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What is Test Driven Development (TDD)?
My friend told me TDD is not about testing, that it's all about the design. I don't understand why he would think that.
what do you think TDD is all about ? what are its advantages ? disadvantages ?
I've found it impossible to use TDD in some projects of mine.
It is a style of development where you develop tests before you write the code.
The theory is that doing development in this order will help you define EXACTLY what any given piece of code should do with a specific set of input.
That functionality should be clear and tests developed first. Once tests have been developed, you can begin coding to those strict specifications. With tests already in place, you already have immediate feedback if your code meets the spec or not.
The obvious downside is time. You have to spend the time up front writing good tests for this methodology to work.