The Value of Testing

The blog post How Do I Know My Tests Add Value? by AutomationPanda discusses the value of proper testing. The author brings up the common issues that sprout from use a bug-fixed count as a metric for successful testing, and highlights why testing is important and can help improve development.

Testing is important because it validates that your program is working as it is expected to. Well-written tests with the proper amount of coverage give you information about your program and whether any changes need to be made. A passing test indicates correctness and that your program is working as expected. A failing test points out a bug that needs to be fixed and helps highlight weak parts of your code.

The absence of testing might not necessarily lead to bugs, but we all know as programmers that even when it seems your code is running exactly as you intended it to, logic errors can happen and sometimes things weren’t written with every situation in mind. When testing is in being implemented, developers are accountable for the code they write, and must think carefully about the issues that may arise.

Tracking bugs isn’t necessarily effective because it encourages testers to find issues even when there may not be any. All tests passing is still good news and a sign of progress, even if it just means you are doing everything right. Enforcing bug quotas and forcing testers to find issues means they will expend effort looking for things that aren’t there and nitpicking small issues rather than writing more tests or making sure they have good coverage, which are far more effective and finding issues in your code.

At the end of his post, the author suggests some different metrics to use: time-to-bug discovery, coverage, and test failure proportions. All of these serve as much more accurate and effective measures of determining whether your testing has value. Whatever metric you use, it is important to think about why you are testing and whether you are doing it in a way that tells you something about your program.

Model-View-Controller

On his blog, Mikke Goes takes the time to explain the Model-View-Controller design pattern in his post What is the Model-View-Controller (MVC) Design Pattern?. He uses the analogy of an ice cream shop to describe the different functions of the components. The waiter is the view, the manager is the controller, and the person preparing the ice cream takes the role of the model. Together, when a customer makes an order, they each can perform their responsibilities and successfully handle the customer’s request.

The Model-View-Controller design pattern separates the components of your code into sections that divide logic from interface. Keeping the functionalities separate from each other will make your application easier to modify in the future without running into issues. Each of these different groups has a different responsibility when it comes to the application and how requests are handled.

The view consists of the parts of your application that your user will see and interact with. It is not very smart, only outputting the information given to it by the controller. The view helps users make sense of the logic behind your application and interface with it.

The model is the opposite, dealing with all the logic and data manipulation behind wheels of your application. The model responds to requests by processing any data in the necessary ways and giving it back to the controller in a form the view can understand.

The controller handles the communication and interaction of these two. When a request is put in through the view, the controller brings this to the model, and takes the model’s output back to the view to be displayed. It is a middleman that helps connect the two other layers of responsibility.

The Model-View-Controller design pattern seems like a pretty simple design pattern to comprehend. All of the components are divided by responsibility and the program is written with this in mind, making sure that only certain components handle tasks that are within their category. In terms of our projects, the front-end would amount to the view and the back end to the model, with the typescript file functioning as the model. It seems like the development of web applications would sort of naturally fall into this design pattern.