Benchmark: Creation of an Array of Date ISO Strings

Tests:

For loop + Array.push
const start = new Date("2020-06-01"); const end = new Date("2026-05-01"); let dates = []; for (let currentDate = start; currentDate <= end; currentDate.setMonth(currentDate.getMonth() + 1)) { dates.push(currentDate.toISOString().split("T")[0]); }
x

const start = new Date("2020-06-01");
const end = new Date("2026-05-01");
let dates = [];

for (let currentDate = start; currentDate <= end; currentDate.setMonth(currentDate.getMonth() + 1)) {
dates.push(currentDate.toISOString().split("T")[0]);
}
For loop + Spread Operator
const start = new Date("2020-06-01"); const end = new Date("2026-05-01"); let dates = []; for (let currentDate = start; currentDate <= end; currentDate.setMonth(currentDate.getMonth() + 1)) { dates = [...dates, currentDate.toISOString().split('T')[0]]; }
const start = new Date("2020-06-01");
const end = new Date("2026-05-01");
let dates = [];

for (let currentDate = start; currentDate <= end; currentDate.setMonth(currentDate.getMonth() + 1)) {
dates = [...dates, currentDate.toISOString().split('T')[0]];
}

While + Array.push

const start = new Date("2020-06-01");
const end = new Date("2026-05-01");
let dates = [];
let currentDate = start;

while (currentDate <= end) {
      dates.push(currentDate.toISOString().split("T")[0]);
      currentDate.setMonth(currentDate.getMonth() + 1);
    }

 
const start = new Date("2020-06-01");const end = new Date("2026-05-01");let dates = [];let currentDate = start;​while (currentDate <= end) {      dates.push(currentDate.toISOString().split("T")[0]);      currentDate.setMonth(currentDate.getMonth() + 1);    }

While + Spread Operator

const start = new Date("2020-06-01");
const end = new Date("2026-05-01");
let dates = [];
let currentDate = start; 

while (currentDate <= end) {
      dates = [...dates, currentDate.toISOString().split('T')[0]];
      currentDate.setMonth(currentDate.getMonth() + 1);
    }

 
const start = new Date("2020-06-01");const end = new Date("2026-05-01");let dates = [];let currentDate = start; ​while (currentDate <= end) {      dates = [...dates, currentDate.toISOString().split('T')[0]];      currentDate.setMonth(currentDate.getMonth() + 1);    }

Array.from

const start = new Date("2020-06-01");
const end = new Date("2026-05-01");
let dates = Array.from(
      { length: (end.getFullYear() - start.getFullYear()) * 12 },
      (_, i) => new Date(start.getFullYear(), start.getMonth() + i, 1).toISOString().split('T')[0]
    );

 
const start = new Date("2020-06-01");const end = new Date("2026-05-01");let dates = Array.from(      { length: (end.getFullYear() - start.getFullYear()) * 12 },      (_, i) => new Date(start.getFullYear(), start.getMonth() + i, 1).toISOString().split('T')[0]    );

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Experimental features:

Memory measurements supported only in Chrome.
For precise memory measurements Chrome must be launched with --enable-precise-memory-info flag.
More information: Monitoring JavaScript Memory

Test case name	Result
For loop + Array.push
For loop + Spread Operator
While + Array.push
While + Spread Operator
Array.from

Fastest: N/A

Slowest: N/A

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/109.0.0.0 Safari/537.36

Browser/OS: Chrome 109 on Windows

View result in a separate tab

Test name	Executions per second
For loop + Array.push	11180.5 Ops/sec
For loop + Spread Operator	9885.8 Ops/sec
While + Array.push	11469.3 Ops/sec
While + Spread Operator	9992.7 Ops/sec
Array.from	10061.9 Ops/sec

Autogenerated LLM Summary (model llama3.2:3b, generated 6 months ago):

Benchmark Overview

The provided benchmark measures the performance of different approaches to create an array of Date ISO strings within a specified date range.

