Order By custom order in object inside property

Question

I need to sort an array of objects by a property of a sub-object:

foo = [
  {
    bar: {
      order: "hello" 
    } 
  },
  {
    bar: {
      order: "something" 
    } 
  },
  {
    bar: {
      order: "else" 
    } 
  },
]

If I want the order of the foo objects to based on a custom order (not alphabetical!) set by order values like

{ "something": 1, "hello": 2, "else": 3 }

with something like _orderBy(foo, indexOfMyCustomOrder, 'desc'), how can I achieve this? Or do I need to separate this logic into two functions?

Answer 1

Define indexOfMyCustomOrder as follows:

const indexOfMyCustomOrder = o => order[o.bar.order];

... where the order variable should be the object that defines the sequence for each possible value of the order property.

See snippet:

const foo = [{bar:{order:"hello"}},{bar:{order: "something"}},{bar:{order:"else"}}];
const order = { "something": 1, "hello": 2, "else": 3 };

const result = _.orderBy(foo, o => order[o.bar.order]);

console.log(result);

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