Functional testing

It’s important for businesses that functional testing is done right to get the desired outcome. So, in this post, we’ll dive deeper into what functional testing is and how it works. Then, we’ll discuss the benefits, challenges, and solutions that come with it.

Functional testing is a type of software testing that focuses on the functionality of an application.

What is functional testing?

Functional testing is a type of software testing that focuses on the functionality of an application. It ensures that the software functions according to the requirements. In functional tests, testers identify what an application is supposed to do and run a series of tests to make sure that it performs as expected. This involves testing individual features, user interfaces, and system interactions.

Let’s take an example of an e-commerce platform. One of the functions of the applications is to allow users to add items to a cart, proceed to checkout, and complete a purchase. If a tester is testing this function, they’ll check the following:

• The user can add and remove items from the cart correctly.
• The checkout process proceeds smoothly without errors.
• Payment gateway functions are integrated securely and are responsive.
• The system sends order confirmation emails to users post-purchase.

The ultimate objective of functional testing is to ensure that a piece of software meets the customer’s specific functional requirements. It also ensures that users don’t encounter feature issues or bugs while using the application.

Nonfunctional testing

In addition to functional testing, quality assurance (QA) teams will perform non-functional tests designed to review and verify other aspects of a software application. Non-functional testing may evaluate usability, reliability, scalability, compliance, performance under different loads, and other criteria that are not directly related to business function.

Where functional testing is intended to ensure that software meets the requirements of an organization, non-functional software testing is designed to ensure that software meets the expectation of users. Most non-functional tests are automated.

Nonfunctional software testing is designed to ensure that software meets the expectations of users.

What is the relationship between functional testing and manual testing?

Functional testing and manual testing are related, but they represent different aspects of the software testing process. The former focuses on what to test, while the latter focuses on how to test.

Functional testing verifies that specific functions within an application work according to specified requirements. It involves testing individual features to ensure that the application meets functional expectations.

Manual testing, on the other hand, refers to the way testers test the application. In manual testing, testers manually perform test cases without using automation tools. This helps in exploratory testing and identifying visual issues. Manual testing is preferred when test scenarios are complex, infrequent, or require human judgment.

Manual testing is one of the ways to perform functional testing.

Types of functional testing

The most common types of functional tests include the following:

• Unit tests evaluate each individual unit and module code to make sure they perform appropriately.
• Component tests validate objects or parts of the software separately.
• Smoke tests, which are a type of regression test, evaluate software in a noncomprehensive manner to ensure the software works well enough (or isn’t riddled with too many issues) to move on to additional tests. A smoke test is also known as a build verification test.
• Integration tests examine multiple individual units of the software as a group to make sure they interact appropriately.
• Regression tests ensure that code changes have not had a negative effect on the functionality of the software.
• Sanity tests, which are a type of regression test, evaluate the software in a noncomprehensive manner after code changes have been made to ensure the changes didn’t create any serious issues. They’re typically performed after smoke tests.
• System tests ensure that all system elements work as intended. They also verify system performance and functionality and are typically performed by testers who have not played a role in developing the program.
• User acceptance tests make sure the software meets user needs. Often the last step before software goes live, these tests are usually performed by end users and measure how well the application performs in typical scenarios

How does functional testing work?

Functional testing requires proper planning and understanding of the application and what the users would use it for.

First, you begin with a thorough understanding of the functional requirements. You can usually find this information in specifications, user stories, or acceptance criteria during the design and development phase. This helps you identify the functions to test and define outcomes to expect.

Next, you create test cases to test different functions of the application. Test cases should include both positive and negative scenarios. Once the test cases are ready, choose the tools to use for testing and set up a testing environment that closely resembles the production environment.

Now, it’s time to start functional testing. The steps involved in functional testing typically include:

1. Using test data to identify inputs
2. Identifying the expected outcome for different test cases
3. Running test cases with inputs
4. Comparing the expected results to actual results

During functional testing, you should properly document the results. If you identify any functional bugs, create detailed documentation mentioning how you found the bug, the steps you followed, and the input you provided that led to the bug, including screenshots and screen recordings if necessary. The next step is to pass this information on to the development team so that they can fix the issues. Once that’s done, you should retest the functions to make sure they’re working and repeat the above process until the application is at an acceptable state.

There are several methods and QA testing tools that you may employ to execute tests and gather data.

