Deep-Sort

A handy utility function to sort arrays of objects or dictionaries of objects by property (including nested properties).

Quick Start

Sorting behaviour is the same as Array.sort(). See the /examples directory for some working examples.

Sorting an Array of Objects

You can sort an array of objects based on one of its (nested) properties. Arrays are sorted in place (the original array is mutated) and the result is returned.

const deepSort = require(`deep-sort`);

const myArray = [
	{ id: 1, nested: { time: 111, deeper: { text: `AAA` } } },
	{ id: 2, nested: { time: 222, deeper: { text: `BBB` } } },
	{ id: 3, nested: { time: 333, deeper: { text: `CCC` } } },
];

// Shorthand.
deepSort.array(myArray, `id`);  // Default is order ASC.
deepSort.array(myArray, `id`, `asc`);
deepSort.array(myArray, `id`, `desc`);
deepSort.array(myArray, `nested.time`, `asc`);
deepSort.array(myArray, `nested.deeper.text`, `desc`);
deepSort.array(myArray, `nested.deeper.text`, `desc`, comparatorFunction);

// Longhand (all arguments required).
deepSort(myArray, null, `id`, `asc`);
deepSort(myArray, null, `id`, `asc`, comparatorFunction);

Sorting a Dictionary of Objects

You can sort a dictionary of objects based on one of its (nested) properties. Dictionaries are not mutated, and a new dictionary will be returned.

const deepSort = require(`deep-sort`);

const myDictionary = {
	'key_1nd': { key: `key_1nd`, quantity: 98, nested: { time: 111, deeper: { text: `AAA` } } },
	'key_k8a': { key: `key_k8a`, quantity: 45, nested: { time: 222, deeper: { text: `BBB` } } },
	'key_aj3': { key: `key_aj3`, quantity: 1, nested: { time: 333, deeper: { text: `CCC` } } },
};

// Shorthand.
deepSort.object(myDictionary, `key`, `quantity`);  // Default is order ASC.
deepSort.object(myDictionary, `key`, `quantity`, `asc`);
deepSort.object(myDictionary, `key`, `quantity`, `desc`);
deepSort.object(myDictionary, `key`, `nested.time`, `asc`);
deepSort.object(myDictionary, `key`, `nested.deeper.text`, `desc`);
deepSort.object(myDictionary, `key`, `nested.deeper.text`, `desc`, comparatorFunction);

// Longhand (all arguments required).
deepSort(myDictionary, `key`, `quantity`, `quantity`, `asc`);
deepSort(myDictionary, `key`, `quantity`, `quantity`, `asc`, comparatorFunction);

Custom Comparator Function

If you need more control you can pass a comparator function to the deepSort.custom() method. You must return a numerical value from this function which can be accepted by Array.sort():

• -1 - Sort itemA lower than itemB. (ASC).
• 0 - Leave in place.
• +1 - Sort itemA higher than itemB (DESC).

// Arrays.
deepSort.custom(array, resources => {

	// resources.itemA    -> the next item in the iterable.
	// resources.itemB    -> the next + 1 item in the iterable.
	// resources.iterable -> the input iterable (array).

	return an integer;

});

// Objects.
deepSort.custom(dictionary, `someKeyProperty`, resources => {

	// resources.itemA    -> the next item in the iterable.
	// resources.itemB    -> the next + 1 item in the iterable.
	// resources.iterable -> the input iterable (dictionary).

	return an integer;

});

If you pass a comparator function to deepSort(), deepSort.array() or deepSort.object() you get access to all the input arguments:

function comparator (resources) {

	// resources.propA         -> the next item property in the iterable (specified by sortProperty).
	// resources.propB         -> the next + 1 item property in the iterable (specified by sortProperty).
	// resources.itemA         -> the next item in the iterable.
	// resources.itemB         -> the next + 1 item in the iterable.
	// resources.iterable      -> the input iterable (array or dictionary).
	// resources.keyProperty   -> the input keyProperty (array or dictionary).
	// resources.sortProperty  -> the input sortProperty (array or dictionary).
	// resources.sortDirection -> the input sortDirection (array or dictionary).

	return an integer;

}

API Overview

deepSort(iterable, keyProperty, sortProperty, sortDirection = 'asc', comparator = null)

Sort the given iterable (array or dictionary) with all arguments available.

deepSort.array(array, sortProperty, sortDirection = 'asc', comparator = null)

Sort the given array using the given object path, ordering flag, and optional comparator.

The optional comparator function will be passed the following values (e.g. comparator (resources) { ... }):

• resources.propA
• resources.propB
• resources.itemA
• resources.itemB
• resources.iterable
• resources.keyProperty
• resources.sortProperty
• resources.sortDirection

deepSort.object(object, keyProperty, sortProperty, sortDirection = 'asc', comparator = null)

Sort the given object using the given key property, object path and custom comparator function.

The optional comparator function will be passed the following values (e.g. comparator (resources) { ... }):

• resources.propA
• resources.propB
• resources.itemA
• resources.itemB
• resources.iterable
• resources.keyProperty
• resources.sortProperty
• resources.sortDirection

deepSort.custom(iterable, comparator)

Sort the given iterable using the result of a custom comparator function.

The required comparator function will be passed the following values (e.g. comparator (resources) { ... }):

• resources.itemA
• resources.itemB
• resources.iterable