https://github.com/callstackincubator/react-native-harness
Harness brings Jest-style tests to real native environments so you can test TurboModules like you would test your React Native app: with JavaScript.
https://github.com/callstackincubator/react-native-harness
react-native testing-tools
Last synced: about 2 months ago
JSON representation
Harness brings Jest-style tests to real native environments so you can test TurboModules like you would test your React Native app: with JavaScript.
- Host: GitHub
- URL: https://github.com/callstackincubator/react-native-harness
- Owner: callstackincubator
- License: mit
- Created: 2025-06-17T07:41:33.000Z (12 months ago)
- Default Branch: main
- Last Pushed: 2026-04-07T08:20:58.000Z (about 2 months ago)
- Last Synced: 2026-04-07T08:28:08.335Z (about 2 months ago)
- Topics: react-native, testing-tools
- Language: TypeScript
- Homepage: https://react-native-harness.dev
- Size: 4.86 MB
- Stars: 265
- Watchers: 2
- Forks: 11
- Open Issues: 5
-
Metadata Files:
- Readme: README.md
- Changelog: CHANGELOG.md
- Contributing: CONTRIBUTING.md
- License: LICENSE
- Code of conduct: CODE_OF_CONDUCT.md
Awesome Lists containing this project
README
### Jest-style tool for testing native behavior directly on devices
[![mit licence][license-badge]][license]
[![npm downloads][npm-downloads-badge]][npm-downloads]
[![Chat][chat-badge]][chat]
[![PRs Welcome][prs-welcome-badge]][prs-welcome]
Bridge the testing gap: Jest-style tests in real native environments. Get the convenience of describe/it with full access to native modules.
## Features
- **Jest-Style Syntax, Native Power**: Write familiar describe/it tests that run in real iOS and Android environments with full native module access.
- **Best of Both Worlds**: Unlike Jest (Node.js only) or Maestro (UI-based), get convenient test syntax AND native environment execution.
- **Real Device, Simulator & Web Testing**: Execute tests on iOS simulators, Android emulators, or in a browser (Web) — catch platform-specific issues Jest can't see.
- **Native Module Testing**: Test native modules, platform APIs, and device-specific functionality that's impossible with JavaScript-only runners.
- **Familiar Test Structure**: Use beforeEach, afterEach, describe, it, expect — all the testing patterns you know and love from Jest.
- **Zero Configuration Setup**: Drop-in replacement for your existing test workflow with TypeScript support and seamless CI/CD integration.
## Quick Configuration Example
```javascript
// rn-harness.config.mjs
import {
androidPlatform,
androidEmulator,
physicalAndroidDevice,
} from '@react-native-harness/platform-android';
import {
applePlatform,
applePhysicalDevice,
appleSimulator,
} from '@react-native-harness/platform-apple';
const config = {
entryPoint: './src/main.tsx',
appRegistryComponentName: 'MyApp',
runners: [
androidPlatform({
name: 'android',
device: androidEmulator('Pixel_8_API_35'),
bundleId: 'com.myapp',
}),
applePlatform({
name: 'ios',
device: appleSimulator('iPhone 16 Pro Max', '18.0'),
bundleId: 'com.myapp',
}),
],
defaultRunner: 'android',
};
export default config;
```
## Documentation
The documentation is available at [react-native-harness.dev](https://react-native-harness.dev). You can also use the following links to jump to specific topics:
- [Quick Start](https://react-native-harness.dev/docs/getting-started/quick-start)
- [Configuration](https://react-native-harness.dev/docs/getting-started/configuration) (Metro port, plugins, timeouts, coverage, and more)
- [Problem Statement](https://react-native-harness.dev/docs/getting-started/problem-statement)
- [Feature Comparison](https://react-native-harness.dev/docs/feature-comparison)
- [Running in CI/CD](https://react-native-harness.dev/docs/guides/ci-cd)
- [API Reference](https://react-native-harness.dev/docs/api/defining-tests)
## Made with ❤️ at Callstack
`react-native-harness` is an open source project and will always remain free to use. If you think it's cool, please star it 🌟. [Callstack][callstack-readme-with-love] is a group of React and React Native geeks, contact us at [hello@callstack.com](mailto:hello@callstack.com) if you need any help with these or just want to say hi!
Like the project? ⚛️ [Join the team](https://callstack.com/careers/?utm_campaign=Senior_RN&utm_source=github&utm_medium=readme) who does amazing stuff for clients and drives React Native Open Source! 🔥
[callstack-readme-with-love]: https://callstack.com/?utm_source=github.com&utm_medium=referral&utm_campaign=react-native-harness&utm_term=readme-with-love
[license-badge]: https://img.shields.io/npm/l/react-native-harness?style=for-the-badge
[license]: https://github.com/callstackincubator/react-native-harness/blob/main/LICENSE
[npm-downloads-badge]: https://img.shields.io/npm/dm/react-native-harness?style=for-the-badge
[npm-downloads]: https://www.npmjs.com/package/react-native-harness
[prs-welcome-badge]: https://img.shields.io/badge/PRs-welcome-brightgreen.svg?style=for-the-badge
[prs-welcome]: ./CONTRIBUTING.md
[chat-badge]: https://img.shields.io/discord/426714625279524876.svg?style=for-the-badge
[chat]: https://discord.gg/xgGt7KAjxv