Test Driven Development (TDD) is a software development process that weighs on a short development cycle. The developer first writes an automated test defining the new feature or update, which fails at first, then write minimal code for the tests to pass, then refactor the code according to the needed standards. TDD is helpful in keeping the code neater, simple and bug-free TDD starts with designing and developing tests for every small functionality of an application. The test is developed which will specify and validate what the code will do. n the normal Testing process, we first generate the code and then test. Tests might fail since tests are developed even before the development. In order to pass the test, the development team has to develop and refactors the code, which means changing the code without affecting its actual behaviour. We usually follow the following sequences in TDD.
- Add a test
- Run all tests and see if the new one fails
- Write some code
- Run tests
- Refactor code
- Repeat
The simple concept of TDD is to write and correct the failed tests before writing new code. This helps to avoid duplication of code as we write a small amount of code at a time in order to pass tests. Test-Driven development is a process of developing and running automated test before actual development of the application. Hence, TDD sometimes also called as Test First Development.
In short, TDD is
- Write a test
- Make it run.
- Change the code to make it right i.e. Refactor.
- Repeat process.
Why use Test Driven Development
- Early bug notification.Developers test their code but in the database world, this often consists of manual tests or one-off scripts. Using TDD you build up, over time, a suite of automated tests that you and any other developer can rerun at will.
- Better Designed, cleaner and more extensible code.
- It helps to understand how the code will be used and how it interacts with other modules.
- It results in better design decision and more maintainable code.
- TDD allows writing smaller code having single responsibility rather than monolithic procedures with multiple responsibilities. This makes the code simpler to understand.
- TDD also forces to write only production code to pass tests based on user requirements.
- Confidence to Refactor
- If you refactor code, there can be possibilities of breaks in the code. So having a set of automated tests you can fix those breaks before release. Proper warning will be given if breaks found when automated tests are used.
- Using TDD, should results in faster, more extensible code with fewer bugs that can be updated with minimal risks.
- Good for teamworkIn the absence of any team member, other team members can easily pick up and work on the code. It also aids knowledge sharing, thereby making the team more effective overall.
- Good for DevelopersThough developers have to spend more time in writing TDD test cases, it takes a lot less time for debugging and developing new features. You will write cleaner, less complicated code.
