Benchmark: isEmptyObject: keys vs for in

Script Preparation code:

function keys(obj) {
    if (!obj) {
        return [];
    }
    if (Object.keys) {
        return Object.keys(obj);
    }
    var keyList = [];
    for (var key in obj) {
        if (obj.hasOwnProperty(key)) {
            keyList.push(key);
        }
    }
    return keyList;
}

function isEmptyObj(obj) {
    return !keys(obj).length;
}

function isEmptyObj2(obj) {
    if (!obj) {
        return true;
    }
    for (var key in obj) {
        if (obj.hasOwnProperty(key)) {
            return false;
        }
    }
    return true;
}

var testObj = {
    "siteId": "81ac2a67a958e7aebff3df41ee9797a9",
    "installs": {
        "HWCsI8jkLgwa": {
            "appId": "dvNRF2bh1fgh",
            "scope": {},
            "options": {
                "theme": "without"
            }
        }
    },
    "internal": {
        "placementErrors": []
    }
}

Tests:

keys
isEmptyObj(testObj)
for in
isEmptyObj2(testObj)

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
keys
for in

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 break down the benchmark and its various components.

**Benchmark Definition JSON**

The provided JSON defines a benchmark with two test cases: `isEmptyObject: keys vs for in`. This means we'll be comparing the performance of two approaches to check if an object is empty: using the `keys()` function and using the `for...in` loop.

**Script Preparation Code**

The script preparation code provides two functions:

1. `keys(obj)`: This function returns an array of keys from the object `obj`. If `Object.keys()` is available (i.e., in modern browsers), it uses that method; otherwise, it manually iterates through the object's properties using a `for...in` loop.
2. `isEmptyObj(obj)`: This function checks if an object `obj` is empty by calling the `keys()` function and checking its length. If the length is 0, the object is considered empty.
3. `isEmptyObj2(obj)`: This function also checks if an object `obj` is empty using a similar approach to `isEmptyObj()`, but it manually iterates through the object's properties using a `for...in` loop.

**Html Preparation Code**

There is no HTML preparation code provided, which means that the benchmark likely only runs in a JavaScript environment or a headless browser.

**Individual Test Cases**

The two test cases are:

1. **Test Case 1: "keys"**
	* Benchmark Definition: `isEmptyObj(keys(testObj))`
	* This test case uses the `keys()` function to extract keys from an object and then checks if the resulting array is empty using `isEmptyObj()`.
2. **Test Case 2: "for in"**
	* Benchmark Definition: `isEmptyObj2(testObj)`
	* This test case manually iterates through the properties of an object `testObj` using a `for...in` loop and checks if any keys are found using `isEmptyObj2()`.

**Library**

There is no explicit library mentioned in the benchmark, but it appears to use built-in JavaScript methods such as `Object.keys()`, `for...in`, and `hasOwnProperty()`.

**Special JS Feature or Syntax**

No special JavaScript features or syntax are used in this benchmark.

**Pros and Cons of Each Approach**

1. **Using `keys()` function**
	* Pros:
		+ More concise and readable code.
		+ Less prone to errors, as it uses a standardized method for extracting keys.
	* Cons:
		+ May not work in older browsers that don't support `Object.keys()`.
2. **Using `for...in` loop**
	* Pros:
		+ Works in older browsers that don't support `Object.keys()`.
	* Cons:
		+ More verbose and error-prone code.
		+ Less readable, as it requires careful handling of the `hasOwnProperty()` method.

**Other Alternatives**

If you wanted to test alternative approaches to checking if an object is empty, some options could include:

1. Using a regex pattern to check for zero-length properties: `isEmptyObj(obj) { return Object.keys(obj).length === 0; }`
2. Using the `Object.assign()` method with an empty object: `isEmptyObj(obj) { return Object.assign({}, obj).length === 0; }`
3. Using a simple loop to iterate through the object's properties and check for emptiness.

Keep in mind that these alternatives may have different performance characteristics or trade-offs, depending on the specific use case and browser environment.

Related benchmarks:

isEmptyObject: keys vs for in (version: 0)

Comparing performance of: keys vs for in

Created: 4 years ago by: Guest

Jump to the latest result

keys

for in

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):