Software Testing Methodologies – [Detailed Explanation]

If you’re a developer, you know how difficult it is to write clean code in one go; it sounds impossible, right?

Well! It’s not humanly possible to code without breaking it at least once or twice; after all, we’re bound to make mistakes. But sometimes, these mistakes do not have an immediate effect and surface later on during the final rollout. 

But we can avoid this by combining the development with a suitable software testing methodology. Wait! Don’t be confused about the term; let us explain.

What is Software Testing Methodology?

Testing methodologies in Software Testing are nothing more than strategies designed to tackle one of the biggest problems in development; finding errors and fixing them. 

With every passing minute, the deck of technologies, coding languages, possible integrations, and more is growing in sheer number. We cannot expect to have only one set methodology for every other kind of development process. 

This is why software testing is divided into specific types, from which you get to choose and apply the most suitable one for your project.

Let’s learn a bit about the type of software testing methodologies.

Types of Software Testing Methodologies

In broader terms, the methodologies are divided into two types; Functional and Non-functional testing. 

But as we go deep into the subject, we’ll be introduced to existing methodologies belonging to these two types of testing. But before venturing into that, we’d have to understand the fundamental difference between functional and non-functional testing.

Read More: Types of Software Testing

Differences Between Functional and Non-Functional Software Testing Methodologies

We can go on giving you complex bookish definitions of functional and non-functional software testing methodologies, but we won’t do that. Instead, let’s give you an example of some sort and understand the real purpose of testing in software testing methodologies.

Now, suppose we have an application ready to be rolled out, and before presenting the final product to the client, we have to test it. So, at the very beginning, we try the application’s actual usage by distributing it among peers, who check if everything that is visually present works or not. Then we move on to the next step, where we check the actual productivity or performance of the application.

When we check out the application’s overall functionality, it’s called functional testing. But when we move towards checking the code and performance, it’s called non-functional testing.

It’s essential to test your application with both types of methodologies. You don’t want an application that looks good, but lags and breaks down in under a minute when put under pressure.

What are the Methods of Functional Testing?

Functional testing is neatly divided into four parts, which come after one another sequentially. The testing cycle starts from unit testing, where we test individual components to acceptance testing and ends at acceptance testing. 

There are several advantages that make functional testing a must for all software products. It helps to determine whether or not the product is on the right track. Early detections of errors help the developing team to find fixes before the product moves on to the next stage. However, functional testing can sometimes miss out on logical errors. Also writing test scripts often takes a significant amount of time and effort. 

Let’s get to know more about each method in greater detail.

Unit Testing

As the name suggests, unit testing is done in a manner where we go on testing individual components of the code. One single part of the code which can take only one input and produce a single output is tested at once. 

The advantage of unit testing is that it’s executed while we’re writing the code and helps to reduce the possibility of errors. It helps reduce bad code, but it also sets the code straight and makes it clean and ready to be documented. 

On the other hand, it takes more time to write sets of testing codes while already being in the middle of development. Moreover, it can only detect and solve issues related to logic and code; when it comes to UI, it fails to attest to that. 

It is the basic level of testing and mandatory to perform to make the further process easier. One of the best development practices is to develop the unit test code hand in hand rather than isolating it from any largely developed application code.

Integration Testing

It is not necessary that if all the individual components are working fine, their union will also act the same way. After testing individual members, we check if these components usually work. This kind of testing is called integration and is introduced after unit testing is performed. 

It is necessary if larger teams do development and the components of the whole system are divided into smaller parts. But it’s not an easy feat to perform integration testing as it is a time and resource-intensive process. 

If we do not perform integration testing, we’d be setting up for failure. It can cause severe problems during the assembly as we’d have to manually find and fix bugs in the system if the application breaks.

System Testing

We’re also almost done with the testing and development if we’re at the system testing phase. Here, we’ll have to compile the whole system and test if it gives the final output as described at the time of ideation of the application. 

One of the significant differences between system and integration testing is that, while doing the system testing, a tester need not be aware of the internal workings of all the modules. All they need to know and care about is the final output of the application. 

It is necessary to do system testing to find bugs and remove them before the final rollout. In this stage, we know if the system developed will work or not. The main advantage of system testing is that we can have it tested by a non-coder as well, as this level of testing does not require a need for coding knowledge. 

It’s costly both in terms of time and money and expenditure of additional resources such as long person-hours. For example, if a bug is found at this level, it will kickstart the development process from the very beginning.

Acceptance Testing

This is the absolute last step in the functional testing cycle. Here, we involve the end-user in the testing process. The testing is divided into two stages; Alpha testing and Beta testing. 

The users are involved in the beta testing phase and are called beta testers. They test the application through most situations or various use cases independently. 

Generally, it is done to generate public feedback, which tells them if the new application is ready for launch or not. So, if you’ve ever been a part of the beta testing, then the app you were generating user feedback for was in acceptance testing.

It is mandatory to get the final version of the application checked by the actual user. While it may be easier to perform, finding beta testers is tough to crack. Furthermore, beta testers have to be educated on the go concerning the app’s functionality to generate valuable feedback.

Acceptance testing is a key test because it lets the developer team learn about the user experience of the product. So if there are any quality issues, the team can solve them to improve the performance of the product. However, sometimes the acceptance test fails to provide valuable feedback as the users are not always willing to cooperate.

