lodash - convert object map to array and sort by key

Question

I need to convert an object map (server response) to an array and order this by the object's key.

Given:

var ppl = {
    1: { name: 'Fred', age: 31 },
    0: { name: 'Alice', age: 33 },
    3: { name: 'Frank', age: 34 },
    2: { name: 'Mary', age: 36 }
}

console.log(ppl);

It appears that the object when created is sorted by the key, the console shows this:

{
    0: { name: 'Alice', age: 33 }
    1: { name: 'Fred', age: 31 }
    2: { name: 'Mary', age: 36 }
    3: { name: 'Frank', age: 34 }
}

Then I use lodash to convert to an array like this:

var arr = _.toArray(ppl);
console.log(arr)

1. I don't think the order of the initial object map is guaranteed, is that correct?
2. How can I ensure the array order is based on the object map's keys?

Answer 1

This is easy to do with a the _.chain() method:

var ppl = {
    1: { name: 'Fred', age: 31 },
    0: { name: 'Alice', age: 33 },
    3: { name: 'Frank', age: 34 },
    2: { name: 'Mary', age: 36 }
};

const output = _.chain(ppl)
  .toArray()
  .sortBy()
  .value();
  
console.log(output);

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