Benchmark: spread vs assign 2

Script Preparation code:

var obj1 = {}
var obj2 = {}
var obj3 = {}
var obj4 = {}
var obj5 = {}
var obj6 = {}
var obj7 = {}
var obj8 = {}
var obj9 = {}
var obj10 = {}

;[...Array(100).keys()].forEach(() => {
	obj1[Math.random()] = Math.random()
    obj2[Math.random()] = Math.random()
    obj3[Math.random()] = Math.random()
    obj4[Math.random()] = Math.random()
    obj5[Math.random()] = Math.random()
    obj6[Math.random()] = Math.random()
    obj7[Math.random()] = Math.random()
    obj8[Math.random()] = Math.random()
    obj9[Math.random()] = Math.random()
    obj10[Math.random()] = Math.random()
})

Tests:

spread
var spreadObj = { ...obj1, ...obj2, ...obj3, ...obj4, ...obj5, ...obj6, ...obj7, ...obj8, ...obj9, ...obj10, }
assign
var assignObj = Object.assign({}, obj1, obj2, obj3, obj4, obj5, obj6, obj7, obj8, obj9, obj10)

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:

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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 and explain what's being tested.

**Benchmark Definition**

The benchmark measures the performance difference between two ways of creating objects with spread operators:

1. **Spread operator (`...`)**: This syntax is used to create a new object by spreading the properties of an existing object.
2. **Assignment (`Object.assign()`)**: This method is used to merge multiple objects into one.

**Options Compared**

The benchmark compares these two approaches for creating objects with spread operators:

* `spreadObj`: Creates an object using the spread operator, where each property from `obj1`, `obj2`, ..., `obj10` is copied and added to the new object.
* `assignObj`: Creates an object by assigning multiple objects using the `Object.assign()` method.

**Pros and Cons**

**Spread Operator (`...`)**

Pros:

* Concise and readable syntax
* Can be used with object destructuring (e.g., `{ [key] } = obj`)
* Less memory overhead compared to `Object.assign()`

Cons:

* May not be compatible with older browsers or environments that don't support the spread operator
* Can lead to unexpected behavior if not used carefully (e.g., when dealing with arrays and objects)

**Assignment (`Object.assign()`)**

Pros:

* Widely supported across modern browsers and environments
* Allows for more control over merging properties (e.g., specifying an empty object as the target)
* Can be used with functions that take multiple arguments

Cons:

* More verbose syntax compared to the spread operator
* May require more memory overhead due to the creation of a new object

**Library and Purpose**

In this benchmark, `Object.assign()` is used from the built-in JavaScript `Object` prototype. This library provides a standard way to merge objects into one.

**Special JS Features/Syntax**

The benchmark uses the spread operator (`...`) which is a relatively recent addition to JavaScript (introduced in ES6). It allows for more concise object creation and merging, but may not be supported in older browsers or environments.

**Other Alternatives**

If you want to explore other alternatives, consider using:

* `Object.assign()` with optional parameters (e.g., `{ target: {}, ...obj }`)
* `Object.create()` with the spread operator (`Object.create(obj).properties = obj.properties;`)
* Library functions like Lodash's `_.merge()` or Ramda's `R.merge()`

Keep in mind that the choice of implementation depends on your specific use case, performance requirements, and compatibility concerns.

Related benchmarks:

spread vs assign 2 (version: 0)

Comparing performance of: spread vs assign

Created: 2 years ago by: Registered User

Jump to the latest result

spread

assign

Suite status: <idle, ready to run>

Fastest: N/A

Slowest: N/A

No previous run results

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