Test-Driven Development

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Test-Driven Development is a method to construct software that focuses on writing automatic tests for a system’s features before writing the code for the system itself. 

What is Test-Driven Development?

Test-Driven Development, or TDD, is a way of developing software with automated tests written before the actual code.  More traditional software development employs tests that are often written after the actual code has been developed. However, with TDD, the developer writes the tests first and then writes the code to pass those tests.

The process starts by defining a requirement or feature that needs to be implemented. The developer then writes a test case that defines the expected behavior of that requirement or feature. Once the test case is written, the developer runs the test, and it fails because no code implements the functionality required by the test case. 

Next, the developer writes the minimum amount of code necessary to pass the test case. Once the code is written, the test case is run again, and if it passes, the developer moves on to the next test case. If the test fails, the developer makes changes to the code until the test is passed.

In essence, the process of writing tests first and then the code to pass those tests is repeated throughout the development cycle, with the developer adding more test cases to cover different scenarios. The goal is to write code that passes all of the tests, ensuring that the desired output is correct and as intended.

Why Use Test-Driven Development?

There are several reasons why developers use Test-Driven Development (TDD) as their software development approach:

  • It helps identify bugs and defects early in the development process, allowing developers to fix them before they become more complicated and costly. As a result, it  improves the overall quality and reliability of the software.
  • The strategy can minimize time, resources, and money in the long run. Since each new code is first tested and then implemented, it leads to fewer bugs and the need for frequent manual testing.
  • This approach encourages developers to write modular and well-organized code by forcing them to think about the desired functionality and behavior of the code, which leads to better design decisions and more manageable code.
  • The method promotes a faster and more iterative development cycle. Because TDD focuses on writing tests and code in small increments and continuously verifying that the code works as intended, it leads to more efficient and effective development processes.

Test-Driven Development and Incredibuild