Benchmark: my isEqual - MeasureThat.net

HTML Preparation code:

<script src="https://cdn.jsdelivr.net/npm/lodash@4.17.4/lodash.min.js"></script>
<script>
  function isEqual(a, b) {
    var aProps = Object.getOwnPropertyNames(a)
      , bProps = Object.getOwnPropertyNames(b);

    if (aProps.length != bProps.length) {
      return false;
    }

    for (var i = 0; i < aProps.length; i++) {
      var propName = aProps[i];
      if (typeof(a[propName]) === 'object' && a[propName] !== null) {
        if (!isEqual(a[propName], b[propName])) {
          return false
        }
      } else if (Number.isNaN(a[propName])) {
        if (!Number.isNaN(b[propName])) {
          return false
        }
      } else if (a[propName] !== b[propName]) {
        return false;
      }
    }
    return true;
  }
</script>

Script Preparation code:

// 1 level deep
window.foo1 = { a: 1, b: 2, c: { a: 1, b: 2, c: { a: 1, b: 2 } } };
window.bar1 = { a: 1, b: 3, c: { a: 1, b: 2, c: { a: 1, b: 2 } } };

// 2 levels deep
window.foo2 = { a: 1, b: 2, c: { a: 1, b: 2, c: { a: 1, b: 2 } } };
window.bar2 = { a: 1, b: 2, c: { a: 1, b: 3, c: { a: 1, b: 2 } } };

// 3 levels deep
window.foo3 = { a: 1, b: 2, c: { a: 1, b: 2, c: { a: 1, b: 2 } } };
window.bar3 = { a: 1, b: 2, c: { a: 1, b: 2, c: { a: 1, b: 4 } } };

Tests:

_.isEqual Level 1
_.isEqual(window.foo1, window.bar1)
isEqual Level 1
isEqual(window.foo1, window.bar1)
_.isEqual Level 2
_.isEqual(window.foo2, window.bar2)
isEqual Level 2
isEqual(window.foo2, window.bar2)
_.isEqual Level 3
_.isEqual(window.foo3, window.bar3)
isEqual Level 3
isEqual(window.foo3, window.bar3)

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
_.isEqual Level 1
isEqual Level 1
_.isEqual Level 2
isEqual Level 2
_.isEqual Level 3
isEqual Level 3

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_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/86.0.4240.111 Safari/537.36

Browser/OS: Chrome 86 on Mac OS X 10.15.7

View result in a separate tab

Test name	Executions per second
_.isEqual Level 1	645540.8 Ops/sec
isEqual Level 1	1411980.9 Ops/sec
_.isEqual Level 2	411203.7 Ops/sec
isEqual Level 2	1178556.0 Ops/sec
_.isEqual Level 3	321525.1 Ops/sec
isEqual Level 3	1007631.3 Ops/sec

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

LLMs can make mistakes. Check important info.

I'll break down the provided benchmark and explain what's being tested, compared options, pros and cons of each approach, library usage, and special JavaScript features.

**Benchmark Overview**

The benchmark tests the performance of two equality functions: `isEqual` (from Lodash) and a custom implementation. The test cases create complex objects with nested properties to exercise the equality function.

**Test Cases**

There are four test cases:

1. `_.isEqual(window.foo1, window.bar1)` (Level 1)
2. `_.isEqual(window.foo2, window.bar2)` (Level 2)
3. `_.isEqual(window.foo3, window.bar3)` (Level 3)

These tests compare two objects at each level of nesting:

* Level 1: Two objects with different properties
* Level 2: Two objects with similar but not identical properties
* Level 3: Two objects with identical properties

**Custom Implementation**

The custom `isEqual` function is implemented using recursion, which makes it easy to see how the code compares the two input objects. The implementation checks for:

* Object property names (using `Object.getOwnPropertyNames`)
* Property types and values
* Object structure (nested objects)

While the custom implementation works, it may not be as efficient as the Lodash version.

**Lodash Library**

The benchmark uses the Lodash library to provide a pre-existing implementation of the `isEqual` function. Lodash is a popular utility library that provides various functions for data manipulation and analysis.

**Comparison Options**

There are two main comparison options:

1. **_.isEqual (Lodash)**: The optimized, pre-built equality function from Lodash.
2. **Custom Implementation**: A custom implementation of the `isEqual` function using recursion.

**Pros and Cons**

* _.isEqual:
	+ Pros:
		- Optimized for performance
		- Well-tested and maintained
	+ Cons:
		- Not easily modifiable (unless you're a Lodash maintainer)
		- May not be suitable for all use cases (e.g., specific industry requirements)
* Custom Implementation:
	+ Pros:
		- Highly customizable
		- Easy to understand and maintain
	+ Cons:
		- May be slower than the optimized _.isEqual implementation

**Special JavaScript Features**

There are no special JavaScript features used in this benchmark, but some minor optimizations might be applicable:

* Using `Object.keys()` instead of `Object.getOwnPropertyNames` for a small performance boost.
* Considering using a library like `fast-json-stamp` for faster JSON serialization.

Overall, the benchmark provides a clear comparison between two equality functions: an optimized Lodash implementation and a custom recursive implementation. This allows users to choose the best fit for their specific use case, considering factors such as performance, customization options, and maintainability.

Related benchmarks:

my isEqual (version: 0)

Test on isEqual performance

Comparing performance of: _.isEqual Level 1 vs isEqual Level 1 vs _.isEqual Level 2 vs isEqual Level 2 vs _.isEqual Level 3 vs isEqual Level 3

Created: 4 years ago by: Guest

Jump to the latest result

_.isEqual Level 1

isEqual Level 1

_.isEqual Level 2

isEqual Level 2

_.isEqual Level 3

isEqual Level 3

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):