How group and count elements by lodash - lodash

Question

has data
items = {
0: {id:1,name:'foo'},
1: {id:2,name:'bar'},
2: {id:1,name:'foo'}
};
I wont get counted elements like this
result = {
0: {id:1,name:'foo', count:2},
1: {id:2,name:'bar', count:1}
};
lodash has function _.countBy(items, 'name') it's got {'foo': 2, 'bar':1}, i need id too.

Answer 1

If pure JS approach is acceptable, you can try something like this:
Logiic:
Loop over array and copy the object and add a property count and set it to 0.
Now on every iteration update this count variable.
Using above 2 steps, create a hashMap.
Now loop over hashMap again and convert it back to array.
var items = [{
id: 1,
name: 'foo'
}, {
id: 2,
name: 'bar'
}, {
id: 1,
name: 'foo'
}
];
var temp = items.reduce(function(p,c){
var defaultValue = {
name: c.name,
id: c.id,
count: 0
};
p[c.name] = p[c.name] || defaultValue
p[c.name].count++;
return p;
}, {});
var result = [];
for( var k in temp ){
result.push(temp[k]);
}
console.log(result)