Benchmark: Javascript: Case insensitive string comparison performance 2

Script Preparation code:

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

Tests:

toLowerCase()
a.toLowerCase() === b.toLowerCase()
localeCompare()
a.localeCompare(b,undefined,o)
toLowerCase() FAIL
c.toLowerCase() === b.toLowerCase()
localeCompare() FAIL
c.localeCompare(b,undefined,o)
toLocaleLowerCase()
a.toLocaleLowerCase() === b.toLocaleLowerCase()
toLocaleLowerCase() FAIL
c.toLocaleLowerCase() === b.toLocaleLowerCase()

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
toLowerCase()
localeCompare()
toLowerCase() FAIL
localeCompare() FAIL
toLocaleLowerCase()
toLocaleLowerCase() FAIL

Fastest: N/A

Slowest: N/A

Latest run results:

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

User agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/134.0.0.0 Safari/537.36

Browser/OS: Chrome 134 on Windows

View result in a separate tab

Test name	Executions per second
toLowerCase()	98203224.0 Ops/sec
localeCompare()	159100.1 Ops/sec
toLowerCase() FAIL	102814512.0 Ops/sec
localeCompare() FAIL	164647.0 Ops/sec
toLocaleLowerCase()	24955786.0 Ops/sec
toLocaleLowerCase() FAIL	22704290.0 Ops/sec

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

LLMs can make mistakes. Check important info.

Let's dive into the benchmark.

**What is being tested?**

The provided JSON represents two sets of test cases: individual test cases and a benchmark definition. The primary focus is on string comparison performance in JavaScript.

**Individual Test Cases:**

Each test case evaluates the performance of a specific JavaScript method for case-insensitive string comparisons:

1. `toLowerCase()`: Compares the lowercase versions of two strings.
2. `localeCompare(b, undefined, o)`: Performs a locale-aware comparison between two strings using options (o).
3. `c.toLowerCase() === b.toLowerCase()` and `c.localeCompare(b, undefined, o)`: Similar to the previous two, but with a different string (`c`) used for comparison.
4. `a.toLocaleLowerCase() === b.toLocaleLowerCase()` and `c.LocaleLowerCase() === b.LocaleLowerCase()`: Uses the `toLocaleLowerCase()` method (available in modern browsers) instead of `toLowerCase()`.

These test cases aim to assess the performance differences between these methods, particularly when dealing with case-insensitive comparisons.

**Options:**

The options (`o`) used in `localeCompare(b, undefined, o)` are part of the ECMAScript standard. These options can affect the comparison:

* `sensitivity`: Can be `'base'` (default), `'caseless'`, or `'strict'`. It controls how case is handled during the comparison:
	+ `base`: Performs a base locale-aware comparison.
	+ `caseless`: Ignores case differences when performing the comparison.
	+ `strict`: Performs a strict, case-sensitive comparison.
* `icase`: If present, performs a case-insensitive comparison regardless of the setting for `sensitivity`.
* `numeric`: Forces the result to be a number (e.g., `-1`, `0`, or `1`).
* `ignore`: Specifies which characters should be ignored during the comparison.

**Pros and Cons:**

Here's a brief summary:

* **toLowerCase()**:
	+ Pros: Simple, widely supported, and easy to implement.
	+ Cons: May not perform locale-aware comparisons correctly, as it relies on the browser's default locale settings.
* **localeCompare(b, undefined, o)**:
	+ Pros: Provides locale-aware comparisons with customizable options for sensitivity, icase, numeric, and ignore.
	+ Cons: Requires a basic understanding of locale settings and may have performance implications due to the complexity of these comparisons.
* **toLocaleLowerCase()** (available in modern browsers):
	+ Pros: More accurate and robust than `toLowerCase()` when dealing with locales.
	+ Cons: Not supported by older browsers, which could impact compatibility.

**Other Considerations:**

When selecting a method for case-insensitive string comparisons, consider the following:

* If you need to perform comparisons across different locales or platforms, using locale-aware methods like `localeCompare()` might be necessary.
* In scenarios where performance is critical, using methods like `toLowerCase()` or `toLocaleLowerCase()` (when available) can be more efficient due to their simplicity and lower overhead.
* Be aware of the potential differences in behavior between `toLowerCase()` and `toLocaleLowerCase()`, especially when working with locales that have specific case handling rules.

**Alternatives:**

If you're looking for alternative approaches, consider:

* Using Unicode-aware methods like `String.prototype.normalize('NFD')` or `String.prototype.toLocaleLowerCase()`, which can provide more accurate results in certain cases.
* Implementing your own case-insensitive comparison function using regular expressions or character set manipulation techniques.

Keep in mind that the choice of method depends on your specific requirements, performance constraints, and target audience.

Related benchmarks:

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

Comparing performance of: toLowerCase() vs localeCompare() vs toLowerCase() FAIL vs localeCompare() FAIL vs toLocaleLowerCase() vs toLocaleLowerCase() FAIL

Created: 3 years ago by: Guest

Jump to the latest result

toLowerCase()

localeCompare()

toLowerCase() FAIL

localeCompare() FAIL

toLocaleLowerCase()

toLocaleLowerCase() FAIL

Suite status: <idle, ready to run>

Experimental features:

Fastest: N/A

Slowest: N/A

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