A Detailed Guide to Test-Driven Development
Test-driven development (TDD) is an essential software development technique employed in agile project management, in particular Extreme Programming.
What is it?
Test-Driven Development is the practice of writing tests before writing the code being tested. The process involves rapidly iterating the following steps: writing test code for the desired functionality, running and failing the test, writing actual code to make the test pass, then refactoring the code for optimization.
Why is it important?
TDD is crucial because it helps ensure code correctness, encourages simpler design and promotes understanding of requirements before a single line of code is written. The good test coverage reduces the risks and costs associated with code changes in the long run.
How does it work?
The basic work flow of Test-Driven development is a cycle of Red, Green and Refactor. Red indicates that the written test cases fail, Green indicates passing of the test cases when the actual code is written, and Refactor is the phase where code optimization is done without altering external behavior to remove any redundancy.
Exam Tips: Answering Questions on Test-Driven Development
Understand the TDD cycle thoroughly, be prepared to provide examples of how TDD can improve code readability, maintainability, and trustability. Remember the main principle behind TDD i.e., writing test cases before developing software. Do not forget to mention the benefits of TDD when answering exam questions. Practice diagramming a TDD cycle, as visuals can often help in conveying the methodology.