trolling - node library to rollback environment changes in tests

Sometimes you need to interact with environment in tests:

* when you run integrational tests for database layer, you make your database dirt
* when you run end-to-end API tests, you make you backend dirty

This library allows you to define rollback actions in your test cases to keep them clean and (mostly) repeatable.

Installation

``bash
npm install --save trolling
`

Example (with mocha)

`js
const {rollout} = require('trolling');

class Client
{
async createArticle(title) {} // creates article, returns ID
async deleteArticle(id) {} // deletes article by ID
}

describe('my awesome API', () => {
// NOTE: here you wrap mocha callback with 'rollout' which provides 'rollback' for you.
it('can create article', rollout(async (rollback) => {
const client = Client();
const articleId = await client.createArticle();
rollback(async () => {
await client.deleteArticle(articleId);
});

// ...assert with 'chai' and do other stuff
}));
});

`

Features

This library seamlessly works with any test framework - and tested with mocha.

It has only one powerful rollout function which provides rollback function. You can:

* attach multiple rollback actions - they are always called in FIFO order
* attach sync or async rollback actions - rollout will wait asynchronously
* throw exception from rollback action: in such cases rollout` continues rollbacks execution and throws exception when all rollbacks was called

Do you need something else? Create an issue, please.

Best practices for testing and trolling

1. Use this library to rollback changes in your integration or end-to-end tests
2. Run integration and end-to-end tests with rollbacks on developer machine for smoke testing
3. Run the same test suite with CI system for test environment acceptance testing
4. Do not rely on rollbacks - be ready to drop or abandon your environment when something bad happened