Because we have several Notes models, the test suite should run against any model. We can write tests using the Notes model API we developed, and an environment variable should be used to declare the model to test.
Because we've written the Notes application using ES6 modules, we have a small challenge to overcome. Mocha only supports running tests in CommonJS modules, and Node.js (as of this writing) does not support loading an ES6 module from a CommonJS module. An ES6 module can use import to load a CommonJS module, but a CommonJS module cannot use require to load an ES6 module. There are various technical reasons behind this, the bottom line is that we're limited in this way.
Because Mocha requires that tests be ...
