Benchmark: lodash isObject vs typeof vs isObjectLike

HTML Preparation code:

<script src='https://cdnjs.cloudflare.com/ajax/libs/lodash.js/4.17.20/lodash.min.js'></script>

Script Preparation code:

var x = {'this': 'is', 'a': 'test', 'object': 52 }

Tests:

isObject
var y = _.isObject(x)
typeof
var y = (x !== null && typeof(x) === 'object')
isObjectLike
var y = _.isObjectLike(x)

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
isObject
typeof
isObjectLike

Fastest: N/A

Slowest: N/A

Latest run results:

Run details: (Test run date: 19 days ago)

User agent: Mozilla/5.0 (X11; Ubuntu; Linux x86_64; rv:133.0) Gecko/20100101 Firefox/133.0

Browser/OS: Firefox 133 on Ubuntu

View result in a separate tab

Test name	Executions per second
isObject	1364557824.0 Ops/sec
typeof	1648536832.0 Ops/sec
isObjectLike	1690356864.0 Ops/sec

Autogenerated LLM Summary (model llama3.2:3b, generated 2 months ago):

LLMs can make mistakes. Check important info.

Let's break down what is tested in the provided benchmark.

**Benchmark Overview**

The benchmark compares three different approaches to check if an object is a plain JavaScript object (`Object`), an object-like value (with `typeof` checking for `'object'`) or an instance of a custom object type defined by Lodash (`_.isObject()`).

**Options Compared**

1. **_.isObject(x)**: This function checks if the input `x` has all the properties and no additional ones, which is similar to a strict equality check using `===`. It's useful when you want to ensure that an object doesn't have any unexpected properties or values.
2. **`typeof x === 'object'`**: This expression uses the `typeof` operator to check if the input `x` has a value type of `'object'`. However, this approach can return false positives for custom objects with a specific prototype chain.
3. **_.isObjectLike(x)**: This function is similar to _.isObject(), but it allows for some minor deviations in object definitions, making it more lenient than the strict equality check.

**Pros and Cons**

1. **_.isObject()`**:
	* Pros: Provides a strict equality check, ensuring no unexpected properties or values.
	* Cons: Can be slower due to its more complex implementation.
2. **`typeof x === 'object'`**:
	* Pros: Fast and lightweight, as it only requires a simple type check.
	* Cons: May return false positives for custom objects with specific prototypes.
3. **_.isObjectLike()`**:
	* Pros: More lenient than _.isObject(), allowing for some minor deviations in object definitions.
	* Cons: May return false negatives if the input is not an object-like value.

**Lodash Library**

The `lodash` library provides a set of utility functions, including `isObject()`, which can be used to simplify code and improve performance. In this benchmark, Lodash's implementation of `isObject()` is compared to the simple `typeof x === 'object'` approach.

**JavaScript Features**

This benchmark does not explicitly test any special JavaScript features or syntax. However, it does rely on some fundamental concepts, such as:

* Object equality checks
* Prototype chains
* Type coercion using `typeof`

The benchmark assumes that the input `x` is a valid JavaScript object (or an object-like value). If `x` were not a valid object, the results would be undefined or incorrect.

**Alternatives**

Other alternatives for checking if an object is a plain JavaScript object could include:

* Using a library like `is-object` which provides a more strict equality check
* Implementing your own custom equality check function
* Using a testing framework like Jest or Mocha, which provide built-in assertion functions for objects.

However, the use of Lodash's `isObject()` and `isObjectLike()` functions is a common pattern in JavaScript development, making this benchmark particularly relevant to developers who are familiar with these utility functions.

Related benchmarks:

lodash isObject vs typeof vs isObjectLike (version: 0)

Comparing performance of: isObject vs typeof vs isObjectLike

Created: 2 years ago by: Guest

Jump to the latest result

isObject

typeof

isObjectLike

Suite status: <idle, ready to run>

Experimental features:

Fastest: N/A

Slowest: N/A

Autogenerated LLM Summary (model llama3.2:3b, generated 2 months ago):