Benchmark: Get last path part - Regex vs split

Script Preparation code:

var str = '../../../../../../../src/ui/components/factory'

Tests:

Regex
var lastPath = str.match(/\/([^\/]*)$/)[1]
Split
var pathsParts = str.split('/'); var lastPart = pathsParts[pathsParts.length - 1]

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
Regex
Split

Fastest: N/A

Slowest: N/A

Latest run results:

Run details: (Test run date: 2 years ago)

User agent: Mozilla/5.0 (Linux; Android 10; K) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/122.0.0.0 Mobile Safari/537.36 EdgA/122.0.0.0

Browser/OS: Chrome Mobile 122 on Android

View result in a separate tab

Test name	Executions per second
Regex	2612001.2 Ops/sec
Split	6002493.0 Ops/sec

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

LLMs can make mistakes. Check important info.

Let's break down the provided benchmark and explain what is being tested.

**Benchmark Definition**

The benchmark measures the performance of two approaches to extract the last path part from a string:

1. Using regular expressions (Regex)
2. Using the `split()` method with a delimiter (`/`)

**Options Compared**

Two options are compared:

a. **Regex**: Uses regular expression to extract the last part of the path.
b. **Split**: Uses the `split()` method to split the path into parts and extracts the last part.

**Pros and Cons of Each Approach**

1. **Regex**:
	* Pros: Can be used for more complex string matching, flexible syntax.
	* Cons: Can be slower due to the complexity of the regex engine, may not work well with all types of input data (e.g., non-ASCII characters).
2. **Split**:
	* Pros: Simple and efficient, works well with most types of input data.
	* Cons: May not work well with paths that contain multiple consecutive slashes (`//`), which can lead to incorrect results.

**Library Used**

None are explicitly mentioned in the benchmark definition. However, it's likely that the `match()` method used for Regex is part of the JavaScript standard library.

**Special JS Feature/Syntax**

The benchmark uses a feature called "non-capturing group" (`(?:)`) which allows us to extract only the last path part without capturing the entire match. This feature is not explicitly mentioned in the benchmark definition, but it's worth noting for those familiar with regex syntax.

**Other Alternatives**

Other alternatives could include:

* Using `substring()` or `slice()` methods to extract a substring from the original string.
* Using a library like `path` (for Node.js) or `path-browserify` (for browser-side usage) to work with path manipulation.
* Using a parsing library like `estraverse` or `jsonparse` for more complex string parsing tasks.

**Benchmark Preparation Code**

The preparation code sets up the input string `str` by concatenating a path using relative paths (`../../../../../../../src/ui/components/factory`). This allows us to easily test both approaches on a consistent string.

**Individual Test Cases**

There are two test cases:

1. **Regex**: Tests the performance of using regular expression to extract the last path part.
2. **Split**: Tests the performance of using the `split()` method with a delimiter (`/`) to extract the last path part.

The benchmark results show that the `Split` approach is faster than the `Regex` approach in this specific test case, indicating that the `split()` method is more efficient for this particular use case.

Related benchmarks:

Get last path part - Regex vs split (version: 1)

Comparing performance of: Regex vs Split

Created: 2 years ago by: Registered User

Jump to the latest result

Regex

Split

Suite status: <idle, ready to run>

Fastest: N/A

Slowest: N/A

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