Benchmark: Object.create(null) vs Object literal - Creation and Iteration Performance (including Object.keys vs hasOwnPropertyCheck)

Tests:

Object.create
const object = Object.create(null); object.a = 1; object.b = 2; object.c = 3; object.d = 4; object.e = 5; object.f = 6; object.g = 7; object.h = 8; let sum = 0, key; for (key in object) { sum += object[key]; }
Object literal (hasOwnProperty check iteration)
const object = {a: 1, b: 2, c: 3, d: 4, e: 5, f: 6, f: 7, h: 8}; let sum = 0, key; for (key in object) { if (object.hasOwnProperty(key)) { sum += object[key]; } }
Object literal (keys() iteration)
const object = {a: 1, b: 2, c: 3, d: 4, e: 5, f: 6, f: 7, h: 8}; const keys = Object.keys(object); let sum = 0; for (let i = 0, key; i < keys.length; i++) { sum += object[keys[i]]; }

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
Object.create
Object literal (hasOwnProperty check iteration)
Object literal (keys() iteration)

Fastest: N/A

Slowest: N/A

Autogenerated LLM Summary (model gemma2:9b, generated one month ago):

LLMs can make mistakes. Check important info.

This benchmark compares different approaches to creating and iterating over JavaScript objects:

**Options Compared:**

1. **`Object.create(null)`:**  This method creates an object with no prototype chain, using `null` as the prototype. 
2. **Object Literal (with `hasOwnProperty` check):** This creates an object directly using curly braces and iterates over its keys using a `for...in` loop, but includes a `hasOwnProperty(key)` check to avoid enumerating inherited properties.
3. **Object Literal (with `keys()` method):**  This also uses an object literal and iterates over its keys, but instead of relying on `for...in`, it utilizes the `Object.keys()` method to get an array of all owned property names and then loops through that array.

**Pros and Cons:**

* **`Object.create(null)`:**
    * **Pros:** Can be slightly faster for simple object creation, especially if you need a completely isolated object without any inherited properties. 
    * **Cons:** Might require more explicit management of prototype chains if you later need to extend the object's behavior.

* **Object Literal (with `hasOwnProperty` check):**
    * **Pros:**  Direct and readable syntax, the `hasOwnProperty` check ensures that only own properties are iterated over.
    * **Cons:** Can be slightly slower than `Object.create(null)` for pure object creation, and the `hasOwnProperty` check adds a slight performance overhead.

* **Object Literal (with `keys()` method):**
    * **Pros:**  Generally considered more performant than using `for...in` with `hasOwnProperty`. The `keys()` method returns an array of property names directly. 
    * **Cons:** Introduces an extra step of calling the `Object.keys()` method, which might be slightly less intuitive for beginners.

**Other Considerations:**

* **Context Matters:**  The actual performance difference between these approaches can vary depending on the specific browser engine and the size and complexity of your objects. 
* **Readability vs. Performance:** Often, readability and maintainability are more important than slight performance gains.

Let me know if you have any other questions or want to explore other aspects of this benchmark!

Latest run results:

Run details: (Test run date: 3 months ago)

User agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:129.0) Gecko/20100101 Firefox/129.0

Browser/OS: Firefox 129 on Windows

View result in a separate tab

Test name	Executions per second
Object.create	12176886.0 Ops/sec
Object literal (hasOwnProperty check iteration)	12477613.0 Ops/sec
Object literal (keys() iteration)	10485983.0 Ops/sec

Related benchmarks:

Object.create(null) vs Object literal - Creation and Iteration Performance (including Object.keys vs hasOwnPropertyCheck) (version: 0)

Comparing performance of: Object.create vs Object literal (hasOwnProperty check iteration) vs Object literal (keys() iteration)

Created: 2 years ago by: Guest

Jump to the latest result

Object.create

Object literal (hasOwnProperty check iteration)

Object literal (keys() iteration)

Suite status: <idle, ready to run>

Experimental features:

Fastest: N/A

Slowest: N/A

Autogenerated LLM Summary (model gemma2:9b, generated one month ago):