Benchmark: Object.hasOwnProperty vs Object in vs Object[] vs Array.indexOf vs Array.includes vs Object.hasOwn

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.hasOwn
Object.hasOwn(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.hasOwn

Fastest: N/A

Slowest: N/A

Latest run results:

No previous 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 the world of JavaScript microbenchmarks!

**Benchmark Overview**

The provided JSON represents a benchmark test that compares six different approaches to check if a property exists in an object or array:

1. `Object.hasOwnProperty`
2. `Object in`
3. `Array.indexOf` (returns -1 if not found)
4. `direct` (simple equality check with the value being searched for)
5. `Array.includes`

**Benchmark Preparation Code**

The script preparation code creates a large object and an array, both with 1000 properties/elements. This is done to ensure that the benchmark test is running on a representative sample of data.

```javascript
var object = {};
array = [];
i, test = 1000;

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

**Individual Test Cases**

Each test case is defined with a unique `Benchmark Definition` and a corresponding `Test Name`. These tests are executed repeatedly to measure their performance.

1. **Object.hasOwnProperty**: Checks if the property exists in the object using `object.hasOwnProperty`.
2. **Object in**: Uses the `in` operator to check if the property exists in the object.
3. **Array.indexOf**: Searches for the property in the array using `indexOf`. If not found, returns -1.
4. **direct**: Performs a simple equality check with the value being searched for.
5. **Array.includes**: Checks if the property exists in the array using `includes`.
6. **Object.hasOwn**: Uses the `hasOwn` method to check if the property exists in the object.

**Pros and Cons**

Here's a brief overview of each approach:

1. **Object.hasOwnProperty**:
	* Pros: Fast, efficient, and supported by all modern browsers.
	* Cons: Only checks for the existence of the property, not its value.
2. **Object in**:
	* Pros: Easy to read and maintain, but slower than `hasOwnProperty` due to the overhead of the `in` operator.
	* Cons: May return false positives if the property is inherited from a prototype.
3. **Array.indexOf**:
	* Pros: Fast for large arrays, but returns -1 on failure, which may affect performance in some cases.
	* Cons: Only works for arrays and can be slower than `hasOwnProperty` or `in`.
4. **direct**:
	* Pros: Simple and fast, but requires explicit value comparison.
	* Cons: May not work as expected if the property is not a string or has a different data type.
5. **Array.includes**:
	* Pros: Fast, efficient, and supported by all modern browsers.
	* Cons: Returns true for any match, even if it's not exactly what you're looking for.

**Library Usage**

None of the test cases use any external libraries.

**Special JS Features/Syntax**

There are no special JavaScript features or syntax used in these benchmark tests. The code is straightforward and easy to understand.

**Alternatives**

If you were to implement a similar benchmark, you could consider using other approaches, such as:

* Using `WeakMap` instead of an object to store the properties
* Creating a custom function to measure performance
* Adding additional test cases to cover more edge cases

However, keep in mind that these alternatives might not provide significant improvements over the existing tests and may introduce new complexity.

I hope this explanation helps software engineers understand the benchmark test and its underlying mechanics!

Related benchmarks:

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

Comparing performance of: Object.hasOwnProperty vs Object in vs Array.indexOf vs direct vs Array includes vs Object.hasOwn

Created: 3 years ago by: Guest

Jump to the latest result

Object.hasOwnProperty

Object in

Array.indexOf

direct

Array includes

Object.hasOwn

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):