Benchmark: Object.hasOwnProperty vs Object in vs Object[] vs Array.indexOf vs Array.includes vs Reflect.has()

Script Preparation code:

  var object = {},
      array = [],
      i, test = 1000;
  
  for (i = 0; i < 1000; i++) {
   object['something' + i] = true;
   array.push('something' + i);
  }

Tests:

Object.hasOwnProperty
object.hasOwnProperty('something' + test)
Object in
('something' + test) in object
Array.indexOf
array.indexOf('something' + test) !== -1
direct
object['something' + test] === true
Array includes
array.includes('something' + test)
Object.prototype.hasOwnProperty.call(this.storeIndex, index)
Object.prototype.hasOwnProperty.call(object, 'something' + test)
Reflect.has()
Reflect.has(object, 'something' + test)

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
Object.hasOwnProperty
Object in
Array.indexOf
direct
Array includes
Object.prototype.hasOwnProperty.call(this.storeIndex, index)
Reflect.has()

Fastest: N/A

Slowest: N/A

Latest run results:

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

User agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/131.0.0.0 Safari/537.36 Edg/131.0.0.0

Browser/OS: Chrome 131 on Mac OS X 10.15.7

View result in a separate tab

Test name	Executions per second
Object.hasOwnProperty	27436400.0 Ops/sec
Object in	23178378.0 Ops/sec
Array.indexOf	1411909.2 Ops/sec
direct	22657588.0 Ops/sec
Array includes	1393157.2 Ops/sec
Object.prototype.hasOwnProperty.call(this.storeIndex, index)	22163384.0 Ops/sec
Reflect.has()	13901616.0 Ops/sec

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

LLMs can make mistakes. Check important info.

I'll break down the benchmark and its various components.

**Benchmark Overview**

The benchmark measures the performance of different ways to check if an object has a certain property or if an array contains a specific value. The test case uses a fixed JavaScript code to create two objects: `object` and `array`, with 1000 properties/array elements.

**Options Compared**

1. **Object.hasOwnProperty**: This method checks if the object has a property with the given name.
2. **Object in**: This syntax checks if the object has a property with the given value as its key.
3. **Array.indexOf**: This method searches for the specified element in the array and returns its index. If the element is not found, it returns -1.
4. **Array.includes**: This method checks if the array contains an element that matches the specified value.
5. **Reflect.has**: This method checks if an object has a property with the given name.

**Pros and Cons**

*   **Object.hasOwnProperty**:
    *   Pros: Fast, reliable, and widely supported.
    *   Cons: May not work as expected in some cases (e.g., when using `hasOwnProperty()` with prototype chains).
*   **Object in**:
    *   Pros: Easy to read and write, works well for simple cases.
    *   Cons: Slow due to the overhead of creating a new object and trying to find its key. Not supported in older browsers.
*   **Array.indexOf**:
    *   Pros: Fast, widely supported, but can return -1 if not found, which might be unexpected behavior.
    *   Cons: May not work as expected with large arrays or sparse arrays (arrays with some but not all elements set).
*   **Array.includes**:
    *   Pros: Fast, modern syntax, and widely supported. Returns false if the element is not found instead of returning an index.
    *   Cons: Requires modern JavaScript versions (ES6+), might be slower than `indexOf()` for very large arrays.

**Libraries Used**

1.  **`Object.prototype.hasOwnProperty.call()`**: This method is used in the test case to check if `object` has a property with the given name. It's called through a prototype chain, which makes it slightly slower than direct calls to `hasOwnProperty()`.
2.  None.

**Special JavaScript Features/Syntax**

1.  **ES6+ syntax (`in`, `includes`, `Reflect.has`)**: These features are used in modern browsers (Chromium-based) and require specific version support.
2.  **`Array.prototype.indexOf()`**: This method is a standard part of the Array prototype.

**Other Alternatives**

If you need alternative approaches to performance testing, consider:

1.  Using a different data structure, such as a Set or a Map, which can provide faster lookups and searches.
2.  Using more advanced techniques like caching or memoization to reduce repeated computations.
3.  Investigating browser-specific optimizations (e.g., Chrome's `NativeMessage` API) that might improve performance for your use case.
4.  Considering alternative benchmarking frameworks like Benchmark.js or benchmark-chrome, which offer more features and flexibility.

Related benchmarks:

Object.hasOwnProperty vs Object in vs Object[] vs Array.indexOf vs Array.includes vs Reflect.has() (version: 0)

Comparing performance of: Object.hasOwnProperty vs Object in vs Array.indexOf vs direct vs Array includes vs Object.prototype.hasOwnProperty.call(this.storeIndex, index) vs Reflect.has()

Created: 4 years ago by: Guest

Jump to the latest result

Object.hasOwnProperty

Object in

Array.indexOf

direct

Array includes

Object.prototype.hasOwnProperty.call(this.storeIndex, index)

Reflect.has()

Suite status: <idle, ready to run>

Experimental features:

Fastest: N/A

Slowest: N/A

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