Getting Started in Unit Tests

mockyeah makes it easy to mock requests in your unit tests.

To ease setup & use for popular unit test frameworks, mockyeah maintains some packages - see packages for jest and mocha. Or you can configure manually for your test framework of choice.

Here's an example of using mockyeah in unit tests with jest:

const mockyeah = require('@mockyeah/test-jest');
const supertest = require('supertest');

const request = supertest(mockyeah.server.url);

describe('Wondrous service', () => {
  it('should create a mock service that returns an internal error', done => {
    // create failing service mock
    mockyeah.get('/wondrous', { status: 500 });

    // assert service mock is working
    request.get('/wondrous').expect(500, done);
  });

  it('should create a mock service that returns JSON', done => {
    // create service mock that returns json data
    mockyeah.get('/wondrous', { json: { foo: 'bar' } });

    // assert service mock is working
    request.get('/wondrous').expect(200, { foo: 'bar' }, done);
  });

  it('should verify a mock service expectation', () =>
    // create service mock with expectation
    mockyeah
      .get('/wondrous', { text: 'it worked' })
      .expect()
      .params({
        foo: 'bar'
      })
      .once()
      // invoke request and verify expectation
      .run(request.get('/wondrous?foo=bar'))
      .verify());
});

See Mock API and Expectation API for more details.

Configure Manually

You'll want to construct a mockyeah instance with the following options, and wire it into before/after each/all hooks for your testing framework.

const Mockyeah = require('@mockyeah/fetch');

const mockyeah = new Mockyeah({
  noWebSocket: true
  // other options...
});

// Tell mockyeah to reset its mocks after each test
//  with lifecycle hooks in your unit test framework:

afterEach(() => mockyeah.reset());

// ...