README.md
TestRunner
This test runner is used internally by Playwright to test Playwright itself.
- testrunner is a library: tests are
node.js
scripts - parallel wrt IO operations
- supports async/await
- modular
- well-isolated state per execution thread
Example
Save the following as test.js
and run using node
:
node test.js
const {TestRunner, Reporter, Matchers} = require('.');
// 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();