Why Test-Driven Development Is More Useful Than I Thought

In software development, strong design habits are key to building software that is easy to understand and change. The blog post “Test-Driven Development: The Best Thing That Has Happened to Software Design” from Thoughtworks talks about how Test-Driven Development, or TDD, improves both code quality and design. This connects directly to what we have been learning in class about writing better, more reliable code.

Summary of the Blog Post

The post explains that TDD is not just about writing tests before coding. It is a way of working that leads to cleaner, better-organized software.

Writing tests first forces developers to think about what they want the code to do. It also leads to smaller, more focused units of code that are easier to test and maintain.

TDD also encourages better object-oriented design. Since you are planning behavior early, classes and methods tend to have clearer responsibilities. Another major point is that TDD makes refactoring safer, since a full set of tests can quickly catch mistakes.

Even though TDD can feel slower at first, the blog points out that it saves time in the long run by reducing bugs and making changes easier.

Why I Picked This

I picked this blog post because we have been learning about TDD in class, and I wanted to understand why it is considered such a big deal. Before reading this, I thought TDD was just extra work. This post showed me that it is really about designing better code from the start. Since TDD is common in real-world development, it made sense to learn more about it now.

Thoughts and Takeaways

One thing that stood out to me is how TDD helps you spot design problems early. If your code is hard to test, that is usually a sign it needs to be simpler. I had not thought about testing as a way to catch bad design, but now it makes perfect sense.

Another takeaway was how TDD makes refactoring less scary. In the past, I was nervous to change code that already worked because I was afraid of breaking it. With a strong set of tests, making improvements feels a lot safer.

Applying TDD

I want to start practicing TDD more, even on smaller projects. It might take some extra effort at first, but if it helps me write better, more flexible code, it is definitely worth it. Getting into good habits now will only help me later on bigger assignments and real-world work.

Conclusion

This blog post gave me a much better understanding of why TDD matters. It is not just about finding bugs, it is about building software that is better from the start. I am definitely motivated to practice TDD more and make it part of how I approach coding.

From the blog CS@Worcester – KeepOnComputing by CoffeeLegend and used with permission of the author. All other rights reserved by the author.

Overview of combinatorial testing

In complex programs, choosing valid test cases often means choosing from many different possible combinations of inputs to find the correct cases. Doing this could take an unnecessarily long time, slowing down the development process, and possibly causing some important cases can be missed. In the article, “Combinatorial testing: What is it, how to perform, and tools”, author Shanika Wickramasinghe explains the details of combinatorial testing, and how it solves the aforementioned problem.

Combinatorial testing involves using multiple combinations of variables for testing, with the goal of this being to verify which/how many inputs of test data, with this information then being used to design future tests. Some of the benefits of combinatorial testing include a larger coverage of possible test cases than normal testing, since multiple inputs are used, reduces the cost and effort of the testing process through the fact that it’s a faster method of testing, and avoiding redundancy, as combinatorial testing ensures that the same cases aren’t tested multiple times.

To better understand how combinatorial testing works, lets take a look at the author’s example. Say we’re trying to test a username and password functionality, and we decide we’re using combinatorial testing for this. Instead of each test case only including one username OR one password, like what would happen if normal testing was being used, each test case includes 1 username and 1 password from a pool of multiple usernames and passwords. For example, let the tested usernames be User1, User2, User3 and let the tested passwords be PW1, PW2. Then, test case 1 could be testing User1 and PW1, then case 2 would test User2, PW1, then case 3 would test User3,PW1, and so on. By doing this, every case would be covered with only 6 test cases, with the same case never being covered twice.

Other types and ways of implementing combinatorial testing are available as well. For example, the example listed above would be an example of manual combinatorial testing, where cases are manually selected from the pools of parameters, where in automated combinatorial testing, software or scripts are used to automate this process and create many test cases automatically. This is especially beneficial if there are many possible inputs, and manually picking each case would be too time consuming.

From the blog CS@Worcester – My first blog by Michael and used with permission of the author. All other rights reserved by the author.

