To test the app itself, we can use Velocity Meteor's official testing framework.
Velocity itself doesn't contain tools for testing, but rather gives testing packages such as Jasmine or Mocha a unified way to test Meteor apps and report their output in the console or the apps interface itself using the velocity:html-reporter package.
Let's quote their own words:
Velocity watches your tests/ directory and sends test files to the correct testing plugin. The testing plugin performs the tests and sends results for each test back to Velocity as they complete. Velocity then combines the results from all of the testing plugins and outputs them via one or more reporting plugins. When the app or tests change, Velocity will rerun your tests and reactively update the results.
This is taken from http://velocity.meteor.com. Additionally, Velocity adds features such as Meteor stubs and automatic stubbing. It can create mirror apps for isolated testing and run setup code (fixtures).
We...