What is test-driven development?
Test-driven software development or TTD is the common software development practice where each functionality goes through specifically designed test cases. In this practice, the code is rewritten after every failed test, till each functionality as the code in whole is bug-free.
Such a technique prioritizes flexibility and agility, while also helping simplify the code and make it easy to work with at any stage of the development.
Test-driven development benefits
Here are the expected benefits of test-driven development:
- Lower defect rates: TDD means a slight increase in effort during the initial development stages. Yet, it leads to a noticeable reduction of flaws and errors throughout the building process. Any errors will be detected and fixed as soon as they arise.
- Higher quality: It’s believed that test-driven development methodology results in the overall higher technical quality of the product, with little to no chances of errors. Such a method ensures a more cohesive and concise operation, promising easy use and high capability.
- Greater flexibility: Such methodology allows more opportunities for frequent testing and change implementation. For instance, businesses can scale applications for their needs with little effort and at a low cost.
- Easier maintenance: TTD allows for the easier location of any errors. The “divided into blocks” structure gives fast and easy access to any coding area in need of improvements. So, any bugs or improvements can be performed on a short deadline.
- Higher transparency: This practice is based on transparency. It means easy and open communication among all team members. Thus, the development process goes faster, more efficiently, and accurately, with little chances for miscommunication or human errors.
What are the steps of test-driven development?
The test-driven development process has five steps. They are a part of the “Red. Green. Refactor.” flow.
So, the TDD starts at “Red:”
- The flow starts at the feature request. Developers need to read and process the given request. Overall, every app feature will have a test written for it, to verify its proper work.
- Next, developers need to run a test for the given request. It will result in a failure, as no new code was written. Failing a test shows that it’s working.
- Following the failed test, code must be written. The code should write the requested feature and implement it. The writing at this stage can be very simplistic, as its main goal is to pass the test. At this point, developers are in the green sector of the flow.
- Finally, the team runs the test again, only this time it has the newly written code. If the feature performs as it was intended, it passes the test, completing the green stage.
- Lastly, the refactoring stage is where developers can adjust their code and move to the new cycle with a new feature. The flow continues until the app is complete.
Such thorough steps improve work efficiency and enhance the product’s quality. However, they are only recommended with large, complex projects that start from scratch, as TTD requires an increased amount of effort and time.