TDD and the SOLID principles (Part 3 – OCP)

Wednesday, September 7, 2011

Table of contents: Part1 – Indrocution Part 2 – SRP Part 3 – OCP (this post) Part 4 – LSP Part 5 – ISP Part 6 – DIP Part 7 – Conclusion The Open/Close Principle The Open/Close Principle states that: SOFTWARE ENTITIES (CLASSES, MODULES, FUNCTIONS, ETC.) SHOULD BE OPEN FOR EXTENSION, BUT CLOSED FOR MODIFICTION. This statement pretty much says it all, and naturally extends the Single-Responsibility principle: Classes (and functions, etc.) should be kept as simple as possible (having a single responsibility) and therefore should never have to change. Therefore, if you want to add functionality to your system you should add new code instead of changing existing one....

TDD and the SOLID principles (Part 1 – introduction)

Friday, August 26, 2011

Table of contents: Part1 – Indrocution (this post) Part 2 – SRP Part 3 – OCP Part 4 – LSP Part 5 – ISP Part 6 – DIP Part 7 – Conclusion   Mastering TDD is a process that takes time. There are many pitfalls that “newbie’s” fall into. IMHO the following 2 reasons are the main ones: Thinking about the implementation before writing a test. That is, writing tests that are coupled with the implementation instead of with the problem...