Benchmark: Test method Object

Tests:

Object add new item
const obj = { one: 'val 1' } obj["two"] = "val 2" obj["three"] = "val 3" obj["four"] = "val 4"
Object spread
let obj = { one: 'val 1' } obj = {...obj, two: 'val 2', three: 'val 3', four: 'val 4'}

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
Object add new item
Object spread

Fastest: N/A

Slowest: N/A

Autogenerated LLM Summary (model llama3.2:3b, generated 26 days ago):

LLMs can make mistakes. Check important info.

I'd be happy to explain the benchmark and its test cases.

The provided JSON represents a set of JavaScript microbenchmarks on the MeasureThat.net website. The benchmarks are designed to measure the performance of different approaches for adding new items to an object in JavaScript.

**Benchmark Definition**

The `Benchmark Definition` is an optional field that provides additional context about the benchmark. In this case, it's not present, so we'll focus on the individual test cases.

**Test Cases**

There are two test cases:

1. **Object add new item**

This test case uses the following JavaScript code:
```javascript
const obj = { one: 'val 1' }
obj['two'] = 'val 2'
obj['three'] = 'val 3'
obj['four'] = 'val 4'
```
This code creates an object `obj` with a single property `one`, and then adds four new properties (`two`, `three`, and `four`) using bracket notation.

**Test Case: Object spread**

This test case uses the following JavaScript code:
```javascript
let obj = { one: 'val 1' }
obj = {...obj, two: 'val 2', three: 'val 3', four: 'val 4'}
```
This code creates an object `obj` with a single property `one`, and then uses the spread operator to create a new object with the original properties of `obj` plus three additional properties (`two`, `three`, and `four`) using object literal syntax.

**Options Compared**

The two test cases compare two different approaches for adding new items to an object:

1. **Bracket notation**: The first test case uses bracket notation (`obj['two'] = 'val 2'`) to add new properties to the object.
2. **Object spread operator**: The second test case uses the spread operator (`{...obj, two: 'val 2', three: 'val 3', four: 'val 4'}`) to create a new object with additional properties.

**Pros and Cons**

Here are some pros and cons of each approach:

* **Bracket notation**:
	+ Pros: Can be used to dynamically add or remove properties from an object.
	+ Cons: May have performance overhead due to the use of bracket notation, which can lead to slower execution times compared to other approaches.
* **Object spread operator**:
	+ Pros: Provides a concise and readable way to create new objects with additional properties.
	+ Cons: May not be supported in older browsers or environments, and may have performance implications depending on the complexity of the object being spread.

**Library**

Neither test case uses any external libraries. The code is self-contained and relies only on built-in JavaScript features.

**Special JS Feature/ Syntax**

There are no special JavaScript features or syntax used in these test cases. However, it's worth noting that the use of bracket notation and the spread operator may have been introduced in more recent versions of JavaScript (ECMAScript 2015 and later).

**Other Alternatives**

If you're interested in benchmarking other approaches for adding new items to an object, some alternatives include:

* Using `Object.assign()` or `Array.prototype.push()` to add properties or elements to an object.
* Using a library like Lodash's `assignIn()` function to dynamically add or remove properties from an object.
* Implementing a custom function for adding properties to an object using a loop or recursion.

Keep in mind that the performance implications of these alternatives may vary depending on the specific use case and environment.

Latest run results:

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

User agent: Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/70.0.3538.77 Safari/537.36

Browser/OS: Chrome 70 on Linux

View result in a separate tab

Test name	Executions per second
Object add new item	378073504.0 Ops/sec
Object spread	38753096.0 Ops/sec

Related benchmarks:

Test method Object (version: 0)

Comparing performance of: Object add new item vs Object spread

Created: 6 years ago by: Guest

Jump to the latest result

Object add new item

Object spread

Suite status: <idle, ready to run>

Experimental features:

Fastest: N/A

Slowest: N/A

Autogenerated LLM Summary (model llama3.2:3b, generated 26 days ago):