How to write unit tests for server side Meteor code?

I have some server side code -- meteor methods and simple backend helpers -- that I would like to test. I've read the documentation testing with Meteor, but I am having a hard time connecting the documentation to my very simple use case. Can someone share with me how they've tested a meteor method or a simple backend JS function?

For instance, let's say you have some server method in, some_methods.js

function someHelper() {
// does lots of cool stuff
};

Meteor.methods({
  'user/update' (userProperties) {
     // updating some user properties
   }
})