const str = "https://firebasestorage.googleapis.com/v0/b/a-sketch-a-day-207420.appspot.com/o/"
const str = "https://firebasestorage.googleapis.com/v0/b/a-sketch-a-day-207420.appspot.com/o/"
str.startsWith("h")
const str = "https://firebasestorage.googleapis.com/v0/b/a-sketch-a-day-207420.appspot.com/o/"
str.startsWith("https://firebasestorage.googleapis.com/v0/b/a-sketch-a-day-207420.appspot.com/o")
--enable-precise-memory-info
flag.
Test case name | Result |
---|---|
short | |
long |
Test name | Executions per second |
---|---|
short | 821418752.0 Ops/sec |
long | 3239501.0 Ops/sec |
Let's break down the provided JSON data and explain what's being tested in this JavaScript microbenchmark.
Benchmark Definition
The benchmark definition provides information about the test case, including:
str
to contain a URL. The string has two newline characters (\r\n
) at the end.Individual Test Cases
The individual test cases are defined in an array:
const str = "https://firebasestorage.googleapis.com/v0/b/a-sketch-a-day-207420.appspot.com/o/"str.startsWith("h")
This test case checks if the str
variable starts with the substring "h"
. The code is intentionally short, which is why it's named "short".
const str = "https://firebasestorage.googleapis.com/v0/b/a-sketch-a-day-207420.appspot.com/o/"str.startsWith("https://firebasestorage.googleapis.com/v0/b/a-sketch-a-day-207420.appspot.com/o/")
This test case checks if the str
variable starts with a longer substring, which is also part of the original URL.
Other Considerations
In both test cases, the startsWith()
method is used to check if the string str
matches the specified prefix. The method takes two arguments: the prefix and an optional third argument (not used in this case).
The use of startsWith()
suggests that the benchmark is measuring the performance of this method on various input strings.
Library/Extension Considerations
In neither test case is a specific library or extension mentioned, so it's likely that these are built-in JavaScript functions.
However, if we look at the original string definition:
const str = "https://firebasestorage.googleapis.com/v0/b/a-sketch-a-day-207420.appspot.com/o/"
We can see that this string contains a special character: \r\n
, which is a newline sequence. This might be relevant if the benchmark aims to test the handling of newline sequences in the startsWith()
method.
Special JS Features/Syntax
There are no special JavaScript features or syntax mentioned in these test cases, so we can proceed without further discussion on that front.
Alternatives
For measuring performance and comparing different approaches, some alternatives to MeasureThat.net include:
These tools offer similar functionality to MeasureThat.net and can be used to test various aspects of JavaScript performance.