Recognizing the value of different types of unit tests

Unit testing is a very useful and secure way to stabilize the development process, but despite that, some developers forgo the testing process altogether. In Gergely Orosz’s blog entry, “The pyramid of unit testing”, he covers the relationship between the time it takes to notice the benefit of certain types of unit tests, and the experience of the coder designing the tests. For example, a coder with limited experience may look at a code body, see there are no obvious problem cases to be caught by unit testing, and forgo the process, while an experienced coder may see the same code and choose to design tests for it for reason that aren’t as obvious, and that are more based on experience and intuition.

Gergely details 5 different tiers of the Pyramid of Unit Testing Benefits, with the tiers lower on the pyramid listing benefits that can be noticed immediately, and tiers higher showing benefits that are only noticed in a later stage in development. The lowest tier are the benefits offered by tests designed to validate code changes. These tests are purely designed to validate recent changes, and make no attempt to catch future cases that might not be a problem now, showing an immediate benefit compared to not testing. The next tier up is the benefit of separating concerns in your code, which serves to somewhat force the coder to write clean code, since if a code is to be testable, that usually means that dependencies are declared upfront, leading the code to have an easier to follow structure. The next tier is the benefit of having an always up to date documentation. Well written tests can serve as useful documentation for code, and, unlike documentation of implementation code, these tests won’t get out of date. The second to last tier is avoiding regressions. If changes are made to a code body with no unit testing, than regression and conflicts are more likely to be introduced compared to a code body with tests. Designing tests helps avoid this by catching these regressions/conflicts before they become problems. The highest tier of the pyramid is using tests as a refactoring safety net. While testing is useful for validating small changes, it’s equally as useful for providing a stable environment for refactoring. When required to make large scale changes, a developer is more likely to be comfortable changing a code body with a large amount of coverage over many unit tests, rather than a code body with no means of catching problem cases.

From the blog My first blog by Michael and used with permission of the author. All other rights reserved by the author.

My Look into QA Testing

Hello, Debug Ducker here and this time I got interested into learning about QA testing. This sudden feeling of wanted to know more about this field came from my time spent watching online entertainment. In a lazy afternoon I decide to watch a gaming podcast, and found out that one of the host of the podcast was QA tester and worked on several games. His stories about his time in the business intrigued me a lot and made me do further research on what the job of being a QA tester requires. What I found is very interesting and hope you find it interesting too.

Let’s start off with what QA testers exactly do. QA testers is to make sure a product meets quality and legal standards and how they go about it is by using automated test with the purpose of making the program malfunction of break. This helps development teams as they find the issues that need to be address while still focus on the development of the product.

What I found interesting is that QA testing is that they perform a method of testing known as black box testing. They can’t see the code but still test its functionality. In my time studying software testing I was thinking of the possible reasons on to why would I test something that I can’t see. I realize now that if you can’t see the code you don’t have any preconceived notions on how it should function. If you had someone else, like a QA tester test it they would attempt to break things easily as they don’t ahve the idea of what the code base looks like. They are the unbiased viewer. Which can help a lot. I remember when testing for software there would be this one thing I didn’t account for based on my own assumptions and my code. Which lead to many annoyance and headaches.

QA testing is a very important aspect of software development. It helps find issues that can be missed and can keep a project manageable and focus when there is an entire team focus on testing. QA testing can save a lot of time too which can be very important for a project.

Maybe one day I can tell you more about the podcaster and his foray into QA testing as he has a lot of interesting stories to tell.

Thank you for your time have a great day.

From the blog CS@Worcester – Debug Duck by debugducker and used with permission of the author. All other rights reserved by the author.

