Benchmark: Lodash.isEqual vs JSON.stringify Equality Comparison for Plain Objects

HTML Preparation code:

<script src="https://cdn.jsdelivr.net/npm/lodash@4.17.4/lodash.min.js"></script>

Script Preparation code:

window.foo = {type: 'cat', age: 11, color: 'black'}
window.bar = {type: 'dog', age: 9, color: 'brown'}

Tests:

_.isEqual
_.isEqual(window.foo, window.bar)
JSON.stringify
JSON.stringify(window.foo) === JSON.stringify(window.bar);

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
_.isEqual
JSON.stringify

Fastest: N/A

Slowest: N/A

Latest run results:

Run details: (Test run date: 4 years ago)

User agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.15; rv:77.0) Gecko/20100101 Firefox/77.0

Browser/OS: Firefox 77 on Mac OS X 10.15

View result in a separate tab

Test name	Executions per second
_.isEqual	654424.6 Ops/sec
JSON.stringify	756272.3 Ops/sec

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

LLMs can make mistakes. Check important info.

Let's dive into the explanation of the provided benchmark.

**Benchmark Definition**

The benchmark is designed to compare the performance of two equality comparison functions: Lodash's `isEqual` and a simple string comparison using `JSON.stringify`.

The script preparation code creates two objects, `window.foo` and `window.bar`, with similar properties. The difference lies in the value of the `color` property, which is `'black'` for `foo` and `'brown'` for `bar`. This will cause `isEqual` to produce a false positive result.

**Options Compared**

The two options being compared are:

1. **Lodash's `isEqual`**: A functional equality comparison function that recursively checks if the properties and values of two objects are equal.
2. **Simple string comparison using `JSON.stringify`**: A naive approach that converts both objects to strings using `JSON.stringify` and compares them.

**Pros and Cons**

**Lodash's `isEqual`:**

Pros:

* More accurate results, as it checks for deep equality between objects
* Handles nested objects and arrays correctly
* Less prone to false positives due to differences in object representation

Cons:

* May be slower than the simple string comparison approach
* Requires Lodash library to be loaded

**Simple String Comparison using `JSON.stringify`:**

Pros:

* Very fast, as it only requires comparing strings
* Does not require any additional libraries

Cons:

* May produce false positives due to differences in object representation
* Not suitable for objects with nested structures or arrays

**Other Considerations**

The benchmark does not take into account the size of the input objects. If the objects are very large, Lodash's `isEqual` may still be slower than the simple string comparison approach.

**Library Used: Lodash**

Lodash is a popular JavaScript utility library that provides a wide range of functional programming helpers, including equality checks like `isEqual`. In this benchmark, Lodash is used to provide a more accurate and efficient way to compare objects.

**Special JS Feature/Syntax**

There are no special JavaScript features or syntaxes being tested in this benchmark. The focus is solely on comparing the performance of two different equality comparison approaches.

**Alternatives**

Other alternatives for equality comparison in JavaScript include:

* **Object.keys() and `===`**: A simple approach that compares objects by checking if their properties have the same keys and values.
* **ES6 Object.entries() and `===`**: Another simple approach that uses `Object.entries()` to get an array of key-value pairs and then compares them using `===`.
* **JSON.stringify() with a custom comparison function**: A more advanced approach that allows for customizing the comparison logic, but still may not be as efficient as Lodash's `isEqual`.

Note that these alternatives may have trade-offs in terms of accuracy, performance, or ease of use, and should be evaluated on a case-by-case basis.

Related benchmarks:

Lodash.isEqual vs JSON.stringify Equality Comparison for Plain Objects (version: 0)

Test on isEqual performance for plain objects

Comparing performance of: _.isEqual vs JSON.stringify

Created: 5 years ago by: Guest

Jump to the latest result

_.isEqual

JSON.stringify

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):