uvu

What is uvu?

The uvu npm package is a highly performant and lightweight test runner/framework for JavaScript, designed to execute tests quickly and support both Node.js and browser environments. It provides a simple API for defining and running tests, as well as assertions to validate code.

What are uvu's main functionalities?

Test Definition and Execution

This feature allows you to define and run tests. The code sample demonstrates how to define a simple test suite with uvu to test the Math.sqrt function.

const { test } = require('uvu');
const assert = require('uvu/assert');

test('Math.sqrt()', () => {
  assert.is(Math.sqrt(4), 2);
  assert.is(Math.sqrt(144), 12);
  assert.is(Math.sqrt(2), Math.SQRT2);
});

test.run();

Asynchronous Test Support

uvu supports asynchronous tests, allowing you to test asynchronous operations like fetching data from an API. The code sample shows an asynchronous test that awaits the resolution of a fetchData function.

const { test } = require('uvu');
const assert = require('uvu/assert');

test('async test', async () => {
  const data = await fetchData();
  assert.is(data, expectedData);
});

test.run();

Hooks

uvu provides hooks like before, after, before.each, and after.each to set up preconditions and clean up after tests. The code sample illustrates how to use before.each and after.each hooks in a test suite.

const { test, suite } = require('uvu');
const assert = require('uvu/assert');

const mathSuite = suite('math');

mathSuite.before.each(() => {
  // setup code before each test
});

mathSuite.after.each(() => {
  // cleanup code after each test
});

mathSuite('Math.pow()', () => {
  assert.is(Math.pow(2, 3), 8);
});

mathSuite.run();

Other packages similar to uvu

mocha

Mocha is a feature-rich JavaScript test framework running on Node.js and in the browser, making asynchronous testing simple. It's more heavyweight compared to uvu and offers a wider range of built-in features like test retries and flexible reporting.

jest

Jest is a delightful JavaScript Testing Framework with a focus on simplicity. It works out of the box for any React project and provides a more integrated testing solution with features like snapshot testing, global setup/teardown, and a built-in coverage reporter. Jest is more opinionated and comprehensive than uvu, which is minimalistic and focused on performance.

ava

AVA is a test runner for Node.js with a concise API, detailed error output, and process isolation that lets you develop with confidence. AVA is similar to uvu in its minimalism and focus on performance, but it also offers unique features like concurrent test execution and built-in support for TypeScript.

tape

Tape is a tap-producing test harness for Node.js and browsers. It's minimal and flexible, with only a small set of core methods. Tape is similar to uvu in its simplicity and ease of use, but it produces TAP output, which can be consumed by any TAP reporter for more detailed results.

README

The README file is missing