1.6. Test-driven development

Once you know how to write structured, maintainable, and solid tests with a unit testing framework, the next question is when to write the tests. Many people feel that the best time to write unit tests for software is after the software has been written, but a growing number prefer writing unit tests before the production code is written. This approach is called test-first or test-driven development (TDD).


There are many different views on exactly what test-driven development means. Some say it’s test-first development, and some say it means you have a lot of tests. Some say it’s a way of designing, and others feel it could be a way to drive your code’s behavior with only some design. For a more complete ...

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