Benchmark: (many keys fixed) hasOwnPropery vs Loop vs if ... in vs Object.entries

Script Preparation code:

const keysLength = 100 * 1000;
var value = {}
for (let i = 0; i < keysLength; i++) {
    if (i === 50 * 1000) {
        value.name = 'Mark'
    }
    value[i] = i
}

Tests:

hasOwnPropery
value.hasOwnProperty('name');
Loop
for (const key in value) { if (key === 'name') break; }
if ... in
if ('name' in value) { }
Object.entries
Object.entries(value).find(x => x[0] === 'name')

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
hasOwnPropery
Loop
if ... in
Object.entries

Fastest: N/A

Slowest: N/A

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

LLMs can make mistakes. Check important info.

Let's dive into the world of JavaScript microbenchmarks on MeasureThat.net.

**Benchmark Definition JSON**

The provided JSON represents a benchmark definition for multiple test cases. Here's what's tested:

* The `hasOwnProperty` vs `Loop` vs `if ... in` vs `Object.entries` comparison is being evaluated for its performance.
* The script preparation code creates an object with 100,000 properties and sets one property to `'name'` at a specific iteration (`50,000` iterations).

**Options Compared**

The four options compared are:

1. **hasOwnProperty**: Uses the `in` operator to check if a property exists in an object.
2. **Loop**: Iterates through the object's properties using a traditional loop.
3. **if ... in**: Combines an `if` statement with the `in` operator to check for property existence.
4. **Object.entries**: Uses the `Object.entries()` method to iterate over an object's key-value pairs.

**Pros and Cons of Each Approach**

Here's a brief summary:

* **hasOwnProperty**: Pros: Simple, efficient; Cons: May be slower than other methods due to caching or branching overhead.
* **Loop**: Pros: Control over iteration order; Cons: Can be slower for large objects due to unnecessary iterations.
* **if ... in**: Pros: Combines conditional checking with property existence; Cons: May have branching overhead, affecting performance.
* **Object.entries**: Pros: Modern and efficient way to iterate over objects; Cons: May not be as familiar to older developers.

**Library and Syntax Used**

In this benchmark, the `in` operator is used extensively. The `hasOwnProperty` option uses this operator directly. The `if ... in` approach also leverages this operator.

No special JavaScript features or syntax are mentioned in the benchmark definition.

**Other Considerations**

When writing benchmarks like these, it's essential to consider factors such as:

* **Object size**: Increasing the object size can reveal performance differences between methods.
* **Browser and engine variations**: Different browsers and engines may have varying optimizations for each method.
* **Caching and memoization**: Some methods, like `hasOwnProperty`, might benefit from caching or memoization.

**Alternatives**

For similar benchmarking purposes, you could consider using:

1. micro-benchmarking libraries like `Benchmark.js` or `js-benchmark`.
2. Online platforms like `jsperf` (now defunct) or `jsbench`.

Keep in mind that the choice of benchmarking library or platform depends on your specific needs and goals.

Hope this explanation helps!

Latest run results:

Run details: (Test run date: 10 months ago)

User agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/120.0.0.0 Safari/537.36

Browser/OS: Chrome 120 on Windows

View result in a separate tab

Test name	Executions per second
hasOwnPropery	32806432.0 Ops/sec
Loop	344.7 Ops/sec
if ... in	34825204.0 Ops/sec
Object.entries	109.2 Ops/sec

Related benchmarks:

(many keys fixed) hasOwnPropery vs Loop vs if ... in vs Object.entries (version: 1)

Comparing performance of: hasOwnPropery vs Loop vs if ... in vs Object.entries

Created: 11 months ago by: Registered User

Jump to the latest result

hasOwnPropery

Loop

if ... in

Object.entries

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):