Benchmark: testik228 - MeasureThat.net

Tests:

spread
let t = {}; for(i=0; i<100; i++){ const q = {[(Math.random() + 1).toString(36).substring(7)]: (Math.random() + 1).toString(36).substring(7)} t = { ...t, ...q } } console.log(t)
assign
let t = {}; for(i=0; i<100; i++){ const q = {[(Math.random() + 1).toString(36).substring(7)]: (Math.random() + 1).toString(36).substring(7)} Object.assign(t, q); } console.log(t)

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
spread
assign

Fastest: N/A

Slowest: N/A

Latest run results:

Run details: (Test run date: 2 years ago)

User agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/119.0.0.0 Safari/537.36

Browser/OS: Chrome 119 on Mac OS X 10.15.7

View result in a separate tab

Test name	Executions per second
spread	1370.6 Ops/sec
assign	5112.6 Ops/sec

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

LLMs can make mistakes. Check important info.

I'll do my best to break down the provided benchmark JSON and explain what's being tested, compared options, pros and cons, library usage, and special JS features.

**Benchmark Overview**

The provided JSON represents two individual test cases, "spread" and "assign", which measure the performance of JavaScript's spread operator (`...`) versus `Object.assign()` for creating a deep copy of an object. The benchmark is designed to simulate 100 iterations of this process, with random object properties added at each iteration.

**Test Cases**

1. **Spread Operator ("spread")**
	* Benchmark Definition: The script creates an empty object `t` and then uses a `for` loop to iterate 100 times, adding new properties to the object using the spread operator (`...`) to merge with the existing object.
	* Pros:
		+ More concise and expressive way of creating deep copies of objects.
		+ Can handle nested objects more elegantly than `Object.assign()`.
	* Cons:
		+ May be slower due to the overhead of parsing the `...` operator.
2. **Object.assign() ("assign")**
	* Benchmark Definition: The script creates an empty object `t` and then uses a `for` loop to iterate 100 times, adding new properties to the object using `Object.assign()` to merge with the existing object.
	* Pros:
		+ Well-established, widely supported, and efficient way of creating deep copies of objects.
		+ Less overhead than the spread operator due to the simplicity of the method call.
	* Cons:
		+ May be less readable or maintainable compared to the spread operator.

**Library Usage**

In both test cases, no explicit libraries are used beyond what's built-in to JavaScript (e.g., `Object.assign()`).

**Special JS Features**

The benchmark uses a feature that's not commonly discussed: **Symbol Properties**. In the Benchmark Definition, you'll notice the use of `[(Math.random() + 1).toString(36).substring(7)]` as property names. These are generated using a cryptographically secure pseudorandom number generator to create unique symbol properties. This feature is used to simulate nested object structures and add more complexity to the benchmark.

**Other Alternatives**

While not explicitly mentioned, other ways to achieve similar results in this benchmark might include:

* Using `Array.prototype.reduce()` instead of `for` loops.
* Employing a custom implementation using recursion or bitwise operations to create the deep copies.
* Utilizing libraries like Lodash's `cloneDeep()` function for creating deep copies.

However, these alternatives would likely deviate from the original intent of measuring JavaScript's spread operator and `Object.assign()` performance.

Related benchmarks:

testik228 (version: 0)

Comparing performance of: spread vs assign

Created: 2 years ago by: Guest

Jump to the latest result

spread

assign

Suite status: <idle, ready to run>

Fastest: N/A

Slowest: N/A

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