TestRunner

This test runner is used internally by Puppeteer to test Puppeteer itself.

- testrunner is a library: tests are node.js scripts
- parallel wrt IO operations
- supports async/await
- modular
- well-isolated state per execution thread

$3

``sh
npm install --save-dev @pptr/testrunner
`

$3

Save the following as test.js and run using node:

`sh
node test.js
`

`js
const {TestRunner, Reporter, Matchers} = require('@pptr/testrunner');

// Runner holds and runs all the tests
const runner = new TestRunner({
parallel: 2, // run 2 parallel threads
timeout: 1000, // setup timeout of 1 second per test
});
// Simple expect-like matchers
const {expect} = new Matchers();

// Extract jasmine-like DSL into the global namespace
const {describe, xdescribe, fdescribe} = runner;
const {it, fit, xit} = runner;
const {beforeAll, beforeEach, afterAll, afterEach} = runner;

// Test hooks can be async.
beforeAll(async state => {
state.parallelIndex; // either 0 or 1 in this example, depending on the executing thread
state.foo = 'bar'; // set state for every test
});

describe('math', () => {
it('to be sane', async (state, test) => {
state.parallelIndex; // Very first test will always be ran by the 0's thread
state.foo; // this will be 'bar'
expect(2 + 2).toBe(4);
});
});

// Reporter subscribes to TestRunner events and displays information in terminal
const reporter = new Reporter(runner);

// Run all tests.
runner.run();
``