Benchmark: startswith vs includes with samillar pattern

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/128.0.0.0 Safari/537.36

Browser/OS: Chrome 128 on Mac OS X 10.15.7

View result in a separate tab

Test name	Executions per second
includes	217553632.0 Ops/sec
startsWith	55014608.0 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 JSON benchmark data to explain what's being tested and compare different approaches.

**Benchmark Overview**

The `MeasureThat.net` website allows users to create and run JavaScript microbenchmarks. The provided JSON represents two individual test cases, each testing a different string comparison method: `includes` and `startsWith`. The benchmark is focused on measuring the performance of these methods with similar patterns.

**Test Cases**

There are two test cases:

1. **`includes`**: Tests if the string `str` includes the substring `"https://firebase/"`.
2. **`startsWith`**: Tests if the string `str` starts with the substring `"https://firebase/"`.

**Approaches Compared**

Both methods (`includes` and `startsWith`) are compared to determine which is more efficient.

* **`includes`**: Uses a simple string search algorithm, where it iterates through the input string until it finds the specified substring.
* **`startsWith`**: Also uses a string search algorithm, but with a twist. It performs a starting point check on the first character of the string and then checks if subsequent characters match.

**Pros and Cons**

Here are some pros and cons for each approach:

* **`includes`**:
	+ Pros: Simple to implement, easy to understand.
	+ Cons: May be slower than `startsWith` due to its linear search nature.
* **`startsWith`**:
	+ Pros: Can take advantage of early return optimization (EPO), which allows it to exit the function as soon as the match is found. This can lead to better performance in many cases.
	+ Cons: Requires a slight increase in code complexity and may not be suitable for all use cases.

**Library Usage**

Neither test case uses a specific library, but `startsWith` method is often implemented using the `String.prototype.startsWith()` or `String.prototype.match()` methods. However, these libraries are typically not considered when benchmarking pure JavaScript performance.

**Special JS Feature/Syntax**

There are no special JS features or syntax used in this benchmark. The focus is on comparing the performance of two basic string comparison methods.

**Alternatives**

If you need to benchmark other string comparison methods, here are some alternatives:

1. `localeCompare()`: A method that compares strings based on their locale and collation.
2. `indexOf()`/`lastIndexOf()`: Methods that find the index of a substring within another string. These can be compared to `includes` and `startsWith`.
3. `substring()`: A method that extracts a portion of a string. This can be used as an alternative to `includes` and `startsWith`.

Keep in mind that each approach has its own trade-offs, and the best choice depends on your specific use case and requirements.

In summary, this benchmark tests the performance difference between two basic string comparison methods: `includes` and `startsWith`. The `startsWith` method is expected to perform better due to its early return optimization (EPO) mechanism.

Related benchmarks:

startswith vs includes with samillar pattern (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):