log(hasAllUsers)
// if(hasAllUser) {...}

It's a pretty roundabout way to zero in on the logic you're trying to express. Note how the result in hasMatch is never even used. That's really all you're looking for, does the array "have the values".
There's no need to push values to another array and check if that array has values. Just check of the original array has them.
Which could be as simple as:
let result = [{"name": "ABC"},{"name": "CDE"},{"name": "FGH"},{"name": "XYZ"}];
if (result.filter(r => r.name === "FGH" || r.name === "ABC").length === 2) {
// do logic
}
Or if you want to refactor the condition into a variable:
let result = [{"name": "ABC"},{"name": "CDE"},{"name": "FGH"},{"name": "XYZ"}];
let hasMatch = result.filter(r => r.name === "FGH" || r.name === "ABC").length === 2;
if (hasMatch) {
// do logic
}
Or a bit more verbose for clarity:
let result = [{"name": "ABC"},{"name": "CDE"},{"name": "FGH"},{"name": "XYZ"}];
let filteredResult = result.filter(r => r.name === "FGH" || r.name === "ABC");
let hasMatch = filteredResult.length === 2;
if (hasMatch) {
// do logic
}

You can simply create another array with the valid users and filter your array to match each items that are this array.
This can be done using the Array#includes method
const users = [{"name": "ABC"},{"name": "CDE"},{"name": "FGH"},{"name": "XYZ"}];
const validUsers = ["ABC", "FGH", "AnotherUser"];
const matchUsers = users.filter(user => validUsers.includes(user.name))
console.log(matchUsers)

You could count the wanted names.
const
data = [{ name: "ABC" }, { name: "CDE" }, { name: "FGH" }, { name: "XYZ" }],
names = ['ABC', 'FGH'],
result = data.reduce((t, { name }) => t + names.includes(name), 0);
console.log(result);

Try using a named function and pass in the array, key, and one or more values with the rest operator ...values. Use .flatMap() to filter with
[...values].includes(obj[key])
// ["ABC", "XYZ"].includes(obj.name)
and any non-match returns an empty array []. The final return is an array with a sub-array and the length of said sub-array.
const result = [["ABC", "XYZ"], 2]
// result[0][0] = "ABC"
// result[0][1] = "XYZ"
// result[1] = 2
const arr = [{"name": "ABC"},{"name": "CDE"},{"name": "FGH"},{"name": "XYZ"}];
function hasMatch(array, key, ...values) {
const result = array.flatMap((obj, idx) =>
[...values].includes(obj[key]) ? obj : []);
return [result, result.length];
}
console.log(hasMatch(arr, "name", "ABC", "XYZ"));
console.log(hasMatch(arr, "name", "FGH", "IJK", "LMN", "ABC", "XYZ"));

How to format values of the arrays of array as required?

I have the following array which includes arrays of objects.
const arr = [
[
{
"key1": "keyName",
"key2": "test name1"
},
{
"key1": "keyDescription",
"key2": "test description1"
}
],
[
{
"key1": "keyName",
"key2": "test name2"
},
{
"key1": "keyDescription",
"key2": "test description2"
}
]
]
The result which I required is as follows.
result = [
{
"key_name": "test name1",
"key_description": "test description1"
},
{
"key_name": "test name2",
"key_description": "test description2"
}
]
I have tried this using js 'map' and 'find' methods and it gived wrong format.
const res = arr.map(i => i.find(j => j.setting_code === "hotelRate")).map(k => k.setting_value)
I heard that this can be done using 'reduce'. I would be grateful for suggestions. Thanks!

The following solution just uses map and then a forEach loop inside that map to add the [key1]: key2 object pair to each object.
const arr=[[{key1:"keyName",key2:"test name1"},{key1:"keyDescription",key2:"test description1"}],[{key1:"keyName",key2:"test name2"},{key1:"keyDescription",key2:"test description2"}]];
const result = arr.map(el => {
const obj = {};
el.forEach(({key1, key2}) => {
const snakeKey = key1.replace(/[A-Z]/g, letter => `_${letter.toLowerCase()}`);
obj[snakeKey] = key2;
})
return obj;
})
console.log(result);
Edit: As Andreas points out in the comments, this can be written with a reduce method if that is a requirement:
const result = arr.map(el => {
return el.reduce((result, current) => {
const snakeKey = current.key1.replace(/[A-Z]/g, letter => `_${letter.toLowerCase()}`);
result[snakeKey] = current.key2;
return result;
}, {});
})

arr.map(function(item) {
var props = {};
item.forEach(function(keyValue) {
props[keyValue["key1"]] = keyValue["key2"];
});
return props;
});

combining duplicate key's values in JavaScript array

I have an Array that contain some keys/values one of the values is an array I want combining the value of array from all recorded that have same key in my Array.
Below is an Simple Example to demonstrate, I am not able to construct its logic so seeking help in building a logic to it.
[{"somekey":"Some Value Pushed"},{"somekey":"Second Value"}]
I want Result Like,
[{"somekey":["Some Value Pushed","Second Value"]}]

The reduce() function of Array Object in JavaScript can merge any array into a single Object.
I wrote a single-line code to solve this problem.
I updated result with the array.
const arr = [{
somekey: "Some Value Pushed",
},
{
somekey2: "Second Value2",
},
{
somekey: "Some Value Pushed",
},
{
somekey2: "Second Value3",
},
{
somekey3: "",
},
{},
];
const ansObj = arr.reduce(
(prv, cur) => {
Object.entries(cur).forEach(([key, v]) => key in prv ? prv[key].push(v) : (prv[key] = [v]));
return prv;
}, {}
)
const ansArray = Object.entries(ansObj).map(([key, value])=>({[key]:value}));
console.log(ansArray);

You can try something like this:
var array = [{
name: "foo1",
value: "val1"
}, {
name: "foo1",
value: ["val2", "val3"]
}, {
name: "foo2",
value: "val4"
}];
var output = [];
array.forEach(function(item) {
var existing = output.filter(function(v, i) {
return v.name === item.name;
});
if (existing.length) {
var existingIndex = output.indexOf(existing[0]);
output[existingIndex].value = output[existingIndex].value.concat(item.value);
} else {
if (typeof item.value === 'string')
item.value = [item.value];
output.push(item);
}
});
Or, another option using Lodash
function mergeNames (arr) {
return _.chain(arr).groupBy('name').mapValues(function (v) {
return _.chain(v).pluck('value').flattenDeep();
}).value();
}

Maybe something like:
const data = [
{"somekey":"Some Value Pushed"},
{"somekey":"Second Value", "otherkey": 1},
{"otherkey": 2}
];
const merge_and_group = (obj1, obj2) =>
Object.entries(obj2).reduce(
(acc, [key, val]) => {
acc[key] ??= [];
acc[key].push(val);
return acc;
},
obj1
);
const res = data.reduce(merge_and_group, {});
console.log(res);

const arr = [{
"somekey": "Some Value Pushed"
}, {
"somekey2": "Second Value2"
}, {
"somekey": "Some Value Pushed"
}, {
"somekey2": "Second Value3"
}]
const newarr = {}
arr.forEach(obj => {
for (const [key, value] of Object.entries(obj)) {
if (newarr[key]) newarr[key].push(value)
else newarr[key] = [value]
}
})
console.log(newarr)

Array.prototype.reduce() is a possible option.
the reduce() method executes a reducer function which is provided as an input on each element of the array and returning a single output value.
const array = [{"somekey":"Some Value Pushed"},{"somekey":"Second Value"}];
const res = array.reduce((acc, el) => {
const [key, value] = Object.entries(el)[0];
(acc[key] || (acc[key] = [])).push(value);
return acc;
}, {});
console.log(res)

Assuming each element of your array is an object with a single key.
const array = [
{ somekey: "Some Value Pushed" },
{ somekey: "Second Value" },
{ foo: "bar" },
{ foo: "baz" },
{ somekey: "Third Value" },
];
const result = [];
array.forEach(el => {
let [key, value] = Object.entries(el)[0];
for (let el of result) if (key in el) {
el[key].push(value);
return;
}
result.push({ [key]: [value] });
});
console.dir(result);

If your array has only "somekey" as keys then you can use map method as following:
const array = [{"somekey":"Some Value Pushed"},{"somekey":"Second Value"}];
const valuesArray = array.map(obj => obj.somekey);
result = [{"somekey":valuesArray}];
console.log(result)

If your array has other keys along with "somekey" and you like to separate values corresponding to only "somekey" then try the following:
const array = [{"somekey":"Some Value Pushed"},{"somekey":"Second Value"}, {"otherkey":"other Value"}];
const filteredArray = array.filter((obj) => {
return "somekey" in obj
}, []);
const valuesArray = filteredArray.map(obj => obj.somekey);
result = [{"somekey":valuesArray}];
console.log(result)

how to add objects to arrays

I'm trying to construct an array of objects from a set of two different arrays. I'm a little comfussed on where I need to go from here.
I'm creating a unique key value, but the object is going into the array individual.
const startingArray = [
{
key: "description",
value: "my description"
},
{
key: "description2",
value: "my description2"
},
{
key: "description3",
value: "my description3"
},
]
my logic
const k = mystartingArray.reduce((acc, d, count) => {
const name = Object.value(d)[0]
const title = Object.value(d)[1]
const value = {
[name]: title
}
acc.push(value)
return acc
},[])
how I want the Array to look
const finishedArray = [
{
description: "my description",
description2: "my description2,
description3: "my description3,
}
How far am I off?

I think this would be simpler to solve just by using a basic forEach.
let value = {};
startingArray.forEach(obj => {
value[obj.key] = obj.value;
});
const finishedArray = [value];
Or, if you don't want to have a value object:
const finishedArray = [{}];
startingArray.forEach(obj => {
finishedArray[0][obj.key] = obj.value;
});

const finishedArray = [
startingArray.reduce((a, v) => {a[v.key] = v.value; return a}, {})
]

To finish your code:
const startingArray = [
{
key: "description",
value: "my description"
},
{
key: "description2",
value: "my description2"
},
{
key: "description3",
value: "my description3"
},
];
const k = startingArray.reduce((acc, d, count) => {
return [{
...(acc[0] || {}),
[d.key]: d.value
}]
},[])
console.log(k);
However, I think the solution of Rocket Hazmat is more reasonable than this.