jest-metadata is a library that allows you to attach user-defined data to any jest-circus entity like describe blocks, function definitions, test runs, invocations, and more. Custom reporters can access your custom data to produce rich and insightful reports leveraging low-level details from jest-circus events and any additional data you want to use in your reports.

🌟 Features

* Attach custom metadata to Jest entities such as describe blocks, function definitions, test runs, and invocations.
* Access your metadata from your reporters to generate insightful reports.
* Graceful degradation for default test environments (node, jsdom) and jest-jasmine2 test runner.
* Custom test environment support via a decorator class.

📚 Guidelines

This library is primarily intended for the authors of custom Jest reporters.
Direct usage of jest-metadata in test files is not recommended.

To use jest-metadata, you should:

* Declare jest as a peer dependency (or direct one) in your package.
* Provide your reporter as a class that inherits from jest-metadata/reporter.
Provide your test environment as a decorator class that can inherit from any WithMetadata() class.
* Think about using a namespace for your metadata, so it doesn't clash with other metadata.

The best live example of how to use jest-metadata at the moment is [jest-allure2-reporter].

🚀 Quick Start

To get your hands dirty, you can try out jest-metadata directly in your project.

Install jest-metadata using npm:

``bash
npm install jest-metadata --save-dev
`

In your Jest config, add the following:

`diff
+ "testEnvironment": "jest-metadata/environment-node",
+ "reporters": [
+ "default",
+ "./your-custom-reporter.js",
+ ],
`

If you need to use jest-metadata in a JSDOM environment or another custom test environment,
please refer to the [Integrating jest-metadata into test environment][jest-environment] guide.

📖 Usage

$3

Attach metadata to test entities using annotations:

`js
import { metadata, $Set } from 'jest-metadata';

// Write your own DSL for attaching metadata to test entities
// Try to namespace your metadata to avoid collisions with other libraries
const $Description = (text) => $Set('mycompany.description', text);

$Description('This is a sample test suite.');
describe('Login flow', () => {

$Description('This is a login test.');
it('should login', () => {
// ...
metadata.push('mycompany.attachements', [
{ name: 'screenshot', type: 'image/png', filePath: '/path/to/screenshot.png' },
]);
// ...
});
});
`

$3

Access metadata in a custom Jest reporter:

`js
import { state } from 'jest-metadata';
import { JestMetadataReporter } from 'jest-metadata/reporter';

class CustomReporter extends JestMetadataReporter {
async onTestCaseResult(test, testCaseResult) {
await super.onTestCaseResult(test, testCaseResult);

const metadata = state.getTestFileMetadata(test.path).lastTestEntry;

const titles = [testCaseResult.title, ...testCaseResult.ancestorTitles.slice().reverse()];
const descriptions = [metadata, ...metadata.ancestors()].map((m) => m.get('mycompany.description', '')).find(x => x);
const attachments = [metadata, ...metadata.ancestors()].flatMap((m) => m.get('mycompany.attachements', []));

const n = titles.length;
for (let i = n - 1; i >= 0; i--) {
console.log(${titles[i]}: ${descriptions[i]});
}
// Output:
// > Login flow: This is a sample test suite.
// > should login: This is a login test.
}
}
`

📄 Documentation

For more detailed documentation and examples, see the [docs folder].

🌐 Contributing

We welcome contributions from the community! To get involved, please follow these steps:

* Check the [GitHub issues] for open tasks or [submit a new issue] if you have a feature request or bug report.
* Fork the repository and create a new branch for your changes.
* Make your changes and submit a pull request.

For more information, see our [Contribution Guidelines].

📃 License

This project is licensed under the [MIT License].

[docs` folder]: ./docs
[GitHub issues]: https://github.com/wix-incubator/jest-metadata/issues
[submit a new issue]: https://github.com/wix-incubator/jest-metadata/issues/new/choose
[Contribution Guidelines]: ./CONTRIBUTING.md
[MIT License]: ./LICENSE
[jest-environment]: ./docs/jest-environment.md
[jest-allure2-reporter]: https://github.com/wix-incubator/jest-allure2-reporter