@web/test-runner-mocha
Advanced tools
Test framework implementation of Mocha for Web Test Runner
See @web/test-runner for a default implementation and CLI for the test runner.
Mocha relies on global variables, in any JS test file describe and it are available globally and can be used directly:
describe('my test', () => {
it('foo is bar', () => {
if ('foo' !== 'bar') {
throw new Error('foo does not equal bar');
}
});
});
HTML files are loaded in the browser as is, and are not processed by a test framework. This way you have full control over the test environment. Depending on which test framework you're using, the way you run your tests can be a little different.
With mocha, you need to define your tests inside the runTests function:
<html>
<body>
<script type="module">
import { runTests } from '@web/test-runner-mocha';
runTests(async () => {
// write your tests inline
describe('HTML tests', () => {
it('works', () => {
expect('foo').to.equal('foo');
});
});
// or import your test file
await import('./my-test.js');
});
</script>
</body>
</html>
From the HTML page you can load polyfills or libraries to be set up before your tests are run. This is great for testing your code in different environments.
<html>
<body>
<script src="./some-polyfill.js"></script>
<script type="module">
import { mocha, sessionFinished } from '@web/test-runner-mocha';
// see examples above
</script>
</body>
</html>
You can use elements in the <head> to configure different browser environment, such as base path or CSP rules.
<html>
<head>
<meta
http-equiv="Content-Security-Policy"
content="default-src 'self'; img-src https://*; child-src 'none';"
/>
</head>
<body>
<script type="module">
import { mocha, sessionFinished } from '@web/test-runner-mocha';
// see examples above
</script>
</body>
</html>
You can configure mocha options using the testFramework.config option:
module.exports = {
testFramework: {
config: {
ui: 'bdd',
timeout: '2000',
},
},
};
The config entry accepts any of the official mocha browser options.
@open-wc/testing is a general purpose library, including assertions via chai, HTML test fixtures, a11y tests and test helpers.
It is an opinionated implementation which brings together multiple libraries. You could also use the individual libraries together:
For stubbing and mocking, we recommend sinon which ships an es module variant out of the box:
import { stub, useFakeTimers } from 'sinon';
FAQs
Mocha test framework for Web Test Runner
The npm package @web/test-runner-mocha receives a total of 67,040 weekly downloads. As such, @web/test-runner-mocha popularity was classified as popular.
We found that @web/test-runner-mocha demonstrated a not healthy version release cadence and project activity because the last version was released a year ago. It has 7 open source maintainers collaborating on the project.
Did you know?
Socket for GitHub automatically highlights issues in each pull request and monitors the health of all your open source dependencies. Discover the contents of your packages and block harmful activity before you install or update your dependencies.
Security News
Socket and Seal Security collaborate to fix a critical npm overrides bug, resolving a three-year security issue in the JavaScript ecosystem's most popular package manager.
Security News
TypeScript is porting its compiler to Go, delivering 10x faster builds, lower memory usage, and improved editor performance for a smoother developer experience.
Research
Security News
The Socket Research Team has discovered six new malicious npm packages linked to North Korea’s Lazarus Group, designed to steal credentials and deploy backdoors.