Benchmark: Object.assign vs spread operator irek

Tests:

Object.assign
var params = { b:"hello", c: true, d:7 }; var other = Object.assign({ a: 2 }, params);
spread operator
var params = { b:"hello", c: true, d:7 }; var other = { a: 2, ...params };

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
Object.assign
spread operator

Fastest: N/A

Slowest: N/A

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

LLMs can make mistakes. Check important info.

Let's break down the provided benchmark definition and test cases to understand what is being tested.

**Benchmark Definition:**

The benchmark definition provides two different approaches for merging objects in JavaScript:

1. **Object.assign():** This method takes two or more source objects and merges them into a new object, optionally initializing properties of the target object with values from the source objects.
2. **Spread Operator (...):** This operator allows you to expand an array or object into individual elements or properties.

**Options Compared:**

The benchmark compares the performance of these two approaches:

1. `Object.assign()`
2. Spread Operator (`...`)

**Pros and Cons:**

* **Object.assign():**
	+ Pros:
		- Widely supported by most browsers.
		- Can be used to merge objects in a declarative way.
	+ Cons:
		- Can be slower than the spread operator due to its method call overhead.
		- May incur additional overhead if dealing with large objects or arrays.
* **Spread Operator:**
	+ Pros:
		- Often faster than `Object.assign()` due to its syntax and optimization by modern browsers.
		- More concise and readable code.
	+ Cons:
		- Limited browser support (older versions) may not execute correctly.
		- May require extra semicolons or newline characters in some cases.

**Library Usage:**

There is no library usage in this benchmark definition. The tests focus solely on the comparison of `Object.assign()` and the spread operator.

**Special JS Features/Syntax:**

The test does not utilize any special JavaScript features or syntax, such as async/await, generators, or modern ECMAScript proposals.

**Other Alternatives:**

If you were to write this benchmark yourself, you might consider using other alternatives for merging objects or arrays in JavaScript, such as:

1. **Object.create()**: This method creates a new object and sets its prototype to the specified value.
2. **Array.prototype.slice() / Array.prototype.concat()**: These methods can be used to merge two arrays into one.

For object mergers, you could also consider using libraries like `lodash.merge()` or `merge-deep`.

Keep in mind that these alternatives might have different performance characteristics and syntax usage compared to `Object.assign()` and the spread operator.

Latest run results:

Run details: (Test run date: 5 years ago)

User agent: Mozilla/5.0 (Linux; Android 9; A0001 Build/PQ3A.190801.002) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/74.0.3729.157 Mobile Safari/537.36 OPR/53.1.2569.142848

Browser/OS: Opera Mobile 53 on Android

View result in a separate tab

Test name	Executions per second
Object.assign	586490.1 Ops/sec
spread operator	309917.3 Ops/sec

Related benchmarks:

Object.assign vs spread operator irek (version: 0)

Comparing performance of: Object.assign vs spread operator

Created: 5 years ago by: Guest

Jump to the latest result

Object.assign

spread operator

Suite status: <idle, ready to run>

Experimental features:

Fastest: N/A

Slowest: N/A

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