Benchmark: toISOString and concatISO

Script Preparation code:

var date = new Date();

function toISOString(date) {
	return date.toISOString();
}

function concat(date) {
 	var d = date.getUTCDate();
	var m = date.getUTCMonth() + 1;
	var y = date.getUTCFullYear();
  	var hh = date.getUTCHours();
 	var mm = date.getUTCMinutes();
  	var ss = date.getUTCSeconds();
  	var ms = date.getUTCMilliseconds();
  	var day = d <= 9 ? '0' + d : '' + d;
    var month = m <= 9 ? '0' + m : '' + m;
    var year = '' + y;
  
  	hh = hh <= 9 ? '0' + hh : '' + hh;
    mm = mm <= 9 ? '0' + mm : '' + mm;
    ss = ss <= 9 ? '0' + ss : '' + ss;
    ms = ms <= 9 ? '0' + ms : '' + ms;
    ms = ms <= 99 ? '0' + ms : '' + ms;
  
	return year + '-' + month + '-' + day + 'T' + hh + ':' + mm + ':' + ss + '.' + ms + 'Z';
}

Tests:

toISOString
for (var i=0; i<1000; ++i) { toISOString(date); }
concat
for (var i=0; i<1000; ++i) { concat(date); }

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
toISOString
concat

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 two JavaScript microbenchmarks, `toISOString` and `concat`, which test the performance of converting a Date object to an ISO string using the `toISOString()` and `concat()` functions, respectively.

**`toISOString()` function:**
This function is not a standard JavaScript method. Instead, it's a part of the ECMAScript Standard library, which provides a `toISOString()` method for `Date` objects. This method returns a string representation of the date in ISO format, including the year, month, day, hour, minute, second, and millisecond.

The `toISOString()` function is compared to a custom implementation provided in the benchmark definition. The custom implementation concatenates various properties of the `date` object using string formatting rules to produce an equivalent ISO string.

**Comparison options:**

There are two comparison options:

1. **Built-in `toISOString()` method**: This option uses the standard JavaScript `toISOString()` method for converting Date objects to ISO strings.
2. **Custom implementation**: This option uses a custom function that concatenates various properties of the `date` object using string formatting rules to produce an equivalent ISO string.

**Pros and Cons:**

1. **Built-in `toISOString()` method**:
	* Pros: Faster execution, as it's a built-in method optimized for performance.
	* Cons: May not be as efficient if implemented in a specific way (e.g., concatenating properties instead of using the standard formatting).
2. **Custom implementation**:
	* Pros: Can be more flexible and customizable, allowing developers to optimize the formatting process.
	* Cons: May be slower due to the overhead of string manipulation.

**Other considerations:**

1. **Library usage**: Neither benchmark uses any external libraries besides the standard JavaScript library for `Date` objects.
2. **Special JS feature or syntax**: The custom implementation uses string formatting rules, which is a valid JavaScript syntax, but it's not explicitly mentioned in the JSON as a special feature.

**Alternatives:**

Other alternatives to measure the performance of converting Date objects to ISO strings could include:

1. Using a different format for the output string (e.g., `YYYY-MM-DDTHH:mm:ss.sssZ` instead of `YYYY-MM-DDTHH:mm:ss.sssZ`).
2. Adding more iterations or variations in the benchmark definition.
3. Comparing with other browsers, devices, or operating systems to account for differences in execution speed.

It's worth noting that MeasureThat.net provides a wide range of benchmarks and test cases to cover various aspects of JavaScript performance, so this specific benchmark might not be unique or the only option available on the platform.

Latest run results:

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

User agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/90.0.4430.212 Safari/537.36

Browser/OS: Chrome 90 on Mac OS X 10.15.7

View result in a separate tab

Test name	Executions per second
toISOString	1725.3 Ops/sec
concat	3097.5 Ops/sec

Related benchmarks:

toISOString and concatISO (version: 0)

Comparing performance of: toISOString vs concat

Created: 3 years ago by: Guest

Jump to the latest result

toISOString

concat

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):