boneskull

Here's an example of how to debug Mocha v4 if it hangs.

Ensure you're using a Node.js 8 or newer (or any version with async_hooks support).

If you run your test, you'll notice it hangs:

$ mocha test.js

IceCreamYou

/**
 * Utility method to round numbers to a given number of decimal places.
 *
 * Usage:
 *   3.5.round(0) // 4
 *   Math.random().round(4) // 0.8179
 *   var a = 5532; a.round(-2) // 5500
 *   Number.prototype.round(12345.6, -1) // 12350
 *   32..round(-1) // 30 (two dots required since the first one is a decimal)
 */