assert.js is a port of the Node.js standard assertion library for the browser. The original code and tests are from Node.js, and have been modified to be browser compatible.
For example, you can use it with Mocha to perform tests on the both sides (server-side and client-side). Mocha does not supply it's own assertion library.
You can use the standard assert module when running mocha on Node.js.
The same tests will run in the browser if you use this library.
<script src="assert.js"></script> <script src="path/to/testing-framework.js"></script> <script src="path/to/your/test.js"></script>
test/index.html in your browser,
and see the console.
> node test/test-assert.js All OK
MIT (same as Node.js)