group-by-with-sum

Collapses an array of objects at the specified object properties

``bash
npm install group-by-with-sum
`

`js
const groupBy = require('group-by-with-sum');

const arr = [
{ name: 'Vasya', who: 'man', money: 100 },
{ name: 'Vasya', who: 'man', money: 263 },
{ name: 'Kolya', who: 'man', money: 98 },
{ name: 'Katya', who: 'woman', money: 290 },
{ name: 'Olya', who: 'woman', money: 5 }
];

const whoWithMoney = groupBy(arr, 'who', 'money');
/* [
{ who: 'man', money: 461 },
{ who: 'woman', money: 295 }
]
*/

const whoNameWithMoney = groupBy(arr, 'who,name', 'money');
/* [
{ who: 'man', name: 'Vasay', money: 363 },
{ who: 'man', name: 'Kolya', money: 98 },
{ who: 'woman', name: 'Katya', money: 290 },
{ who: 'woman', name: 'Olya', money: 5 }
]
*/
`

#### Without summary props
`js
const who = groupBy(arr, 'who');
// [{ who: 'man', who: 'woman' }]
`

$3

`js
const badArray = [
{ name: 'a', who: 'people', money: '10' },
{ name: 'b', who: 'people', money: '15' },
{ name: 'b', who: 'animals', money: '0' }
];

const result = groupBy(badArray, 'who', 'money');
/* [
{ who: 'people', money: 25 },
{ who: 'animals', money: 0 }
]
*/
`

$3

`js
const badArray = [
{ name: 'a', who: 'people', money: '10' },
{ name: 'b', who: 'people' },
{ name: 'b', who: 'animals', money: '0' }
];

const result = groupBy(badArray, 'who', 'money');
/* [
{ who: 'people', money: 10 },
{ who: 'animals', money: 0 }
]
*/
`

$3

`js
const badArray = [
{ name: 'a', who: 'people', money: '10' },
{ name: 'b', money: '16' },
{ name: 'b', who: 'animals', money: '0' }
];

const result = groupBy(badArray, 'who', 'money');
/* [
{ who: 'people', money: 10 },
{ who: undefined, money: 16 },
{ who: 'animals', money: 0 }
]
*/
`

$3

`js
const arr = [
{
who: { role: 'dev', access: [ 'dev' ] },
profile: { name: 'vasya', email: 'vasyq@domen.com' },
commits: 140
},
{
who: { role: 'dev', access: [ 'dev' ] },
profile: { name: 'kolya', email: 'kolya@domen.com' },
commits: 156
},
{
who: { role: 'main', access: [ 'dev', 'master' ] },
profile: { name: 'kolya', email: 'kolya@domen.com' },
commits: 11
},
{
who: { role: 'main', access: [ 'dev', 'master' ] },
profile: { name: 'gg', email: 'gg@domen.com' },
commits: 260
}
];

const result = groupBy(arr, 'profile', 'commits');
/* [
{
profile: { name: 'vasya', email: 'vasyq@domen.com' },
commits: 140
},
{
profile: { name: 'kolya', email: 'kolya@domen.com' },
commits: 167
},
{
profile: { name: 'gg', email: 'gg@domen.com' },
commits: 260
}
]
*/
`

$3

`js
const fn = (grouped) => {
return grouped.profile.email;
};

const result = groupBy(arr, 'profile', 'commits', fn);
/* [
{
profile: { name: 'vasya', email: 'vasyq@domen.com' },
commits: 140
},
{
profile: { name: 'kolya', email: 'kolya@domen.com' },
commits: 167
},
{
profile: { name: 'gg', email: 'gg@domen.com' },
commits: 260
}
]
*/

``