Test-driven development is a programming approach is compulsory for you to write real code and automated the test code together. This confirms that you test your codeand permits you to re verify your code fast and easily, since it's automated.
TDD will travels around a small iterative development cycle that goes something like this:-
While writing the automated verification code, you must consider into account all possible inputs, errors/mistakes, and outputs. This way, your brain is not confused by any code that's already been written.
Later, you can start programming. Since there's already an automated experiment, as long as the code disappoints it, it means that it's still not organize. The code can be set until it passes all insistence.
Once the code passes the test, you can then start polishing/clean it up, via restructuring. As long as the code still accepts the test, it means that it still works. You no longer have to worry about the alterations that founds new bugs. Begin the whole thing over again with some other technique or program.