Benchmark: indexOf vs split for finding sub string

Script Preparation code:

var test1 = 'what a test tester testing'
var test2 = 'test tester'
var test3 = 'mytest'

Tests:

indexOf
var result1 = (test1.indexOf('test') == 1); var result2 = (test2.indexOf('test') == 1); var result3 = (test3.indexOf('test') == 1);
split
var result1 = (test1.split('test')[0].length == 1); var result2 = (test2.split('test')[0].length == 1); var result3 = (test3.split('test')[0].length == 1);

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
indexOf
split

Fastest: N/A

Slowest: N/A

Autogenerated LLM Summary (model gemma2:9b, generated 26 days ago):

LLMs can make mistakes. Check important info.

This benchmark compares the performance of two methods for finding a substring within a larger string: `indexOf` and `split`.

**How they work:**

* **`indexOf`**: This method directly searches for a specific substring within a given string. It returns the index (position) of the first occurrence of the substring, or -1 if it's not found.
    *  In this benchmark, `indexOf('test')` is used to check if 'test' appears at index 1 within each test string.
* **`split`**: This method divides a string into an array of substrings based on a specified separator.  
    * Here, `split('test')` splits each string at the occurrence of 'test'. Then `.length` is used to check the length of the substring before the split, effectively determining if 'test' was present at index 1.

**Pros and Cons:**

* **indexOf**:
    * **Pros:** Generally faster for a simple substring search, as it's designed specifically for that purpose.
    * **Cons:** Doesn't provide additional information like splitting the string into parts.
* **split**:
    * **Pros:** More versatile; can split strings based on any separator and provides an array of substrings.
    * **Cons:** Can be slower than `indexOf` for a simple search because it performs more operations.

**Other Considerations:**

* **Context matters:**  The best method depends on the specific task. If you just need to know if a substring exists at a particular position, `indexOf` is usually faster. If you need to split the string into parts, `split` is necessary.
* **String length and complexity:** For very long strings or complex patterns, performance differences might become more significant.

**Alternatives:**

There are other libraries or techniques for string manipulation in JavaScript:

* **Regular expressions (`RegExp`)**: Powerful for pattern matching and searching within strings.

Let me know if you'd like to dive deeper into any specific aspect!

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/116.0.0.0 Safari/537.36 OPR/102.0.0.0

Browser/OS: Opera 102 on Windows

View result in a separate tab

Test name	Executions per second
indexOf	9621658.0 Ops/sec
split	6014002.5 Ops/sec

Related benchmarks:

indexOf vs split for finding sub string (version: 0)

testing speed

Comparing performance of: indexOf vs split

Created: one year ago by: Guest

Jump to the latest result

indexOf

split

Suite status: <idle, ready to run>

Experimental features:

Fastest: N/A

Slowest: N/A

Autogenerated LLM Summary (model gemma2:9b, generated 26 days ago):