See What's New in the latest version of trialjs.

• trial.monitor - Easily capture information about how functions are used.
• trial.substitute - Describes how the substitute and unsubstitute methods help you easily stub and unstub functions.
• trial.contains - Allows you to see if an object contains another.
• trial.doesThrow - Checks whether a function throws an exception or not.
• trial.exists - Checking to ensure deeply nested object trees exist.
• trial.debug - Easily see debug information about objects.

Further reading: Discover other JavaScript tools.

All trial code is fully Test Driven.