Package Exports
- jest-performance-matchers
- jest-performance-matchers/main.js
This package does not declare an exports field, so the exports above have been automatically detected and optimized by JSPM instead. If any package subpath is missing, it is recommended to post an issue to the original package (jest-performance-matchers) to support the "exports" field. If that is not possible, create a JSPM override to customize the exports field for this package.
Readme
jest-performance-matchers
A minimalistic library with jest matchers(assertions) for measuring code performance in node.js
Prerequisites
jest-performance-matchers only supports
- Jest version 27.0.0 and newer
- Node.js version 14.0.0 and newer
How to install
With npm:
npm intall --save-dev jest-performance-matchers
Setup
Either import the matcher in test you want to use them :
import 'jest-performance-matchers';
Or create a setup script and add to setupFilesAfterEnv
as instructed
in Configuring Jest :
// setupPerformanceMatchers.js
import 'jest-performance-matchers';
// jest.config.js
"jest": {
"setupFilesAfterEnv": ['<rootDir>/setupPerformanceMatchers.js']
}
How to use the matchers
.toCompleteWithin
Assert that the synchronous code runs within the given duration:
import 'jest-performance-matchers';
describe('Test the performance of synchronous code', () => {
test("Should complete in 10 ms at most", () => {
expect(() => {
// Do something that should complete in 10 ms at most;
}).toCompleteWithin(10);
});
test("Should not complete in less than 10 ms", () => {
expect(() => {
// Do something that should not complete in less than 10 ms;
}).not.toCompleteWithin(10);
});
});
.toCompleteWithinQuantile
Assert that the synchronous code executed for I
times, runs Q
% the time within the given duration:
import 'jest-performance-matchers';
describe('Test the performance of synchronous code', () => {
test("Should be executed 100 times and 95% of the time should complete in 10 ms at most", () => {
expect(() => {
// Do something that 95% of the time should complete in 10 ms at most;
}).toCompleteWithinQuantile(10, {iterations: 100, quantile: 95});
});
test("Should be executed 100 times and 95% of the time should not complete in less 10 ms", () => {
expect(() => {
// Do something that 95% of the time should not complete in less 10 ms;
}).not.toCompleteWithinQuantile(10, {iterations: 100, quantile: 95});
});
});
.toResolveWithin
Assert that the asynchronous code resolves within the given duration:
import 'jest-performance-matchers';
describe('Test the performance of asynchronous code', () => {
test("Should resolve in 10 ms at most (async)", async () => {
await expect(async () => {
// await for a promise that should resolve in 10 ms at most;
}).toResolveWithin(10);
});
test("Should resolve in 10 ms at most (promise)", async () => {
return expect(() => {
// return a promise that should resolve in 10 ms at most;
}).toResolveWithin(10);
});
test("Should not resolve in less than 10 ms (promise)", async () => {
return expect(() => {
// return a promise that should not resolve in less than 10 ms;
}).not.toResolveWithin(10);
});
});
.toResolveWithinQuantile
Assert that the asynchronous code resolves for I
times, runs Q
% the time within the given duration:
import 'jest-performance-matchers';
describe('Test the performance of asynchronous code', () => {
test("Should be executed 100 times and 95% of the time should resolve for 10 ms at most", async () => {
await expect(async () => {
// await for a promise that 95% of the time should resolve for 10 ms at most;
}).toResolveWithinQuantile(10, {iterations: 100, quantile: 95});
});
test("Should be executed 100 times and 95% of the time should not resolve in less than 10 ms", async () => {
await expect(() => {
// return a promise that 95% of the time should not resolve in less than 10 ms;
}).not.toResolveWithinQuantile(10, {iterations: 100, quantile: 95});
});
});
How to Contribute
Contributions from the community are highly appreciated. Here are ways you can contribute to this project:
Reporting Issues: If you find bugs or have suggestions, open an issue.
Code Contributions: Submit code changes through pull requests.
Documentation: Improve project documentation through pull requests.
Support: Simply give the project a star, your support is greatly appreciated!
Getting Started
Fork the repository and clone it to your local environment.
Create a new branch for your changes.
Make your changes, commit them with descriptive messages, and push to your forked repository.
Create a Pull Request (PR) from your branch to the main repository.
If you have any questions, feel free to reach out. Happy coding!