Benchmark: Object Assign vs Manual Assign

Tests:

Object Assign
function hello(v) { Object.assign(v, {a:1,b:2,c:3,d:4}) } for (let i = 0; i < 100000; i++) { hello({}) }
Manual Assign
function hello(v) { v.a = 1 v.b = 2 v.c = 3 v.d = 4 } for (let i = 0; i < 100000; i++) { hello({}) }

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
Object Assign
Manual Assign

Fastest: N/A

Slowest: N/A

Latest run results:

Run details: (Test run date: 6 months ago)

User agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/141.0.0.0 Safari/537.36

Browser/OS: Chrome 141 on Windows

View result in a separate tab

Test name	Executions per second
Object Assign	657.3 Ops/sec
Manual Assign	34641.1 Ops/sec

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

LLMs can make mistakes. Check important info.

Let's break down the provided benchmark definition and explain what is being tested.

The main objective of this benchmark is to compare two approaches for assigning properties to an object in JavaScript:

1. **Object Assign**: This approach uses the `Object.assign()` method to assign properties to an object.
2. **Manual Assign**: This approach assigns properties directly to the object without using a method.

Let's dive into the pros and cons of each approach:

**Object Assign:**

Pros:

* Efficient and concise way to assign multiple properties at once.
* Well-supported in modern JavaScript engines.
* Easy to read and maintain.

Cons:

* May have performance overhead due to the use of a built-in method.
* Some older browsers or environments might not support `Object.assign()`.

**Manual Assign:**

Pros:

* Can be faster for small objects, as it avoids the overhead of a built-in method.
* Well-supported in older JavaScript engines and browsers.
* Easy to implement.

Cons:

* Requires multiple lines of code for each property assignment.
* Less readable and maintainable than using `Object.assign()`.

Other considerations:

* The benchmark uses a simple object literal (`{}`) as the target object. In real-world scenarios, objects can be more complex, with nested properties or arrays.
* Both approaches use a loop to execute the assignment code 100,000 times. This helps to eliminate other factors that might affect performance.

**Library and Special JS features:**

There are no libraries used in this benchmark. However, it's worth noting that `Object.assign()` is a built-in method in JavaScript, which means it doesn't require any external libraries or modules.

**Other alternatives:**

If you wanted to explore alternative approaches, here are some options:

1. **Property Iteration**: Instead of using `Object.assign()`, you could use the `for...in` loop to iterate over the object's properties and assign each one individually.
2. **Array Destructuring**: Modern JavaScript engines support array destructuring, which allows you to assign multiple values from an array or object into individual variables.
3. **Spread Operator**: The spread operator (`{...}`) can be used to create a new object by copying the properties of another object.

Here's some sample code for each alternative:
```javascript
// Property Iteration
for (let key in obj) {
  obj[key] = value;
}

// Array Destructuring
const [a, b, c, d] = [1, 2, 3, 4];
obj.a = a;
obj.b = b;
obj.c = c;
obj.d = d;

// Spread Operator
const newObj = { ...obj };
newObj.a = 1;
newObj.b = 2;
newObj.c = 3;
newObj.d = 4;
```
These alternatives might offer different trade-offs in terms of performance, readability, and maintainability. However, they are not part of the original benchmark definition, which compares `Object.assign()` with manual assignment.

Related benchmarks:

Object Assign vs Manual Assign (version: 0)

Comparing performance of: Object Assign vs Manual Assign

Created: 5 years ago by: Guest

Jump to the latest result

Object Assign

Manual Assign

Suite status: <idle, ready to run>

Fastest: N/A

Slowest: N/A

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