Test-Driven Development

Hello! Welcome back to my next blog post. This post is about Test Driven Development, also known as TDD. I used this article to do some research on it: Test driven development: What it is and the benefits of using it

I chose this article because it goes into further detail about what we already learnt about in class. I chose this topic because we just went over it in class recently, and we also had a homework assignment on it. At first, I was very confused on what to do in the assignment, and I had no idea what I was supposed to put in the testlog file. But by the end of the homework assignment, I kind of understood everything more, and realized that the testlog file was just meant to help me organize my test backlog, and make all of my commits with notes left behind. It took me a lot of time to come to these realizations, but once I did it helped me a lot.

This article talks about something we briefly went over in class, called the “red-green-refactor development cycle.” What this means is that first you want to write a test, which you already know is going to fail – This is the red part. Then, you want to write very simple code; Just enough to make sure the test you wrote passes – This is the green part. Finally, you want to refactor your code, and make sure not only the first test passes, but also all of the previous ones as well. Refactoring is probably the most difficult part of the process, since the other two are sort of bare minimum procedures.

I was instructed to do this in the homework assignment, but with Test Driven Development, you are supposed to only do one test at a time. I think this is smart because sometimes you can get ahead of yourself or get lost while you are trying to make multiple tests pass at the same time. Sometimes with coding I feel like you can make more mistakes trying to be fast, which ultimately slows you down. While if you take it step by step, it actually could end up being quicker than if you are rushing and not being careful.

Overall, TDD is a very interesting topic, and it was helpful that we not only went over it during class time, but also had a way to practice this with the Kata homework.

From the blog cs@worcester – Akshay's Blog by Akshay Ganesh and used with permission of the author. All other rights reserved by the author.

How Test-Driven Development Changed My View on Coding

The article I selected is titled What is Test-Driven Development? It explores TDD, which stands for Test-Driven Development. A software development methodology where tests are written before writing the actual code. At first, this idea sounded very backward to me, especially as a student still learning how to code. Originally introduced by Kent Beck in the 1990s, TDD follows a specific cycle: first, you write a failing test for a small piece of functionality. Next, you write the minimal amount of code needed to make that test pass. Finally, you refactor the code while continuing to pass all the tests. This method aims to create reliable and well-structured code from the very beginning.

I chose this article because while working on the TDD assignment for class, I found myself very confused about why the process was designed this way. It felt unnatural to write tests before even having code to test. After reading a few articles, including this one, I learned that the main purpose of TDD is to reduce the amount of time spent debugging and to automate testing early. It helps ensure that the code behaves correctly as new features are added, reducing bugs and saving time later.

After practicing more during the assignment, I began to see the benefits firsthand. I enjoyed the process once I understood it better, even though there were moments when I had to refactor my code multiple times to make all the tests pass. One important takeaway from the article was how TDD encourages continuous improvement. As developers write more tests, their code quality naturally improves over time. I also learned that TDD plays an important role in Agile workflows, pushing developers to prioritize testing before writing large chunks of code. This mindset shift promotes creativity, collaboration between developers and QA testers, and reduces technical debt, making it easier to maintain and update code in the future.

This article and topic really changed how I view software development. It showed me that TDD can be both a creative and collaborative process rather than just a strict set of rules. I now plan to apply TDD practices in my future career. By writing tests first, I can better organize my development process, catch issues early, and build more reliable software. Exploring this topic helped me overcome my confusion during class and appreciate why Kent Beck created this approach in the first place.

Reference:
Moore, Paul. “What Is Test-Driven Development?” Scrumalliance.org, 2023, resources.scrumalliance.org/Article/test-driven-development.

From the blog CS@Worcester – CodedBear by donna abayon and used with permission of the author. All other rights reserved by the author.

Learning JUnit 

In the article I selected, the topic of JUnit, a popular Java testing framework, is introduced and explained. The article simplifies JUnit for beginners or those who have never used it before. It discusses key features such as assertions, test runners, test suites, and reporting tools. The article is divided into several sections, including an overview of what JUnit is, how it functions, the different types of testing it supports, and the key benefits of using it. It also provides a step-by-step guide on how to download and set up JUnit, making it an accessible resource for new learners.

