Benchmark: Javascript: Case insensitive string comparison performance with indexOf 2

Script Preparation code:

var a = "John Doe"
var b = "john doe"
var c = "john smith"
var o = {
    sensitivity: 'base'
}

Tests:

toLowerCase()
a.toLowerCase().indexOf(b.toLowerCase()) !== -1
localeCompare()
a.localeCompare(b,undefined,o)

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
toLowerCase()
localeCompare()

Fastest: N/A

Slowest: N/A

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

LLMs can make mistakes. Check important info.

Let's break down the provided benchmark and explain what's being tested, compared, and considered.

**Benchmark Overview**

The benchmark measures the performance of two string comparison methods in JavaScript: `toLowerCase()` and `localeCompare()`. The test cases compare strings "John Doe" (with lowercase letters) with "john doe" (case-insensitive).

**Script Preparation Code**

The script preparation code creates three variables:

* `a`: a case-sensitive string "John Doe"
* `b`: a case-insensitive version of the previous string, "john doe"
* `c`: another case-sensitive string "john smith" (not used in this benchmark)
* An object `o` with a single property `sensitivity` set to `'base'`. The purpose of this object is not immediately clear without more context.

**Html Preparation Code**

There is no HTML preparation code provided, which means the benchmark only runs in a JavaScript environment (e.g., web browser).

**Test Cases**

The benchmark consists of two test cases:

1. `toLowerCase()`: Compares `a.toLowerCase()` with `b.toLowerCase()`.
2. `localeCompare()`: Compares `a.localeCompare(b, undefined, o)`.

**Comparison Options**

The two comparison options differ in their approach to handling case sensitivity:

1. **`toLowerCase()`**: This method converts both strings to lowercase before comparing them.
	* Pros: Simple and efficient, as it only requires a single string conversion.
	* Cons: May not handle Unicode characters correctly (depending on the locale) or edge cases like zero-width characters.
2. **`localeCompare()`**: This method compares strings based on the locale's formatting rules, which can include case handling. The `o` object specifies the comparison options:
	* Pros: Can handle a wider range of languages and Unicode characters correctly, as well as edge cases.
	* Cons: May be slower than `toLowerCase()`, as it involves more complex logic.

**Library/External Dependency**

The `localeCompare()` method uses the Intl API (Internationalization API), which is a JavaScript standard. The `Intl` object provides functions for working with internationalized strings, including locale-based string comparisons.

**Special JS Feature/Syntax**

This benchmark does not use any special JavaScript features or syntax that are not widely supported.

**Alternatives**

If you're interested in exploring alternative approaches, consider the following:

* Use a different case-insensitive comparison library, like `string-case-fold-enum`.
* Implement your own custom string comparison function using a regular expression or other approach.
* Experiment with using `regex` for case-insensitive matching (although this may not be as efficient or reliable as `toLowerCase()` or `localeCompare()`).

Keep in mind that the benchmark's primary goal is to compare the performance of these two built-in JavaScript methods. If you're interested in exploring alternative approaches, it's essential to evaluate their performance and compatibility with your specific use case.

Latest run results:

Run details: (Test run date: one year ago)

User agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/114.0.0.0 Safari/537.36

Browser/OS: Chrome 114 on Windows

View result in a separate tab

Test name	Executions per second
toLowerCase()	4433623.5 Ops/sec
localeCompare()	95871.7 Ops/sec

Related benchmarks:

Javascript: Case insensitive string comparison performance with indexOf 2 (version: 0)

Comparing performance of: toLowerCase() vs localeCompare()

Created: one year ago by: Guest

Jump to the latest result

toLowerCase()

localeCompare()

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):