Karma with Mocha Testing Framework

Qualified has support for testing in-browser code using Karma with Mocha.

There is very little changes necessary from testing normal code, except your code will be run inside a PhantomJS headless browser, enabling you to test browser-specific events.

Language Version

All code run in the browser is transpiled via Babel, so you can safely use ES2015 code.

Using Mocha

Mocha in Karma works the same as the normal Mocha Testing Framework (BDD), with one exception: Chai will already be loaded for you, with expect, should, and assert all available, no require() necessary.

Note on Chai Failure Reporting

By default Chai truncates objects and arrays over 40 characters in length. If you want to show longer objects (especially arrays) to candidates, you should add the following to your preloaded section:

// How many characters to show before truncating long objects? 0 means no truncating.
chai.config.truncateThreshold = 1000;

Including External Libraries (Beta)

There is a lightweight library inclusion feature, based on comments in the Preloaded section. Including comments like the following enables automatic inclusion of well-known libraries.

// @include-external [email protected]

Currently, as a beta feature, we only support the following:

We expect to be expanding this solution to enable dynamic loading of front-end libraries in the near future.

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