Before taking this class, I barely knew anything about JUnit. As I read through the article, I learned that JUnit is part of the xUnit family of testing frameworks and is primarily used for automating unit tests in Java applications. It can also support other types of testing, such as functional and integration tests. One of the biggest takeaways for me was understanding the features that make JUnit so effective: assertions for verifying test results, test runners for executing tests, test suites for grouping tests together, and reporting tools for easily spotting problems. I also learned why using JUnit is important not only because it helps developers write more organized and readable code, but it also improves error detection and correction early in the development process. This ultimately boosts the efficiency of QA testers and software engineers.

I chose this article because we recently discussed JUnit in class, and I wanted to deepen my understanding beyond just what was covered in lectures. As someone studying to become a future software engineer, I realized that knowing how to write effective tests is just as important as writing code itself. Testing frameworks like JUnit ensure that applications behave as expected, making them more reliable and easier to maintain over time.

Reflecting on what I learned, I feel much more confident about incorporating unit testing into my future projects. Learning about assertions and test runners especially helped me see how testing can be integrated smoothly into the development process rather than being something added at the end. Going forward, I plan to apply this knowledge by writing unit tests alongside my code from the beginning, which I believe will make me a more efficient and thoughtful developer. Overall, this article not only expanded my technical skills but also shifted my mindset about the importance of testing in building quality software.

Reference:
Abhaya. “JUnit: A Complete Guide – Abhaya – Medium.” Medium, 9 Jan. 2024, medium.com/@abhaykhs/junit-a-complete-guide-83470e717dce.

From the blog CS@Worcester – CodedBear by donna abayon and used with permission of the author. All other rights reserved by the author.

The Next Phase: Integration Testing

https://www.geeksforgeeks.org/software-engineering-integration-testing/

Amongst all of the phases of testing and quality assurance, one of the most critical, and arguably the most satisfying, is integration testing. In an article posted to the geeks for geeks website, the author dives into the importance of this phase that comes after all unit testing has been completed. The article notes that this software testing technique focuses on verifying the interactions and data exchange between different components or modules of a software application. It helps to identify and resolve integration issues early in the development cycle, thereby reducing the risk of more severe and costly problems later on.

I chose this topic because I wanted to have a better understanding of the individual components that make up the complete software testing life cycle. For our final group project, we chose to create a lesson plan around integration testing and system testing. Part of my portion of the project is developing a module based around integration testing; this article gives a comprehensive overview on this topic.

The biggest takeaway from this article was about the different methods of integration testing. I was not aware of the different approaches that you can take when doing this type of testing. Big- bang testing is a method that is simple to implement because it combines and tests all modules at once. However, this is not the most efficient when it comes to larger systems because it can be harder to diagnose where a problem has stemmed from. Bottom up testing tests component integration starting with the lower level modules and working their way up while Top-down testing does the opposite. Both come with their own set of advantages and disadvantages but most can be mediated with mixed integration testing; mixing both bethods together.

At first impression, the article made me draw connections from this phase of testing to how I have developed and tested things in the past, especially my personal website. I feel like going from unit testing to integration testing to system testing is an inherently human way of developing anything. When I was building my personal website, I was learning CSS and HTML as I went along. I found that I naturally performed integration testing directly after testing individual components of my site. It was during this testing phase I was able to get the first feel of how my site, webpages, links, and API’s worked together; it was the one of the more satisfying parts of my web development journey. Moving forward, now having a better understanding of this phase of testing, I will try to implement a more systematic angle of integration testing in future projects being sure to utilize the different methods that were outlined in this article.

From the blog Anna The Dev by Adrianna Frazier and used with permission of the author. All other rights reserved by the author.

Test Driven Development

This past week we worked on test drive development which was very difficult for me do to me being used to working with only source code first then writing test code. This new approach in my head was fairly easy, but when I went to code it, I was struggling. I believe part of this struggle was due to me not thoroughly writing out my test cases and taking the time to fully understand what I was doing. I ended up doing better on the testing for the homework than the activity I believe because I took a step back to understand and read more in depth into the five steps provided. I decided to also read more on another website (sourced down below) about test driven development, which this website went into more of the process of it and how the cycle works. It explored the history of it as well as the advantages and disadvantages.

