Benchmark: new Date(date) vs new Date(normalizeToLocalDate(date)) 2

Script Preparation code:

var dateTimeISO = '2024-08-21T17:00:00.000Z'
var dateOnlyISO = '2024-08-21'

var normalizeToLocalDate = (date) => ` ${date}`

Tests:

new Date(dateTimeISO)
new Date(dateTimeISO)
new Date(normalizeToLocalDate(dateTimeISO))
new Date(normalizeToLocalDate(dateTimeISO))
new Date(dateOnlyISO)
new Date(dateOnlyISO)
new Date(normalizeToLocalDate(dateOnlyISO))
new Date(normalizeToLocalDate(dateOnlyISO))

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
new Date(dateTimeISO)
new Date(normalizeToLocalDate(dateTimeISO))
new Date(dateOnlyISO)
new Date(normalizeToLocalDate(dateOnlyISO))

Fastest: N/A

Slowest: N/A

Latest run results:

Run details: (Test run date: 4 months ago)

User agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/127.0.0.0 Safari/537.36

Browser/OS: Chrome 127 on Mac OS X 10.15.7

View result in a separate tab

Test name	Executions per second
new Date(dateTimeISO)	4279278.5 Ops/sec
new Date(normalizeToLocalDate(dateTimeISO))	4273234.0 Ops/sec
new Date(dateOnlyISO)	5783702.5 Ops/sec
new Date(normalizeToLocalDate(dateOnlyISO))	2984259.8 Ops/sec

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

LLMs can make mistakes. Check important info.

Let's dive into the world of JavaScript microbenchmarks!

**Benchmark Definition**

The provided JSON defines two benchmark definitions:

1. `new Date(date) vs new Date(normalizeToLocalDate(date)) 2`: This benchmark compares the performance of two approaches to create a Date object from a string:
	* `new Date(date)`
	* `new Date(normalizeToLocalDate(date))`

**Script Preparation Code**

The script preparation code is provided in the "Script Preparation Code" field of the benchmark definition:

```javascript
var dateTimeISO = '2024-08-21T17:00:00.000Z'
var dateOnlyISO = '2024-08-21'

var normalizeToLocalDate = (date) => ` ${date}`
```

This code defines two variables: `dateTimeISO` and `dateOnlyISO`. The `normalizeToLocalDate` function is also defined, which takes a date string as input and returns a modified version of it.

**Html Preparation Code**

The html preparation code is not provided in the benchmark definition. However, you can assume that it would be used to set up any necessary HTML environment for running the benchmarks.

**Individual Test Cases**

The individual test cases are defined in the "Test Name" field of each object:

```javascript
[
    {
        "Benchmark Definition": "new Date(dateTimeISO)",
        "Test Name": "new Date(dateTimeISO)"
    },
    {
        "Benchmark Definition": "new Date(normalizeToLocalDate(dateTimeISO))",
        "Test Name": "new Date(normalizeToLocalDate(dateTimeISO))"
    },
    {
        "Benchmark Definition": "new Date(dateOnlyISO)",
        "Test Name": "new Date(dateOnlyISO)"
    },
    {
        "Benchmark Definition": "new Date(normalizeToLocalDate(dateOnlyISO))",
        "Test Name": "new Date(normalizeToLocalDate(dateOnlyISO))"
    }
]
```

These test cases create four different Date objects using the `new Date()` constructor, with varying inputs.

**Library**

There is no explicit library mentioned in the benchmark definition. However, the `normalizeToLocalDate` function uses template literals (introduced in ECMAScript 2015) to concatenate strings with the input date string. Template literals are a feature of JavaScript that allow you to embed expressions inside string literals.

**Special JS Feature or Syntax**

There is no special JavaScript feature or syntax mentioned in the benchmark definition. The only feature used is template literals (introduced in ECMAScript 2015), which is a built-in feature of modern JavaScript.

**Other Alternatives**

To run these benchmarks, you would need to create a web page that includes the HTML and script preparation code provided in the benchmark definition. You can then use a JavaScript execution engine or a benchmarking library (such as Benchmark.js) to execute the test cases and measure their performance.

Here's an example of how you could set up a basic environment for running these benchmarks:

```html
<!DOCTYPE html>
<html>
<head>
    <title>Benchmark</title>
</head>
<body>
    <script src="benchmark.js"></script>
    <script>
        var dateTimeISO = '2024-08-21T17:00:00.000Z'
        var dateOnlyISO = '2024-08-21'

var normalizeToLocalDate = (date) => ` ${date}`

function runBenchmark(benchmarkDefinition) {
            var testCode = eval(benchmarkDefinition.BenchmarkDefinition)
            // Execute the test code and measure its performance
            console.log(testCode())
        }

for (var i = 0; i < benchmarkTestCases.length; i++) {
            runBenchmark(benchmarkTestCases[i])
        }
    </script>
</body>
</html>
```

Note that this is just a basic example, and you would need to modify it to suit your specific needs.

In conclusion, the provided benchmark definition uses modern JavaScript features such as template literals to create Date objects. The benchmarks compare the performance of two approaches: using `new Date()` directly versus using `new Date(normalizeToLocalDate(date))`.

Related benchmarks:

new Date(date) vs new Date(normalizeToLocalDate(date)) 2 (version: 0)

Comparing performance of: new Date(dateTimeISO) vs new Date(normalizeToLocalDate(dateTimeISO)) vs new Date(dateOnlyISO) vs new Date(normalizeToLocalDate(dateOnlyISO))

Created: 4 months ago by: Registered User

Jump to the latest result

new Date(dateTimeISO)

new Date(normalizeToLocalDate(dateTimeISO))

new Date(dateOnlyISO)

new Date(normalizeToLocalDate(dateOnlyISO))

Suite status: <idle, ready to run>

Experimental features:

Fastest: N/A

Slowest: N/A

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