How does Test Driven development benefit developers?

Test driven development (TDD) as a process has proven to be a boon for developers time and again. Businesses tend to change rapidly with the time and so does their requirements from the software that they are using. If we develop these software products using the traditional development methodologies, it is obvious that later it will be more difficult for us to maintain them as requirement changes. If you suggest making changes to the existing model developed using traditional method, it might create havoc in unpredictable ways. As a result of these consequences, organizations often don’t go for modification of the existing software as it might hamper their productivity and effectiveness. But this is no problem for companies who have developed their products using TDD. This is so because it is like a continuous integration model in which testing modules are added. Then it becomes easy for the organizations to make modifications to their products, without fearing any breakdown.

First benefit of TDD to developers is that it is easy for them to maintain the software by virtue of its extensibility and flexibility. Since both testing and development go hand in hand in TDD at the lowest level, it guarantees testing of every single logical piece and can even be changed. Once the development is done, the application is tested once again with thousands of tests. After making a change to the application, associated tests are run to see if there is any impact on the other parts of the application. With this approach there occurs no problem in modifying the existing legacy applications. Apart from benefiting developers, this has benefits for organizations seeking growth by making it easier for them to update their systems.

The codebase is streamlined along with test coverage which is unparallel. In TDD, writing a test first before writing code is mandatory. That is how it provides unparalleled coverage. Further, regression testing and refactoring make the code as minimal and economical as possible. This plays a big role in streamlining the codebase. If for a functionality there is no use case, the test is not written and no code and thus there is no growth in the codebase. This is also another reason behind easy maintenance.

TDD provides a clean interface throughout the development process. Since the tests are written first, the APIs thus produced are from the perspective of an API – user. That’s why it is very easy to use these APIs when compared to the APIs written by programmer’s perspective.

The code refactoring process is central to the success of TDD and makes sure that the codebase is strengthened preventing the software from getting outdated and monolithic.

TDD aims at improving the code and is particularly useful in the following:

> Addition of new feature or functionality: With TDD the programmer feels confident in changing part of a large application (even otherwise the programmer might feel confident but this feeling may not be shared by other stakeholders). If it wasn’t flexible, then we would be adding functionality to the application but without any proper integration. This would have definitely caused many problems.

> Changes in the technical infrastructure: Developers are always thinking of making technical changes to the code for increasing its elegance and make it more extensible.

The use cases used in TDD are actually tests which can be used by the other developers as examples of how the code works and how it can be used. Thus TDD provides executable documentation. Updating the software without any painstaking efforts has been possible because of TDD.

An organization can be successful only if it embraces the changes and makes improvements. Test driven development makes all this possible with its extensability, maintainability and flexibility.