Enough theory! Let's get our hands dirty with some practical examples using the Alcohology app from Chapter 9, A Shopping Application. First, we'll drill down into the guts of the application and build a unit test for some of the key business functionality. Then, we'll jump up to a high-level view and check whether our building blocks integrate correctly.

There are a wealth of tools we can use for both. The Ext JS framework has begun to build a set of unit tests to verify its behavior and cut out regressions in core functionality. To do so, Sencha has chosen the Jasmine library.

Jasmine is a behavior-driven framework, a term that relates to the way tests are described. Rather than using the "assertation" terminology, it uses the "expectation...