Benchmark: Object.prototype.hasOwnProperty vs obj.hasOwnProperty vs exists check

Script Preparation code:

window.obj = { a: 2 }

Tests:

Object.prototype.hasOwnProperty
Object.prototype.hasOwnProperty.call(obj, 'a');
obj.hasOwnProperty
obj.hasOwnProperty('a');
null check
obj.hasOwnProperty ? obj.hasOwnProperty('a') : true;
function check
typeof obj.hasOwnProperty === 'function' ? obj.hasOwnProperty('a') : true;

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
Object.prototype.hasOwnProperty
obj.hasOwnProperty
null check
function check

Fastest: N/A

Slowest: N/A

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

LLMs can make mistakes. Check important info.

The provided JSON represents a benchmark test case on MeasureThat.net, which compares the performance of three different approaches to check if a property exists in an object.

**Approaches being compared:**

1. **`Object.prototype.hasOwnProperty.call(obj, 'a')`**: This approach uses the `hasOwnProperty` method on the `Object.prototype` to check if the object has a property named `'a'`. The `call` method is used to pass the object and the property name as arguments.
2. **`obj.hasOwnProperty('a')`**: This approach directly calls the `hasOwnProperty` method on the `obj` object, passing the property name as an argument.
3. **`obj.hasOwnProperty ? obj.hasOwnProperty('a') : true`**: This approach uses a conditional expression to check if the `hasOwnProperty` property exists in the object. If it does, the expression evaluates to the result of calling `hasOwnProperty` on the object with the property name.
4. **`typeof obj.hasOwnProperty === 'function' ? obj.hasOwnProperty('a') : true`**: This approach checks the type of the `hasOwnProperty` property using `typeof`. If it's a function (which it should be, since it's a method), the expression evaluates to the result of calling `hasOwnProperty` on the object with the property name.

**Pros and Cons:**

1. **`Object.prototype.hasOwnProperty.call(obj, 'a')`**:
	* Pros: This approach is more explicit and readable, as it clearly separates the property existence check from the actual property lookup.
	* Cons: It's slightly slower due to the method call overhead.
2. **`obj.hasOwnProperty('a')`**:
	* Pros: This approach is faster since it directly calls the `hasOwnProperty` method on the object.
	* Cons: It may be less readable and more prone to errors if not used carefully, as it relies on the fact that `hasOwnProperty` exists in the object's prototype chain.
3. **`obj.hasOwnProperty ? obj.hasOwnProperty('a') : true`**:
	* Pros: This approach is concise and easy to read, but it may be slower due to the conditional expression evaluation overhead.
	* Cons: It's less explicit about the property existence check, making it slightly harder to understand for some readers.
4. **`typeof obj.hasOwnProperty === 'function' ? obj.hasOwnProperty('a') : true`**:
	* Pros: This approach is fast since it uses a simple type check instead of a method call or conditional expression.
	* Cons: It may be less readable and more error-prone, as the type check can fail if `hasOwnProperty` is not defined in the object's prototype chain.

**Library used:**

None, this benchmark does not use any external libraries.

**Special JavaScript features or syntax:**

The test cases do not involve any special JavaScript features or syntax beyond the basic property existence checks.

Latest run results:

Run details: (Test run date: 2 years ago)

User agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/98.0.4758.102 Safari/537.36

Browser/OS: Chrome 98 on Windows

View result in a separate tab

Test name	Executions per second
Object.prototype.hasOwnProperty	3080517.0 Ops/sec
obj.hasOwnProperty	6703662.5 Ops/sec
null check	3303243.5 Ops/sec
function check	3488964.5 Ops/sec

Related benchmarks:

Object.prototype.hasOwnProperty vs obj.hasOwnProperty vs exists check (version: 0)

Comparing performance of: Object.prototype.hasOwnProperty vs obj.hasOwnProperty vs null check vs function check

Created: 3 years ago by: Guest

Jump to the latest result

Object.prototype.hasOwnProperty

obj.hasOwnProperty

null check

function check

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):