kizu is a fast, minimalist test runner for TypeScript and JavaScript, with a small, easy-to-learn API that lets you focus on your tests — not your tooling.
Designed to help you write simple, readable, and maintainable tests.
- Multi-process parallel test runner. Each test file is run in its own process/runtime for performance and isolation benefits. Use on a multicore machine for best results.
- Optimized for speed and simplicity.
- Minimal dependencies.
- Very simple functional assertion API. No need to learn a DSL or framework.
- Built-in powerful diff visualization tool
- Clean, organized output.
- Failed tests are easy to find, grouped at the end of the output.
- Errors or unhandled promise rejections are buffered and grouped under the test file in the output. This helps you know where they came from.
- Clean stack traces with no extra noise.
- Uncaught errors and unhandled promise rejections will cause the test to fail.
- Any spec files without tests, or tests without assertions, result in a failed test.
- Strict and deep equality comparison by default.
- No special configuration needed, and no plugins to install.
- Works great with c8 for code coverage.
- Handles compilation errors gracefully.
import {test} from 'kizu';
// Basic test
function greet(name: string): string {
return `hello, ${name}`;
}
test('greet()', (assert) => {
assert.equal(hello('world'), 'hello, world');
});
// Error handling
function throwError(): never {
throw new Error('oops');
}
test('throwError()', (assert) => {
assert.throws(() => throwError(), /oops/);
});
// Async test
async function fetchData(): Promise<string> {
return Promise.resolve('data');
}
test('fetchData()', async (assert) => {
const data = await fetchData();
assert.equal(data, 'data');
});- Getting Started
- Examples
- API
- Visual Diff Tool
- Best Practices
- Inspiration, Philosophy & Attribution
- FAQ
- Support, Feedback, and Contributions
- Sponsorship
- License
To install and get started with kizu, see our Getting Started guide.
See the examples and src folders for more examples.
- Star this repo if you like it!
- Submit an issue with your problem, feature request or bug report
- Issue a PR against
mainand request review. Make sure all tests pass and coverage is good. - Write about this project in your blog, tweet about it, or share it with your friends!
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