Benchmark: Fastest way to check if an Object is empty

Script Preparation code:

var emptyObject = {};
var usedObject = {hi: 'hello', bye: 'goodbye', ping: 'pong'};

function isEmptyLoop(object) {
	for(var prop in object) return false;
	return true;
};

Tests:

Object.keys
console.log(!Object.keys(emptyObject).length); console.log(!Object.keys(usedObject).length);
Loop
console.log(isEmptyLoop(emptyObject)); console.log(isEmptyLoop(usedObject));
JSON.stringify
console.log(JSON.stringify(emptyObject) == '{}'); console.log(JSON.stringify(usedObject) == '{}');

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
Object.keys
Loop
JSON.stringify

Fastest: N/A

Slowest: N/A

Latest 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 break down what is being tested in the provided JSON and explain the different approaches, their pros and cons, and other considerations.

**Benchmark Definition:**

The benchmark is designed to measure the fastest way to check if an object is empty. There are three test cases:

1. **"Object.keys"**: This approach uses the `Object.keys()` method to get an array of the object's property names. If the array has a length of 0, it means the object is empty.
2. **"Loop"**: This approach uses a simple loop to iterate over the object's properties and checks if any of them are defined (i.e., not undefined).
3. **"JSON.stringify"**: This approach converts the object to a JSON string using `JSON.stringify()` and then compares it with an empty string (`'{'`). If they match, it means the object is empty.

**Approaches compared:**

*   **Efficiency:** "Object.keys" is likely to be faster than the loop because it uses an optimized array lookup instead of manual iteration.
*   **Readability:** The loop might be more readable for developers who are not familiar with `Object.keys()`, as it clearly demonstrates the concept of iterating over properties.

**Pros and Cons:**

*   **"Object.keys"**: Pros: Faster, more efficient. Cons: Might not work in older browsers that don't support `Object.keys()`.
*   **"Loop"**: Pros: More readable for developers unfamiliar with `Object.keys()`. Cons: Slower due to manual iteration.
*   **"JSON.stringify"**: Pros: Works across all JavaScript engines and browsers. Cons: Slower due to string conversion and comparison.

**Library/Legacy Feature:**

There is no explicitly mentioned library in the provided benchmark definition, but the use of `Object.keys()` implies that it's a standard feature introduced in ECMAScript 5 (ES5) or later versions. If you were targeting older browsers, you would need to use an alternative approach.

**Special JS Features/Syntax:**

There are no special features or syntaxes used in this benchmark definition.

**Alternatives:**

Other alternatives for checking if an object is empty could include:

*   Using the `== 0` operator directly on the object's length property (e.g., `Object.keys(myObject).length == 0`).
*   Utilizing a library like Lodash, which provides a `isEmpty()` function.
*   Implementing a custom iteration using a more advanced data structure or algorithm.

**Benchmark Preparation Code:**

The script preparation code is provided as follows:
```javascript
var emptyObject = {};
var usedObject = { hi: 'hello', bye: 'goodbye', ping: 'pong' };

function isEmptyLoop(object) {
    for (var prop in object)
        return false;
    return true;
}
```
This defines two objects (`emptyObject` and `usedObject`) with some properties, as well as a custom function called `isEmptyLoop()` that checks if an object is empty by iterating over its properties.

**Individual Test Cases:**

Each test case provides the benchmark definition code in the format "console.log([expression])\nconsole.log([another expression]);". The three test cases are:

1.  **"Object.keys"**: `console.log(!Object.keys(emptyObject).length); console.log(!Object.keys(usedObject).length);`
2.  **"Loop"**: `console.log(isEmptyLoop(emptyObject)); console.log(isEmptyLoop(usedObject));`
3.  **"JSON.stringify"**: `console.log(JSON.stringify(emptyObject) == '{}'); console.log(JSON.stringify(usedObject) == '{}');`

These test cases run the specified expressions and log their results to the console.

Related benchmarks:

Fastest way to check if an Object is empty (version: 0)

Comparing performance of: Object.keys vs Loop vs JSON.stringify

Created: 4 years ago by: Registered User

Jump to the latest result

Object.keys

Loop

JSON.stringify

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):