What Are The Methods Of Non-Functional Testing?

Once we’re through the functional testing, we have to optimise the application’s output. Nobody wants an application that looks aesthetically pleasing but, when you operate, produces heavy lag. 

The main advantage of non-functional testing is that it helps the team to analyse the product behaviour in terms of performance, security, load management and other parameters. This way the team is well equipped for things that could go wrong when it is used by the users in real-time.  

Non-functional testing, however, has a few disadvantages that make it expensive and time-consuming. The key con is that non-functional tests become irrelevant for updated software. So whenever the product is updated, new non-functional tests are needed to be performed on it. However, the test scripts from the earlier tests can be used without having to write code again. 

To check for performance, compatibility, and code-related issues, we use four non-functional testing methodologies, which are as follows.

Performance Testing

When an application is done and dusted and completed the entire cycle in the software development life cycle or SDLC, it needs to be tested for performance. 

Here, the application goes through intensive loads to a point where breakage starts to check the application’s full potential. Three significant tests are designed for performance testing: stress, load, and scalability.

With these three, you’d know if your application is beneficial to the end-user or is just a good looking piece of software. 

For almost every enterprise product we should major the benchmark for the application. Which is done by the performance team. This helps to understand whether the application crashed at a certain load. 

A considerable amount of money goes into testing, and various environments are needed for the test, which brings us to our next point, which is that it’s pretty costly. Still, it’s a necessary expense to bear. 

It has some flaws like performance testing needs to be done by someone who knows what they are doing. The load that the application is made subject to needs to be relevant and the test approach should also be accurate. Which can sometimes result in inaccurate and false results. On the brighter side though, performance testing helps to improve the load capacity and user experience. For every enterprise product, we should major the benchmark for the application. This is done by the performance team. This also helps to understand if an application crashed at a certain load.

Security Testing

Individuals or organisations with malicious intent can break down your application, steal data and personal information, and do more harm. To protect against all that, we perform security testing when the application is ready to be rolled out. 

The usual testing method includes penetration testing, where we deliberately try to hack the application in every possible way. This gives us a good idea of the leakage points to be sealed off.  

A lot of time, attackers try to send anomalies to hack or affect the application. The security team tries to catch such kind of bug/ issue before the product goes into production.  

It secures the application against potential threats and boosts the user’s confidence in its usage, which results in increased growth in the number of total downloads for the application. 

The testing phase usually involves sending some anomalies into the application as an attempt to hack or affect it (by the attacker) while the security team tries to catch the bugs that could possibly sabotage their code. This is done before the production phase.

But security testing bears high costs both in terms of time and money. Moreover, we need certified experts in penetration testing to get enriched results.

Usability Testing

What kind of an application would it be if it’s not user-friendly? This is where usability testing plays an important role. It checks the application’s user interface by having real users interact with it. So, to generate real-time data on what user’s like, what are the user’s pain points and related data.

While this looks like a necessary step, it has its downsides too. The data generated are from a limited number of people as the group size for the study is always concentrated. Moreover, the cost to impact the application ratio is relatively high. Due to this, this one step of testing is often skipped if we’re talking about small-time development.

Compatibility Testing

If your application is a perfect ten on ten when it functions as a standalone entity but starts to break when it has to collaborate with others, it’s of no use. We perform compatibility tests to check if the application is compatible with other operating systems, devices, hardware, and more. 

While performing compatibility tests, we can also add extra documentation for items or requirements needed for collaboration with other applications. Another advantage is that it helps to efficiently create education material and solve bugs that might be incurred. But on the other hand, it brings all the security issues involving a third party, which can negatively affect the system.

How To Decide The Best Software Testing Methodology For Your Next Project?

With everything that we have educated you till now, we assume that you already know the answer to that. But to clarify, we’d say that a mix of both methodologies should be in the mix. 

One of the significant factors in deciding the software testing methodology should be the application’s scalability. If you’re only going to use it among a local closed group, you don’t need that much testing, but if you’re planning to launch globally, the testing methodology should justify the cause.

Conclusion

Software testing is an integral part of the software production cycle. It helps us ensure that the software meets the expectations. Functional testing helps us to test the functioning of the software. Unit testing tells us whether or not the individual units work. Integration testing lets us know the functioning of all the individual units together. The system unit further confirms whether all the integrated units of the software work together as a whole. 

Whereas, non-functional testing helps to analyse the performance of the software. Performance testing is done from an end user’s perspective to check for the performance of the software under a certain amount of load. Compatibility testing makes sure that the software is compatible with various types of operating systems, hardware, etc. However,  an application or product will need to pass all these types of software testing and more, in order to confirm its functionality and be launched.

Additional Resources

• Software Testing MCQ
• Software Testing Interview Questions
• Principles of Software Testing
• Testing Tools
• Manual Testing Tools
• Automation Testing Tools
• API Testing Tools
• Performance Testing Tools
• Automation Testing Interview Questions
• Manual Testing Interview Questions & Answers
• Selenium Interview Questions
• Difference Between Testing and Debugging
• How To Become A QA Engineer?
• Test Plan vs Test Strategy
• Difference Between Alpha and Beta Testing
• Smoke vs Sanity Testing