Lodash _.stubArray() Method

What You’ll Learn

By the end of this tutorial, you’ll use Lodash’s _.stubArray() as a small factory that returns fresh empty arrays—ideal for defaults, fallbacks, and functional callbacks.

What Is _.stubArray()?

_.stubArray is a function with no parameters that returns an empty array. Call it as _.stubArray() when you need [] right now, or pass _.stubArray (without parentheses) when another API wants a function that produces empty arrays—similar to writing () => [].

It sits in Lodash’s stub helper family alongside _.stubFalse() and _.constant()—small building blocks for readable functional code.

📝 Syntax

Invoke with no arguments:

_.stubArray()

Syntax Rules

• _.stubArray — the function reference (pass to callbacks).
• _.stubArray() — call it to get [] immediately.
• Fresh arrays — each call returns a new empty array instance.
• Zero args — ignores any arguments if callers pass them anyway.
• Length zero — _.stubArray().length === 0.

import stubArray from "lodash/stubArray";



stubArray();

// []

Examples Gallery

Practical _.stubArray() patterns with copy-ready code, sample output, and interactive Try It Yourself labs.

const empty = _.stubArray();



console.log(empty);

console.log(Array.isArray(empty));

console.log(empty.length);

// []

// true

// 0

[]

true

0

const a = _.stubArray();

const b = _.stubArray();



a.push(1);



console.log(a);

console.log(b);

console.log(a === b);

// [1]

// []

// false

[1]

[]

false

function processItems(items = _.stubArray()) {

  return items.length;

}



console.log(processItems());

console.log(processItems([1, 2, 3]));

// 0

// 3

0

3

function mergeArrays(

  array1 = _.stubArray(),

  array2 = _.stubArray()

) {

  return array1.concat(array2);

}



console.log(mergeArrays([1, 2, 3]));

console.log(mergeArrays());

// [1, 2, 3]

// []

[1, 2, 3]

[]

function fetchTags(apiResult) {

  const tags = apiResult && apiResult.tags;

  return tags || _.stubArray();

}



console.log(fetchTags({ tags: ["js", "lodash"] }));

console.log(fetchTags(null));

// ["js", "lodash"]

// []

["js", "lodash"]

[]

// Immediate empty array

console.log(_.stubArray());



// ES default — also common

function fn(x = []) { return x; }



// Same reference every call — caution if mutating

const shared = _.constant([]);

console.log(shared() === shared());



// Arrow equivalent of stubArray

console.log((() => [])() instanceof Array);

// true for all [] producers

[]

true

true

📝 Notes

• Returns a real array—not an “array-like” plain object.
• Each _.stubArray() call creates a separate []—unlike _.constant([]).
• Pass _.stubArray without parentheses when an API expects a zero-arg producer function.
• return items || _.stubArray() treats empty array as truthy—use nullish coalescing if [] should be preserved.
• Part of the stub helper family—next: _.stubFalse().
• Previous in the series: _.runInContext().

💡 Best Practices