Functional testing techniques

Regardless of what type of functional test is performed, there are several methods and QA testing tools that may be employed to execute tests and gather data.

• Manual scripted testing is typically used when very complex tests must be run, when adhering to strict regulations that require documentation, and when testing legacy systems doesn’t easily support automated tests.
• Exploratory testing is a form of manual testing where testers set out to understand how the software works and then identify different tests to run based on that understanding. Since exploratory testing is not scripted, it typically mirrors how users will interact with the software in actual practice.
• Automated testing can be used in a variety of scenarios to run tests more quickly and improve the accuracy of results.
• Behavior-driven development (BDD) testing is a method that encourages collaboration between testers, developers, product owners, and others to create a shared understanding about requirements. BDD testing is focused on users and delivers high levels of efficiency and effectiveness in user experience testing.
• Risk-based testing prioritizes tests for high-risk areas of software and mitigates risk by ensuring a high level of test coverage. Risk-based testing is often used to focus testing resources efficiently.

Benefits of functional testing

Functional testing is important to ensure that the software is performing as expected to deliver value to both users and businesses. It helps detect and fix issues early, improving user experience and enhancing the overall software reliability. Let’s look into some of the major benefits of functional testing.

Better software quality

Functional testing improves software quality because you test the application thoroughly and validate each feature and functionality according to requirements. This minimizes bugs, reduces unexpected behaviors, and ensures the software meets user and business requirements.

Better user experience

Functional testing focuses on testing the application from an end user perspective. It uses real-world scenarios to verify that the software behaves as expected when users interact with it. This context helps in identifying and fixing issues, which is critical to enhance user experience.

Cost savings

Detecting and fixing bugs during the early phases of development and testing is cheaper than addressing them post-release. Functional testing allows you to identify flaws before they become a major issue—especially if it has high dependency. Fixing them earlier reduces the risk of costly, time-consuming bug fixes later.

Reliability

Functional testing tests and verifies each function of the application multiple times. This makes the application more predictable and stable, reducing system failures. This improves high uptime, resilience, and, therefore, reliability.

By automating functional testing, you can run test scripts repeatedly and consistently across different environments.

Automated functional tests

By automating functional testing, you can run test scripts repeatedly and consistently across different environments. Automated functional testing allows testers to execute a large number of test cases in less time, making it ideal for regression testing and frequent releases. Testers can identify bugs faster and with less human effort. Automated functional testing also supports continuous integration and continuous deployment (CI/CD) pipelines.

Challenges of functional testing

Managing functional testing can be extraordinarily complex, especially in an environment with multiple technologies. The challenges of conducting functional tests include:

• Gathering clearly defined and complete requirements for each piece of software
• Planning tests by identifying potential functional gaps
• Developing a test strategy to complete tests within given deadlines, using appropriate resources, and ensuring optimum test coverage
• Executing tests and ensuring that test plans accurately match the functionality to be measured
• Managing defects uncovered by tests
• Ensuring that reporting on defects is complete, clear, and consistent, and that severity and priority is accurately attributed
• Reporting results of functional tests within a certain timeframe and in ways that make sense to each stakeholder
• Gathering metrics to gauge the effectiveness and quality of the testing process

Solutions for automating functional testing

Tricentis Tosca simplifies functional testing by overcoming the barriers of legacy and conventional functional test automation methods. With innovative risk-based and model-based test automation approaches, Tricentis Tosca simplifies end-to-end regression testing for more than 160 technologies.

Tricentis Tosca provides Agile software testing teams and DevOps with:

• Support for multiple testing methods: Use exploratory testing, manual testing, automated testing, and BI/data warehouse testing to test functional requirements
• Control over the test suite: Plan tests, design test cases, manage and maintain test data, and gain insight into business risk
• Sustainable test automation: Minimize test maintenance and maximize reuse so that rapid change won’t disrupt test automation
• An easy-to-use interface: Create test cases by scanning, recognizing controls, or recording – all while still being business readable
• Best-of-breed technology: Plug into continuous integration frameworks, use distributed execution, simulate missing systems, leverage APIs, connect with other tools, and provide advanced reporting and analytics
• Integration with enterprise environments: Test cross browser, mobile, SAP and SAP Fiori, Java, .net, XML, JSON, REST, ServiceNow, and more
• Tests aligned with business risks: Understand what tests and data are required to cover business risk. Change the focus of testing from “pass/fail” status to “Is the level of business risk in this software acceptable?”