And so it begins! London is first up. Sandro Mancuso takes the lead for the next five episodes, creating a twitter-like app using the outside-in "London School" approach.
In this episode Sandro completes the first few use cases. The acceptance tests for those use cases pass. The unit tests and the production code are written.
And, in this episode, we see the first hint of the double edged sword of mocking. We see how the outside in approach drives architecture. We see how the unit tests drive design. And we also see how the prodigious use of mocks may make the unit tests and production code fragile.
Note: You will find all the code in
https://github.com/sandromancuso/cleancoders_openchat here. Three branches are of interest.
starting-point branch is where both implementations began.
openchat-outside-in branch captures the tomato by tomato history of the London approach.
openchat-unclebob branch captures the tomato by tomato history of the Chicago approach.