Package Exports

@web/test-runner-mocha

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Readme

Test Runner Mocha

Test framework implementation of Mocha for Web Test Runner

See @web/test-runner for a default implementation and CLI for the test runner.

Writing tests

Mocha relies on global variables, in any test file describe and it are available globally:

describe('my test', () => {
  it('foo is bar', () => {
    if ('foo' !== 'bar') {
      throw new Error('foo does not equal bar');
    }
  });
});

Configuring mocha to use TDD is not yet supported.

Writing assertions

You can use any assertion library as long as it works in the browser. For example this es module version of chai:

import { expect } from '@bundled-es-modules/chai';

test('foo is bar', () => {
  expect(foo).to.equal('bar');
});

Creating HTML test fixture

To scaffold an HTML test fixture you can use the @open-wc/testing-helpers library.

import { fixture, html } from '@open-wc/testing-helpers';
import { expect } from '@bundled-es-modules/chai';
import '../my-element.js';

describe('my-element', () => {
  it('should render properly', async () => {
    const element = await fixture(html` <my-element></my-element> `);
    expect(element.localName).to.equal('my-element');
  });
});