Options Compared

The benchmark compares five different approaches:

For loop + Array.push: This approach uses a traditional for loop to iterate through each day in the specified date range, and pushes the Date ISO string into an array.
For loop + Spread Operator: This approach uses a for loop to iterate through each day in the specified date range, and uses the spread operator to append the Date ISO string to the array.
While + Array.push: This approach uses a while loop to iterate through each day in the specified date range, and pushes the Date ISO string into an array using the Array.push() method.
While + Spread Operator: This approach uses a while loop to iterate through each day in the specified date range, and uses the spread operator to append the Date ISO string to the array.
Array.from: This approach uses the Array.from() method to create an array of Dates within the specified date range, and then maps each Date to its ISO string.

Pros and Cons

Here's a brief summary of the pros and cons for each approach:

For loop + Array.push:
- Pros: Simple and easy to understand.
- Cons: May be slower due to the overhead of array push operations.
For loop + Spread Operator:
- Pros: Similar performance to Array.push, but with a more concise syntax.
- Cons: May have slightly lower performance due to the spread operator's overhead.
While + Array.push:
- Pros: Can be faster than for loops due to fewer function calls.
- Cons: May have higher memory usage due to the array growth.
While + Spread Operator:
- Pros: Similar performance to While + Array.push, but with a more concise syntax.
- Cons: May have slightly lower performance due to the spread operator's overhead.
Array.from:
- Pros: Fast and efficient, especially for large datasets.
- Cons: Requires understanding of Array.from() and its options.

Library and Special JS Feature

No special JavaScript features or libraries are used in this benchmark. The benchmark focuses on demonstrating different approaches to creating an array of Date ISO strings using built-in JavaScript methods.

Other Considerations

When optimizing performance-critical code, it's essential to consider factors such as:

Memory allocation and deallocation
Function call overhead
Array growth and shrinkage
Cache locality

In this benchmark, the approach that performs best will likely be one that balances these considerations effectively.

LLMs can make mistakes. Check important info.

**Benchmark Overview**

The provided benchmark measures the performance of different approaches to create an array of Date ISO strings within a specified date range.

**Options Compared**

The benchmark compares five different approaches:

1. **For loop + Array.push**: This approach uses a traditional for loop to iterate through each day in the specified date range, and pushes the Date ISO string into an array.
2. **For loop + Spread Operator**: This approach uses a for loop to iterate through each day in the specified date range, and uses the spread operator to append the Date ISO string to the array.
3. **While + Array.push**: This approach uses a while loop to iterate through each day in the specified date range, and pushes the Date ISO string into an array using the Array.push() method.
4. **While + Spread Operator**: This approach uses a while loop to iterate through each day in the specified date range, and uses the spread operator to append the Date ISO string to the array.
5. **Array.from**: This approach uses the `Array.from()` method to create an array of Dates within the specified date range, and then maps each Date to its ISO string.

**Pros and Cons**

Here's a brief summary of the pros and cons for each approach:

* **For loop + Array.push**:
	+ Pros: Simple and easy to understand.
	+ Cons: May be slower due to the overhead of array push operations.
* **For loop + Spread Operator**:
	+ Pros: Similar performance to Array.push, but with a more concise syntax.
	+ Cons: May have slightly lower performance due to the spread operator's overhead.
* **While + Array.push**:
	+ Pros: Can be faster than for loops due to fewer function calls.
	+ Cons: May have higher memory usage due to the array growth.
* **While + Spread Operator**:
	+ Pros: Similar performance to While + Array.push, but with a more concise syntax.
	+ Cons: May have slightly lower performance due to the spread operator's overhead.
* **Array.from**:
	+ Pros: Fast and efficient, especially for large datasets.
	+ Cons: Requires understanding of `Array.from()` and its options.

**Library and Special JS Feature**

**Other Considerations**

When optimizing performance-critical code, it's essential to consider factors such as:

* Memory allocation and deallocation
* Function call overhead
* Array growth and shrinkage
* Cache locality

In this benchmark, the approach that performs best will likely be one that balances these considerations effectively.

Related benchmarks:

Creation of an Array of Date ISO Strings (version: 0)

Compare the performance of different ways to create an Array of Date ISO Strings

Comparing performance of: For loop + Array.push vs For loop + Spread Operator vs While + Array.push vs While + Spread Operator vs Array.from

Created: 2 years ago by: Guest

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For loop + Array.push

For loop + Spread Operator