OT2004 : Mock Objects: Driving Top-Down Development
Here’s what we covered:
* OO concepts: an application is a web of collaborating objects, each providing a distinct responsibility and taking on multiple roles to provide services to other objects.
* How the process of using mock objects complements TDD to drive out the design of these responsibilities and roles.
* How our original usage of mocks for testing system boundaries such as databases, web-apps, GUIs, external libraries turned out to be a bad approach and the success we started achieving when inverting this to only mock types we can change.
* The process of using mocks very quickly points out key abstractions in your system, difference in responsibilities between objects and services objects require.
* Clearing up misconceptions about mocks, including: not using them at system boundaries and what they actually are (not stubs, not recorders, no behaviour).
* Our first public demonstration of the new JMock API to walk through a single iteration of the process.
* Usage patterns.