These advantages included how writing the tests first provided constant feedback to the developer as well as always meeting the requirements more in depth and not having unnecessary tests or codes. This helps developers decrease production time in some scenarios due to only having to write the tests than source code to only specially pass that one test and if needed down the road to refractor code the developer can do so as well, but they will know what went wrong and reach their conclusions much quicker. The disadvantages spoken about are increased code volume which can be a pain currently or down the line when the code is going to be refactored or maintenance. Also, a huge disadvantage that can lead to multiple issues is false security from tests which some developers will go in and assume since one test passed, they do not need to make more. I believe personally for larger applications test driven development is not the best idea due to ever growing projects which will require lots of testing and can only be written after the source code to ensure they all work together rather than individually because some methods rely heavily on other methods.

The great thing about test driven development though that I learned and enjoy is finding bugs much earlier on. It helps me quickly go back and refractor my code for the test to pass but as stated previously it has its advantages and disadvantages. Overall, I had a hard time with it because I have never heard of it until now, but reading more about it I understand the main concepts of it. The activities in class did help discussing with the team as well as the homework, but the thing that confused me about the homework was the log since I usually don’t write logs on how and what test I am going to do because I base it on the source code. Overall, it was a great experience, and I am glad I was exposed to it so I can try it more on my free time and see how it is used in the real world.

Source: What is Test Driven Development (TDD)? | GeeksforGeeks

From the blog Cinnamon Codes by CinCodes and used with permission of the author. All other rights reserved by the author.

Favor real dependencies for unit testing

URL: https://stackoverflow.blog/2022/01/03/favor-real-dependencies-for-unit-testing/

Mark Seeman brings us an interesting idea about which dependencies should be used during testing. In his article Favor real dependencies for unit testing, he explains that not every dependency necessarily helps you develop your tests. His main point concerns the use of dependencies that generate some kind of fake implementation of your methods in order to allow you to test them. One great example of this is Mockito, a widely used Java library where you can ask the tool to mock an entire class implementation. Although that sounds completely reasonable at first glance, what could be one issue that Mark is possibly missing in his argument? I would say that he is missing the reason why developers often rely on mocks and stubs in real-world development scenarios.

The main reason someone may choose to use mocks and stubs is more related to collaborative group work rather than projects handled by a single developer. In group settings, such as when working on a complex system like a hotel booking website, developers are usually assigned to different components or features of the system. For example, imagine a situation where you are working as a developer on such a project and are responsible for the Bookings class, while your teammate is assigned to the Suites class. Both of you have been making progress on your respective parts, and now you want to start writing tests to ensure everything functions as expected.

However, if any of your methods rely on a function that your teammate has not yet implemented, you could run into difficulties. Without the other function available, you might not be able to fully test your own code, even though your part is technically complete. This could lead to a development bottleneck, preventing you from moving forward until the rest of the system is ready.

To solve such a problem, one practical solution is to use libraries like Mockito. These tools allow you to create a mock version of your teammate’s class or method, enabling you to continue writing and running tests without delay. As explained earlier, Mockito generates fake implementations that simulate the behavior of the real components. This makes it possible to isolate and verify your own code independently.

Mark’s point is valid in scenarios where a developer is solely responsible for both the implementation and testing of all related methods. In such cases, using real dependencies like database fakes or stubs may be more effective. However, in collaborative environments, mocking libraries are essential tools that support parallel development.

This article surprised me with its perspective and application. As I’ve learned in class, the use of mocks allows developers to test features that haven’t been implemented yet adding a useful layer of abstraction. I believe that such libraries are not meant to stay in the codebase permanently but rather serve as temporary scaffolding—tools meant to be discarded once the full system is in place.

From the blog CS@Worcester – CS Today by Guilherme Salazar Almeida Nazareth and used with permission of the author. All other rights reserved by the author.