Benchmark: JavaScript hkjJA performance1

Tests:

Using the spread operator
const firstObject = { sampleData: 'Hello world' } const secondObject = { moreData: 'foo bar' } const finalObject = { ...firstObject, ...secondObject };
Using Object.assign
const firstObject = { sampleData: 'Hello world' } const secondObject = { moreData: 'foo bar' } const finalObject = Object.assign({}, firstObject, secondObject);

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
Using the spread operator
Using Object.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 dive into explaining what's being tested in this benchmark.

The provided JSON represents two individual test cases for measuring JavaScript performance. The first test case, "Using the spread operator," tests how fast JavaScript can merge two objects using the spread operator (`...`). In contrast, the second test case, "Using Object.assign", tests how fast JavaScript can achieve similar results by using the `Object.assign` method.

**Options being compared:**

The benchmark is comparing the performance of two approaches:

1. **Spread Operator (`...`)**: This syntax allows you to merge two objects into a new object, preserving the keys from both sources.
2. **`Object.assign()`**: This method creates a new object by copying properties from an existing source object.

**Pros and Cons of each approach:**

*   **Spread Operator (`...`):**
    *   Pros:
        *   More concise and readable code
        *   Allows for more expressive syntax (e.g., preserving the order of keys)
    *   Cons:
        *   May incur a performance penalty due to function call overhead (every time you use it)
*   **`Object.assign()`**: 
    *   Pros: 
        *   Typically faster and more efficient than using the spread operator, as it avoids function call overhead
    *   Cons:
        *   Less readable code, especially for complex merge scenarios

**Library/Additional considerations:**

There are no external libraries used in these benchmark test cases. However, if you're interested in knowing how JavaScript objects are implemented under the hood:

In modern browsers (e.g., Chrome), `Object.assign()` is optimized to use a specialized method called `WebAssembly's `v8::ObjectAssign` which provides better performance compared to JavaScript functions.

**Special JS feature or syntax:**

This benchmark doesn't explicitly test any special JavaScript features or syntax. However, it does rely on the spread operator (`...`) and `Object.assign()`, both of which are widely supported in modern browsers and Node.js environments.

**Alternatives:**

If you want to measure performance for other merge approaches, consider exploring other options:

1.  **`concat()`**: Merge two arrays by concatenating them.
2.  **Array.prototype.reduce()**: Use the reduce method on an array of objects to create a new object with the merged properties.
3.  **Object.merge() (polyfill)**: Implement or use polyfills for `Object.merge()` which allows creating a new object by merging two source objects.

Here's a code snippet illustrating how you can measure performance using these alternative approaches:

```javascript
// Using concat()
const obj1 = { a: 1 };
const obj2 = { b: 2 };

function mergeWithConcat(obj1, obj2) {
    return Object.assign({}, obj1).concat(obj2);
}

console.time('Merge with concat');
mergeWithConcat(obj1, obj2);
console.timeEnd('Merge with concat');

// Using Array.prototype.reduce()
const obj3 = [obj1, obj2];

function mergeWithReduce() {
    return obj3.reduce((acc, val) => ({ ...acc, ...val }), {});
}

console.time('Merge with reduce');
mergeWithReduce();
console.timeEnd('Merge with reduce');

// Note: Object.merge is not supported in most browsers or Node.js environments. 
// Use polyfills for this method if you need to support these cases.
```

The example above shows how you can benchmark performance using these alternative approaches.

Remember, performance comparisons are only as good as the data used to run them and other factors such as system load at the time of execution.

Related benchmarks:

JavaScript hkjJA performance1 (version: 0)

Comparing performance of: Using the spread operator vs Using Object.assign

Created: 2 years ago by: Guest

Jump to the latest result

Using the spread operator

Using Object.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):