TDD and the SOLID principles (Part 4 – LSP)

Thursday, September 22, 2011

This is the 4th post in the series about TDD and its relationships with the SOLID principles. Here are the links to the other parts: Pat 1 – introduction Part 2 – SRP Part 3 – OCP Part 4 – LSP (this post) Part 5 – ISP Part 6 – DIP Part 7 – Conclusion The LSP (Liskov Substitution Principle) The principle (originally stated by Barbara Liskov in a more academic fashion), states that: FUNCTIONS THAT USE REFERENCES TO BASE CLASSES MUST BE ABLE TO USE OBJECTS OF DERIVED...