Benchmark: Getting last part of path

Script Preparation code:

var list = [];
for (var i = 0; i < 1000; i++) {
  list.push("/foofoo/barbar/asdasdasdasd/foofoobarbar");
}

Tests:

regex
list.forEach(item => { const parts = /^\/([^/]+)(\/.*?)[/]*([^/]*)$/u.exec(item); })
pop
list.forEach(item => { item.split("/").pop() })
slice
list.forEach(item => { item.slice(item.lastIndexOf("/") + 1); })

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
regex
pop
slice

Fastest: N/A

Slowest: N/A

Latest run results:

Run details: (Test run date: 3 years ago)

User agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/90.0.4430.212 Safari/537.36

Browser/OS: Chrome 90 on Mac OS X 10.15.7

View result in a separate tab

Test name	Executions per second
regex	2157.5 Ops/sec
pop	9186.7 Ops/sec
slice	25752.9 Ops/sec

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

LLMs can make mistakes. Check important info.

**Benchmark Explanation**

The provided benchmark tests three different approaches to extract the last part of a path from a string in JavaScript.

The test case is based on a script preparation code that generates an array of 1000 strings, each containing a path with multiple parts separated by slashes. The goal is to measure the performance of extracting the last part of each path using different methods.

**Approaches Compared**

1. **Regular Expressions (regex)**
	* Method: `^\\/([^/]+)(\\/.*?)[/]*([^/]*)$/u.exec(item)`
	* Purpose: Use a regular expression to match the last part of the path, capturing it in group 2.
	* Pros:
		+ Can handle paths with arbitrary complexity and escaping.
		+ Flexible and powerful, but can be slow due to parsing the regex pattern.
	* Cons:
		+ May have performance issues if the regex pattern is complex or large.
		+ Can be error-prone if not properly validated.
2. **String `split` method**
	* Method: `item.split("/").pop()`
	* Purpose: Split the path string into parts using the `/` character as a separator and return the last part.
	* Pros:
		+ Fast and efficient, with a time complexity of O(n), where n is the number of parts in the path.
		+ Simple and easy to understand.
	* Cons:
		+ May not work correctly if the path contains escaped or special characters.
		+ Can be slow if the path has many parts.
3. **String `slice` method**
	* Method: `item.slice(item.lastIndexOf("/") + 1)`
	* Purpose: Find the last occurrence of `/` in the path string and return a new substring starting from that index + 1.
	* Pros:
		+ Fast and efficient, with a time complexity of O(n), where n is the number of parts in the path.
		+ Simple and easy to understand.
	* Cons:
		+ May not work correctly if the path contains escaped or special characters.
		+ Can be slow if the path has many parts.

**Library**

There are no external libraries used in this benchmark. However, it's worth noting that some JavaScript implementations may have internal optimizations or built-in functions for regular expressions, string splitting, and slicing.

**Special JS Feature/Syntax**

This benchmark does not use any special JavaScript features or syntax beyond the standard ECMAScript 2015 (ES6) features.

**Alternatives**

If you need to perform path manipulation in your code, consider using a library like `path` (for Node.js) or `path-browserify` (for browser-based applications), which provide more robust and convenient methods for working with file paths. However, keep in mind that these libraries may introduce additional dependencies and overhead.

For general-purpose string manipulation, the built-in JavaScript `split`, `slice`, and `indexOf` methods are suitable options. If you need to work with regular expressions frequently, consider using a library like `regex-escape` or `regex-parser` for improved performance and error handling.

Related benchmarks:

Getting last part of path (version: 0)

Comparing performance of: regex vs pop vs slice

Created: 3 years ago by: Guest

Jump to the latest result

regex

pop

slice

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):