sinon-test | Wrap your tests in a sandbox with auto-cleanup | Game Engine library

First of all, when asking a StackOverflow question, it makes sense to post a fully runnable example and stating all dependencies. Basically, I used more than an hour trying to test this out because both were missing.

This is the fully expanded example, just with dummy implementations of your two main objects.

Since no one looked at this to realize it wasn't as simple a unequal assertion I'll post the real answer I finally figured out.

Basically I was approaching the tests wrong. I was only half accounting for non-async code inside of javascript.

What I need to do was return a promise to mocha's it function. In order to do that my controller needed to return a promise as well. In the case of doing database stuff I could just return the database call promise.

Once the promise calls either resolve or reject. You can then do your assertions to see if the tests work.

They key is you have to chain your promises from the bottom of your controller all the way back up to the it function of mocha.

Below is the code to resolve this.

By default the sandboxes that Sinon creates have their configuration set so that the sandbox configuration option useFakeTimers is true. (Search for defaultConfig in this documentation page.)

This means that while the sandbox is in effect, the clock appears to be stopped, and Bluebird's delay never resolves. You tell sinon-test to create sandboxes without fake timers by passing a 2nd parameter when you configure it. This 2nd parameter is actually a configuration object for Sinon sandboxes: