Automated Functional Testing: A Complete Introductory Guide

Today’s post is going to be all about automated functional testing. What’s this category of tests really about? Why do…

Automated Functional Testing
By Testim,

Today’s post is going to be all about automated functional testing. What’s this category of tests really about? Why do you need it? How do you go about implementing it? What are the challenges you might face when doing so? With this post, we’re going to answer these questions—and more.

We’ll start out by defining functional testing. Then, we’ll go on to explain the benefits of functional testing so you understand why you need it, even if you already employ other types of tests. After that, we’ll reach the “automated” part of “automated functional testing.” We’ll define automation, explaining how it’s imperative to apply it to testing. Then, we’ll be ready to cover automated functional testing.

With the definitions out of the way, it’s time to get to more specific advice. You’ll see how to get started with automated functional testing, the possible challenges on your journey, and how you can beat them.

Functional Testing: What It Is and Why You Need It

Functional testing, as its name implies, concerns itself with how a given application functions. Does the application meet its functional requirements? Does it solve the problems of its users? These are the kind of questions that should be answered by functional test cases.

Functional testing is, then, a type of black-box testing. In other words, functional testing couldn’t care less whether you’ve used an array or a list to model a given concept. The only thing that matters is that the application’s external behavior meets the requirements.

Unit Tests Are Not Enough

In some software development cycles, there are people who seem to think of unit tests as the ultimate software panacea, the mythical silver bullet that will solve all software crises for good.

There’s no such thing, of course.

Make no mistake: unit tests are awesome. They can either lead to a cleaner, low-coupled design or—in the worst scenario—make you acutely aware of poorly designed, high-coupled code. They often cause developers to learn about good development practices, such as immutability, purity of functions, and separation between logic and presentation. More importantly than all of that, a comprehensive suite of unit tests empower developers to fearlessly refactor, knowing they have a safety net if they break something.

Did you notice who is missing from the previous paragraph? The user.

Let’s Think of the Final Users

The previous section covered some of the benefits of unit testing. You’ll notice, though, that those benefits seem to benefit mainly the developers themselves. Sure, cleaner code and a more maintainable application will indirectly benefit users, no doubt about that. But that’s not enough.

There’s a school of thought that argues that “unit testing” is an unfortunate name for an otherwise great tool, and I agree with that. I’ve seen people use “executable specifications” as an alternative name. The point is this: unit tests aren’t really tests. They’re verifications that developers use in order to check that the code they wrote does what they think it does.

But who’s checking whether the code they wrote does what the user expects it to do? That’s the job of functional testing.

It is possible to write a correct, elegant and efficient solution…to the wrong problem. While unit tests will make you confident you’re solving the problem correctly, functional testing is what ensures that you solve the right problem, for the right users.

Automated Functional Testing: Understanding Its Benefits

Up until now, you’ve seen what functional testing is and why you need it, even if you already use other, also very useful, types of tests. Now it’s finally time to add “automation” into the mix. We’re going to define automation and show why its use is imperative in testing. We’ll then zoom in and talk specifically about automating functional tests.

Automation Is Great. Are We Using It?

As developers—and software development professionals in general—we can consider that automation is the whole raison d’être of our jobs.  Why shouldn’t we use it to improve the efficiency of the software development process itself?

Sure, programmers have been automating aspects of their job since the dawn of software engineering. But in recent years, the industry’s use of automation increased to unprecedented scales. We can see this reflected in the growing use of automated testing and, more generally, in the DevOps movement.

Automation in Testing Is a Must

If there’s one area in the whole software development process that really benefits from automation, that area is testing. That’s due to one of the most unique characteristics of software—even the smallest change in one area of an application can cause unforeseen consequences in a totally different area. Yep, that’s a serious problem. In an ideal application, with sound architecture, something like that should never happen. We don’t live in the ideal world, unfortunately, and things like that do happen frequently.

The implication of this unique software characteristic is crucial. After making some change on a codebase, the only way to be sure the whole application still works properly is to retest the entire app. Just testing your own change isn’t enough. You could’ve broken something and you’d never know.

That means that, in modern software development, applying automation to testing is imperative.

Automated Functional Testing: You Can Have Your Cake and Eat It Too

Automated functional testing is, in a way, the best of both worlds—it brings to the table the benefits that automation provides to all kinds of tests, along with the functional testing ethos of putting the user’s needs first. It takes automated testing to its full potential, making it not only a tool for developer confidence (which is already awesome in itself), but also a tool for customer satisfaction. It bridges the gap between QA professionals and developers, creating a shared space where they can collaborate.

Automated functional testing sounds awesome—and it is—but how do you actually get started with it? I’m glad you asked.

The first step is to have specs. You can’t have tests that verify whether the application conforms to the specifications if there aren’t any. For this first moment, it shouldn’t matter that much whether the specifications are embedded into the code or recorded in an external document. The important thing is that you have them.

Then, it’s time to start thinking about the possible test cases for your application. Start your app, go to its main screen, and look at it critically. What are the tasks the user is supposed to perform here? How could they go wrong? It’s even better if you don’t do this on your own. Instead, bring in some coworkers to help. Do a brainstorm session on the current screen. Write down all of the ideas that you can come up with.

Then do the same with other areas of the application.

After all of this, do you have a reasonably sized list of possible use cases? Great, now it’s time to go shopping for tools. This post is meant to be platform agnostic, so we won’t actually recommend particular testing frameworks. But it doesn’t matter your language or tech stack of choice, rest assured, there are automated functional testing tools out there for you.

Automated Functional Testing Challenges: What They Are and How To Overcome Them

As promised, now it’s finally time to cover some of the common challenges when implementing automated functional testing. What are those? How do you beat them? Keep reading to learn more.

QA Skepticism

One of the most common challenges when implementing all kinds of automated testing is skepticism. It’s 2019 and there are still many professionals that are unfamiliar with automated testing, believe it or not. There are also others who know about automated testing but don’t quite buy into the usefulness. How do you deal with the skeptics? Education.

You must use every kind of material at your disposal—books, online courses, on-site training, and what have you. After some training, make your QA people get their hands dirty. Have them start creating automated functional tests, first on a very small scale. Then, start to gradually increase said scale. In true Agile fashion, use small steps, reviewing your results in short iterations. Rinse and repeat. That’s pretty much it.

Developers Skepticism

When it comes to developers, it’s possible that some of them have jumped on the “unit testing = software panacea” bandwagon. If that’s the case, make them get off the bandwagon. The tool for doing so? You guessed it, education. Hands-on education.

Have your developers collaborate with QA people. Create small, cross-functional teams on which QA and developers can work side by side. As automation experts, developers might be of incredible help, mentoring QA people on the nuances of automated testing frameworks and tools.

This approach will create trust and empathy between developers and QA professionals, bridging an otherwise insurmountable gap, and destroying every trace of skepticism toward automated functional testing on both sides.

Maintenance Burden

Another challenge of automated functional testing—and other types of automated testing—is the maintenance burden. You see, test code is code, after all. It can contain bugs. It might be unreadable. And the list goes on.

How do you overcome this challenge? First of all, education again. Educate yourself and your coworkers on the best practices for writing tests, be them functional or otherwise. Read about ways to keep your test code clean and readable. Learn about the common mistakes people make when writing tests and what you should do to avoid them.

Finally, there are tools that can ease your burden by providing you with test management capabilities that you would otherwise not have, such as comparing versions of the same test, scheduling tests executions, and automating bug reporting.

Automated Functional Testing Helps You Solve the Right Problems at the Right Speed

Software development is a field that evolves at breakneck speed. In order to keep up with such rapid change, companies rely more and more on automation, giving birth to approaches such as DevOps and continuous delivery.

Automated testing plays a crucial role in this scenario. It’s unfeasible for teams to completely retest their application by hand each time someone has made a change. Automated testing is way past the point of being something that’s “nice to have”—software development in the 21st century requires it.

Automated functional testing, in particular, brings the benefits of automation to a type of test that puts the user front and center. It bridges the gap between QA and developers, ensures the application meets the user’s needs, and takes automated testing to its full potential.

Author bio: This post was written by Carlos Schults. Carlos is a .NET software developer with experience in both desktop and web development, and he’s now trying his hand at mobile. He has a passion for writing clean and concise code, and he’s interested in practices that help you improve app health, such as code review, automated testing, and continuous build.