Benchmark: Extension stripping

Tests:

RegExp string replace
const stripExtension = (path) => path.replace(/\.\w+$/, ''); stripExtension('short') stripExtension('with.ext') stripExtension('longer/path/with-segments/and/an-extension.png')
lastIndexOf and string.slice
const stripExtension = (path) => { const periodIndex = path.lastIndexOf('.'); return periodIndex < path.length - 1 ? path.slice(0, periodIndex) : path; } stripExtension('short') stripExtension('with.ext') stripExtension('longer/path/with-segments/and/an-extension.png')
lastIndexOf and string.substring
const stripExtension = (path) => { const periodIndex = path.lastIndexOf('.'); return periodIndex < path.length - 1 ? path.substring(0, periodIndex) : path; } stripExtension('short') stripExtension('with.ext') stripExtension('longer/path/with-segments/and/an-extension.png')
lastIndexOf and regexp test on rest
const extRE = /^\.\w+$/; const stripExtension = (path) => { const periodIndex = path.lastIndexOf('.'); const rest = path.slice(periodIndex); return rest && extRE.test(rest) ? path.slice(0, periodIndex) : path; } stripExtension('short') stripExtension('with.ext') stripExtension('longer/path/with-segments/and/an-extension.png')

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
RegExp string replace
lastIndexOf and string.slice
lastIndexOf and string.substring
lastIndexOf and regexp test on rest

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 benchmarking scenario and explain what's being tested.

**Benchmark Definition**

The benchmark measures different approaches to stripping a file extension from a path string. The script preparation code is empty, which means that the test cases are generated by the user using a specific syntax.

**Test Cases**

There are four test cases:

1. **RegExp String Replace**: This approach uses a regular expression to replace the file extension with an empty string.
2. **lastIndexOf and String Slice**: This approach uses the `lastIndexOf` method to find the last occurrence of '.' in the path and then uses `slice` to extract the substring before the '.'.
3. **lastIndexOf and String Substring**: Similar to the previous approach, but it uses `substring` instead of `slice`.
4. **lastIndexOf and RegExp Test on Rest**: This approach uses `lastIndexOf` to find the last occurrence of '.' in the path, extracts the substring after '.', and then checks if this substring matches a regular expression.

**Libraries and Special Features**

None of these test cases use any external libraries beyond standard JavaScript features. However, some may rely on specific browser behaviors or capabilities (e.g., `lastIndexOf` and `slice` methods are part of the ECMAScript standard).

**Options Compared**

The four test cases compare different approaches to stripping file extensions from a path string:

* Using regular expressions (`RegExp String Replace`)
* Using built-in methods (`lastIndexOf and String Slice`, `lastIndexOf and String Substring`)
* Combining `lastIndexOf` with a regular expression check on the extracted substring (`lastIndexOf and RegExp Test on Rest`)

**Pros and Cons**

Here's a brief summary of each approach:

1. **RegExp String Replace**: This approach is straightforward and efficient, but it may be slower due to the overhead of creating and executing regular expressions.
2. **lastIndexOf and String Slice/Substring**: These approaches are faster because they use built-in methods that are optimized for performance. However, they may not work correctly if the path contains multiple '.' characters or other edge cases.
3. **lastIndexOf and RegExp Test on Rest**: This approach combines the efficiency of `lastIndexOf` with the precision of regular expressions. It's a good balance between speed and accuracy.

**Other Considerations**

* The benchmark only tests these four approaches, so it may not cover all possible scenarios or edge cases.
* The test cases use specific input strings (e.g., 'short', 'with.ext', 'longer/path/with-segments/and/an-extension.png') to demonstrate the behavior of each approach. In a real-world scenario, you might encounter more diverse inputs.
* The benchmark uses Chrome 127 as the browser, which may not be representative of all browsers or environments.

**Alternatives**

If you were to extend this benchmark, you could consider adding other approaches, such as:

* Using `String.prototype.replace` with a regular expression
* Using a custom implementation that iterates over the path string character by character
* Testing the performance of each approach on different types of input (e.g., paths with multiple '.' characters, paths with special characters)

Keep in mind that adding more test cases can increase the complexity and scope of the benchmark, so it's essential to prioritize the most relevant approaches and edge cases.

Latest run results:

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

User agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/127.0.0.0 Safari/537.36

Browser/OS: Chrome 127 on Mac OS X 10.15.7

View result in a separate tab

Test name	Executions per second
RegExp string replace	3498247.2 Ops/sec
lastIndexOf and string.slice	7434968.0 Ops/sec
lastIndexOf and string.substring	7607015.0 Ops/sec
lastIndexOf and regexp test on rest	3313676.0 Ops/sec

Related benchmarks:

Extension stripping (version: 6)

Benchmarks different approaches to stripping a file extension from a path string

Comparing performance of: RegExp string replace vs lastIndexOf and string.slice vs lastIndexOf and string.substring vs lastIndexOf and regexp test on rest

Created: 3 months ago by: Registered User

Jump to the latest result

RegExp string replace

lastIndexOf and string.slice

lastIndexOf and string.substring

lastIndexOf and regexp test on rest

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):