Benchmark: startswith vs includes for same string

Tests:

includes
const str = "https://firebase.com/this/is/a/long/thing" str.includes("https://firebase")
startsWith
const str = "https://firebase.com/this/is/a/long/thing" str.startsWith("https://firebase")

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
includes
startsWith

Fastest: N/A

Slowest: N/A

Latest run results:

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

User agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/124.0.0.0 Safari/537.36

Browser/OS: Chrome 124 on Mac OS X 10.15.7

View result in a separate tab

Test name	Executions per second
includes	78755640.0 Ops/sec
startsWith	44279032.0 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 definition and test cases to understand what is being tested.

**Benchmark Definition Overview**

The provided benchmark definition is for a simple JavaScript microbenchmark that compares the performance of two string methods: `includes` and `startsWith`. The benchmark aims to measure which method is faster for searching a specific substring within a longer string.

**Script Preparation Code**

There is no Script Preparation Code provided, which means that the script will be executed from scratch on each test run. This helps ensure consistency in the results.

**Html Preparation Code**

There is also no Html Preparation Code provided, indicating that the benchmark does not require any specific HTML setup or rendering.

**Individual Test Cases**

The benchmark consists of two test cases:

1. `includes`: Searches for the substring `"https://firebase"` within the string `"https://firebase.com/this/is/a/long/thing"`.
2. `startsWith`: Starts with the substring `"https://firebase"` at the beginning of the string `"https://firebase.com/this/is/a/long/thing"`.

**Library and Features**

There are no explicit libraries mentioned in the benchmark definition or test cases. However, it's likely that these tests are using built-in JavaScript methods `includes` and `startsWith`, which are part of the ECMAScript standard.

**Options Compared**

The options being compared are:

1. `includes`: Searches for the substring anywhere within the string.
2. `startsWith`: Starts with the substring at the beginning of the string.

**Pros and Cons of Each Approach**

* `includes`:
	+ Pros: More flexible, can find the substring anywhere in the string, and might be more suitable for certain use cases.
	+ Cons: Can be slower for larger strings due to the need to search every character.
* `startsWith`:
	+ Pros: Faster than `includes`, as it only needs to check the first few characters of the string.
	+ Cons: Less flexible, as it requires the substring to be at the beginning of the string.

**Other Considerations**

The benchmark likely aims to measure the performance difference between these two methods in a specific use case. The results will indicate which method is faster for searching a substring within a longer string.

**Alternative Approaches**

If you need to search for a substring within a larger string, you might consider using other approaches:

1. Regular expressions: Can provide more flexibility and power for matching patterns.
2. Substring iteration: Loops through the characters of the string to find the substring.

Keep in mind that these alternatives might have different performance characteristics depending on the specific use case and input data.

I hope this explanation helps you understand what is being tested in the MeasureThat.net benchmark!

Related benchmarks:

startswith vs includes for same string (version: 0)

Comparing performance of: includes vs startsWith

Created: one year ago by: Guest

Jump to the latest result

includes

startsWith

Suite status: <idle, ready to run>

Fastest: N/A

Slowest: N/A

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