Benchmark: Spread vs object.assing vs forEach

Tests:

Spread
const a = { email: "abc@mail.com", phone: "12345678", }; const b = { app_version: "AP.12", appsflyer_id: "askldjajkshdlkjh2323h4234j2l3j4h", advertising_id: "23;o4h2l34hl2kj3h4kj23h4", device_os_version: "12", device_name: "Aifon 15 PRO", firebase_instance_id: "2liu3hiuo23y4u23y4ui2y34iy3u4y234", }; const res = { email: null, phone: null, last_name: null, first_name: null, app_version: null, appsflyer_id: null, advertising_id: null, device_os_version: null, device_name: null, firebase_instance_id: null, ...a, ...b };
Object.assign
const a = { email: "abc@mail.com", phone: "12345678", }; const b = { app_version: "AP.12", appsflyer_id: "askldjajkshdlkjh2323h4234j2l3j4h", advertising_id: "23;o4h2l34hl2kj3h4kj23h4", device_os_version: "12", device_name: "Aifon 15 PRO", firebase_instance_id: "2liu3hiuo23y4u23y4ui2y34iy3u4y234", }; const res = Object.assign({ email: null, phone: null, last_name: null, first_name: null, app_version: null, appsflyer_id: null, advertising_id: null, device_os_version: null, device_name: null, firebase_instance_id: null }, a, b);
Foreach
const a = { email: "abc@mail.com", phone: "12345678", last_name: "Last Name", first_name: "First Name", app_version: null, appsflyer_id: null, advertising_id: null, device_os_version: null, device_name: null, firebase_instance_id: null }; const b = { app_version: "AP.12", appsflyer_id: "askldjajkshdlkjh2323h4234j2l3j4h", advertising_id: "23;o4h2l34hl2kj3h4kj23h4", device_os_version: "12", device_name: "Aifon 15 PRO", firebase_instance_id: "2liu3hiuo23y4u23y4ui2y34iy3u4y234", }; const res = { email: null, phone: null, last_name: null, first_name: null, app_version: null, appsflyer_id: null, advertising_id: null, device_os_version: null, device_name: null, firebase_instance_id: null }; Object.keys(a).forEach(key => { res[key] = a[key]; }); Object.keys(b).forEach(key => { res[key] = b[key]; });

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
Spread
Object.assign
Foreach

Fastest: N/A

Slowest: N/A

Latest run results:

Run details: (Test run date: one year ago)

User agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/114.0.0.0 Safari/537.36

Browser/OS: Chrome 114 on Mac OS X 10.15.7

View result in a separate tab

Test name	Executions per second
Spread	10817627.0 Ops/sec
Object.assign	7951115.5 Ops/sec
Foreach	2660588.0 Ops/sec

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

LLMs can make mistakes. Check important info.

Measuring the performance of different JavaScript methods for object creation and assignment is crucial in understanding the efficiency of code execution.

**Benchmark Overview**

The benchmark compares three methods: `Spread`, `Object.assign`, and `Foreach`. The test case involves creating two objects, `a` and `b`, with varying properties. Each method is used to assign these objects to a new object `res`.

**Method Comparison**

### Spread

*   **Description**: The spread operator (`...`) is used to expand an object's properties into a new object.
*   **Pros**: Fast and concise way to create a new object by copying existing ones. It also works well with arrays and other iterable objects.
*   **Cons**: Limited control over the resulting object, as it only copies enumerable properties.

### Object.assign()

*   **Description**: `Object.assign()` is used to copy properties from one or more source objects to a target object.
*   **Pros**: Allows for more control over the resulting object by specifying which properties to copy. It also works with objects and arrays.
*   **Cons**: Can be slower than spread operator due to its function call overhead, especially when dealing with large objects.

### Foreach

*   **Description**: The `forEach()` method is used on arrays or iterable objects to execute a callback function for each element.
*   **Pros**: Allows for control over the resulting object by specifying which properties to copy. It also works with objects and arrays.
*   **Cons**: Slower than spread operator due to its function call overhead, especially when dealing with large objects.

**Other Considerations**

When choosing between these methods, consider the following factors:

*   Performance: Spread operator is generally faster than `Object.assign()` or `forEach()`.
*   Control: `Object.assign()` and `Foreach()` offer more control over the resulting object compared to the spread operator.
*   Code Readability: The choice of method depends on personal preference, but generally, spread operator is considered more concise.

**Browser Variations**

The provided benchmark results are for Chrome 114 on a Mac OS X system. Different browsers may exhibit different performance variations due to their internal optimizations and caching mechanisms.

Related benchmarks:

Spread vs object.assing vs forEach (version: 0)

Comparing performance of: Spread vs Object.assign vs Foreach

Created: one year ago by: Guest

Jump to the latest result

Spread

Object.assign

Foreach

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):