Dominika Nykiel, Aleksandra Spilkowska
Table of Contents
Why do we perform software testing? To find defects. That is the simple, or even simplistic, answer. We want software to run smoothly in a production environment and perform as expected. Seems pretty straightforward, doesn't it? But it's always worth double-checking when quality is at stake! There are crucial steps in a software development life cycle (SDLC) that, if followed, make the product reliable and more well-rounded. Before moving on to the importance of testing, let's take a quick look at different them.
Different types of software testing
Typically, if testing is implemented in the SDLC, it would be divided into several layers. The first would be unit tests which are usually simple and fast, as they are only performed on a small module (unit) or a portion of the code. The advantages are speed and simplicity, as the developers are quickly alerted if a unit test fails so that they can review the part of the code that does not work correctly.
Once individual units have been created and tested, it's time to perform integrated testing, which tests their interfaces. Individual modules can then be combined and tested as a group. This layer of testing determines how larger parts of the software work together and how they interact with third-party tools or APIs, if applicable. It may be simple or quite complex, depending on the software itself. It is advantageous if several developers are working on different units or changes were made to one of them.
The best practice is test along as more modules are created. If testing starts when the system is already practically integrated, and defects are found (and, let's face it - likely there are some), finding why and where they are in the software may be especially difficult due to the multitude of interactions and interfaces.
Finally, end-to-end testing focuses on the performance and capabilities of the software as a whole, including the entirety of tasks it can do. The goal is to simulate what actual use would be like from start to finish. It validates the main, as well as the interconnected systems.
Interaction accuracy is ensured at this stage to ensure consistent user experience across multiple platforms, devices, and environments. Moreover, end-to-end testing increases test coverage, which helps build confidence in the success of the testing process.
That is extremely important nowadays, as software becomes increasingly complex, often relying on an intricate network of subsystems and layers. In such cases, the system's stability depends on its parts' functionality. The definite downside of this approach is the cost. The all-encompassing premise of end-to-end testing and the overall monitoring required make it an extremely time-consuming test method. Tracing a bug can take even more time if found at this point, and tracing its cause can take even more time.
After this brief overview of layers of testing, let's move on to what particular advantages it may bring.
Importance of software testing and advantages
In today's fast-paced technological landscape, software testing has become an essential aspect of the software development process. It involves the evaluation of a software product or application to ensure that it meets the specified requirements, functions as intended, and is free of errors or bugs. In this section, we will explore the importance of software testing and the benefits of testing.
Saving time and money
Not only does money make the world go round, but it also tends to be one of the most important factors people consider when making decisions about purchasing or investing in developing software. If testing is neglected and there is a bug in the system (practically a certainty), it will need to go back to the developers to be fixed, which means more time and energy being put into the product. And, as the old aphorism says - time is money. Particularly in software development, more time undoubtedly equals extra cost. The faster the testing starts, the less likely it is possible that an evident defect will occur during end-to-end testing when it is considerably more expensive to fix.
Ensuring product quality
Detecting defects and errors early dramatically reduces the risk of insufficient software quality. Naturally, the last thing one would want is for customers to find bugs in the software. Worse yet, the bugs can potentially make using the application – and thus making money on it – impossible. Testing, understood here as a synonym for quality assurance, relates to quality control through the SDLC and is meant to prevent such things.
Testers can be involved in requirements reviews or clarifying user stories at the earliest stage. The stories help detect defects. Identifying and fixing these defects reduces the risk of producing incorrect or untestable software features. Close cooperation between testers and software developers at the design stage allows both parties to better understand the system design and how it should be tested. The better knowledge of the subject, the better the result. To ensure product quality, the tester must be aware of the risks of defects in the code and potential failures.
Risk in software testing is the possibility of an event that would have undesirable consequences in the future. The risk level is determined by estimating the probability of such an event occurring and its potential negative results. Analyzing risk can be used to plan testing. The goal is to identify the areas that need more attention—focusing on those reduces the probability of an undesirable event occurring (or at least helps manage its impact). The risk-based testing approach contributes to risk mitigation and provides stakeholders with valuable information on identified risks. They may then decide if the issues need immediate attention. When such an analysis is performed early, it can contribute to the entire project's success.
Product quality is intrinsically linked to customer satisfaction. Banking on cheap products barely serving their purpose is a short-lived business strategy. Quality is the way for those who want to establish a reputable brand and attract loyal software users.
Anyone who has ever managed a large-scale project can attest that assessing a client's needs may save a lot of headaches later. Some products must fulfil a set of requirements based on agreements, laws, norms, and standards. Proper verification helps ensure that. Checking that those requirements are met prevents putting potentially unusable software into the user's hands, which can later prove costly, not to mention the loss of intangible assets, such as the client's trust. In the long run, testing doesn't just prevent failures and helps establish the product as secure, reliable, and easy to use, subsequently attracting more clients.
Last but not least, testing makes the product more secure. For this reason, security testing is a crucial aspect of software testing. It is meant to find weaknesses and vulnerabilities in the software to protect it from potential threats. Why is that so important? First of all, people are more likely to use trusted products. Secondly, security failures can damage the company's image and income.
As the existing laws in the European Union protect personal and sensitive data, uncontrolled leaks can result in millions in fines and penalties. Security testing should ensure that the identity of those with access to personal information is adequately verified. Data should be available, correct, and safe from accidental leaks and nefarious attacks. In extreme cases, security breaches can lead to the whole software not working, which can mean no business continuity and high revenue losses. Like most types of testing, finding a defect typically costs more if done later and even more (fines, loss of credibility, etc.) if done improperly or skipped altogether.
Considering its crucial role in ensuring flawless system performance, testing should be considered a necessity, not just an option. The negative consequences of passing faulty software to users are evident. Apart from their base task of finding defects, tests also have an instrumental significance for the SDLC, as they may contribute to improving software quality as a whole.