Test driven development, or TDD, is a coding style where writing the testing code precedes writing the actual code. This is so that the functions and components of the code are checked early on to have intended and predicted behaviour. Here are some of its advantages:
Leads to greater modularisation in code and design - this is as when writing tests, we write tests to test different sections of the overall system, therefore we focus more on the high level breakdown, initially, then on the lower level implementation
Higher test coverage - as you are writing the tests before you write the code, you won’t be missing out on tests for any of your code sections, therefore more of the code overall will be covered by the different tests
Reinforces notion that tests are vital to a system, and not just something that is quickly appended at the end, as you are focussing on testing simultaneously with development throughout the whole process
It simplifies documentation - as the tests explain and cover different components of a system, they also therefore assist with documentation and explaining the design of the code as well
Maintenance and refactoring is easier - this is as many of the tests are already written, you won’t need to worry as much about breaking current code when introducing modifications or new code
It’s like building a solid foundation before constructing a house - makes total sense! Plus, having tests right from the get-go ensures you’re not missing any crucial checks in your code
how do developers typically approach writing tests before writing the actual code? Do they start by outlining the expected behaviour of the functions and components and then create tests based on that?
Just wonder, how might implementing TDD impact the overall quality and stability of software projects, like reducing bugs and improving maintainability over time?
That’s a comprehensive overview of Test Driven Development (TDD) and its advantages. It’s fascinating how TDD promotes a more structured and systematic approach to coding, leading to better-designed and more maintainable software.
I’m particularly intrigued by the point about simplifying documentation through tests. Could you elaborate on how exactly TDD assists in documentation and explaining the design of the code? It seems like an interesting aspect to delve into further.
Yes, that’s typically how it would be done. Before writing any code, developers plan extensively, which typically includes a class diagram, where we also define the what the functions of the different classes, would do. Then, knowing what each function does, we would write tests to check that the function’s output, once we write the actual function, is what we would expect it to be.
By having a clearer vision of how the code is supposed to function, particularly what the program’s data flow is supposed to look like, we ensure that each section of code is doing what it is supposed to be doing. So, once we actually write the code, we know exactly the output of each function, including how it fits in with the other function, hence we can just focus on implementation.
When you write the tests, you need to see how the different functions and components of the code fit in and work with each other. Therefore, by knowing how the functions interact and communicate with each other, you have a clearer image of the structure of the code. This helps you when writing the documentation because you already have a much clearer understanding of how the code functions and achieves the desired result, thus you can explain it more easily and clearly in the documentation.
