in reply to Test Driven Development Workflow
In "TDD" as the latest buzzword methodology, writing the tests first is what it means. Why would you need to do that? Because it substitutes for formal requirements. Perhaps it is a formalization of the "acceptance criteria" in an Agile process. Also, different teams may be writing and performing tests, in contrast to those writing the actual code.
More generally, having "critical test cases" defined as part of the design document doesn't mean you need running code for them. It just helps communicate the design and limitations. Test Cases might actually be Use Cases and communicate how the component will be used and what it's good for.
When doing it all myself, I've found that writing the code and (actual) test code together works well. I'll write the constructors and test them. Write a particular tightly-related group of functions and then test them. Repeat until done.
So ask yourself what needs to exist at what stage in the process, and make sure you have a good reason why. What is your process?
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