What is Automated Functional Testing: Types, Benefits & Tools
By Antra Verma, Community Contributor - May 25, 2022
Software testing evaluates the functionality of an application to find any bugs. It basically checks whether the developed application meets the specified requirements or not and identifies any defect in the software.
Software testing is mainly classified into two categories:
- Functional Testing
- Non-functional Testing
This article is focused on automated functional testing, its advantages, various types, different techniques, and steps involved in performing functional testing.
What is Functional Testing?
Functional testing is a type of testing that verifies if each function of software operates according to the specified requirements. This type of testing only involves black box testing and is not concerned about the source code of the application. Each functionality of a software application is tested by providing a different set of data inputs verifying the resulting output is as expected by comparing the actual results with the expected results.
Automated functional testing is a technique that executes test cases automatically using some specific code. There are various tools that allow automated functional testing which will be discussed later in this article.
Difference between Functional Testing and Non-Functional Testing
Functional testing allows testing the functional requirements of software while non-functional testing verifies the behavior of an application.
The main differences between functional testing and non-functional testing are given below:
|Functional Testing||Non-functional testing|
|Focuses on the user requirements.||Focuses on the user’s expectations.|
|Used for black-box testing.||Used for white box testing.|
|Describes what the product does.||Describes how the product works.|
|Executed before non-functional testing.||Executed after functional testing.|
Functional testing ensures that when a user receives a new message in the app, a notification is sent to the user.
Non-functional testing ensures that the notification is sent in as little time as possible.
Advantages of Functional Testing
The advantages of Functional Testing are as follows:
- End-user satisfaction: Functional testing ensures that a given product meets the actual requirements and the end-user will be satisfied with the product.
- High-quality product: It ensures the high quality of the product by replicating the actual product and testing it against the actual requirements.
- Bug-free product: It also ensures that the product has no bugs and is working as per the customers’ requirements.
- Better Security: Functional testing also checks for different security aspects of the software. It ensures the product is risk-free and can be used for storing users’ sensitive data.
Different Types of Functional Testing
Some of the different types of functional testing are discussed below:
Unit testing checks that each of the smallest components that can function independently operates as expected. In unit testing, developers test the code of each of these Units and identify any errors in the code. This helps in identifying possible bugs right at the beginning of a test cycle, saving time and resources. Each unit of code is thoroughly tested alone before moving to another unit.
Read More: Best Practices for Unit Testing
Sanity testing is done to ensure that all the major and vital functionalities of the application or system are working correctly. Sanity test is generally done after a smoke test.
Smoke testing is performed after each build is released to test the build’s stability. It is also called build verification testing.
Regression testing ensures that the addition of new code enhancements and bug fixing will not break the existing functionality or cause any instability and the application will work according to the required specifications. Regression tests are run for each release to check the effect of a new feature on existing functions.
Read More: How to run Regression Testing in Agile Teams
When the system is build-up of multiple functional modules, it is essential to check how they work coherently. It is because sometimes they might individually work perfectly but when grouped together to achieve an end-to-end scenario it might not deliver as expected. Validation of such scenarios is known as Integration testing. By performing end-to-end testing of the application, you can test how well the modules integrate with each other.
Read More: How to perform End to End Testing in Angular
Different Tools used for Automating Functional Testing
- Selenium is one of the most popular open-source automated testing suites for web applications. Selenium is composed of several components with each performing a specific role in aiding the test automation. Selenium supports multiple test system environments such as Windows, Mac, Linux, and browsers such as Chrome, Firefox, IE, etc.
- Puppeteer is an open-source node js library used for automating and streamlining the frontend development and testing respectively. Puppeteer contains APIs to interact and manage the Chrome browser in headless mode. However, it can also be used for non-headless execution on browsers like Chrome, Firefox, etc.
- WebdriverIO is an automation framework built to automate modern web and mobile applications. It simplifies the interaction with the app and provides a set of plugins that help to create a scalable, robust, and stable test suite. WebdriverIO leverages the power of the WebDriver protocol that is developed and supported by all browsers and guarantees a true cross-browser testing experience.
- NightwatchJS is an integrated, easy-to-use end-to-end testing solution for web applications written in NodeJS. It provides a built-in command-line test runner which runs the tests either sequentially or in parallel, with retries and implicit waits. It also works with BrowserStack out of the box.
How to perform Automated Functional Testing?
The steps involved in automated functional testing are given below:
- Determine Functionality: The first of functional testing is to determine the functionality of the product that needs to be tested and it includes testing the main functionalities, error conditions, and messages.
- Create Input Data: Next step is to create the input data for the functionality to be tested as per the requirements specification.
- Determine Output: After creating the input data, the output is determined for the functionality under test.
- Execute test cases: After determining the required output, the prepared test cases are executed.
- Compare Outputs: Finally, the output obtained after executing the test case and the expected output are compared to find whether the functionality is working as expected or not.
Best Practices for Automated Functional Testing
- Use well-planned test case execution: Test execution is the process of testing specific workflows in the app. It is crucial to functional testing. By planning test-case execution rigorously, one can ensure that the test case covers all the functionality.
- Write reusable test cases: Test cases should be written in such a way that they can be reused. It helps to save time and can reduce complexity.
Read More: Fundamentals of Writing Good Test Cases
- Embrace automation: While all tests cannot be automated, there will certainly be some opportunities, which can make it easier to run tests more often and save time in the software development process.
- Document everything: It is a critical aspect of testing. Documenting helps while working in a team as it makes it easier for other teammates to understand what bugs have been identified and how to fix them.
Read More: Benefits of Automation Testing
While Functional testing is the backbone of the testing process in the software development life cycle, it is essential to maintain a high level of accuracy for the tests. This is possible with the use of Real Device Cloud as opposed to Emulators and Simulators so that you can test your application under real user conditions. It allows you to identify the bottlenecks in the user experience by considering various real factors like network conditions, geolocation, etc. for a more realistic testing experience.
Teams can leverage cloud-based platforms like BrowserStack that offer a Cloud Selenium Grid of 3000+ real browsers and devices. It empowers teams to run concurrent manual and automated functional tests on desired real device-browser combinations online, using frameworks such as Selenium, Cypress, Playwright, Puppeteer, NightwatchJS, Protractor, etc. You can also integrate these functional tests with their CI/CD pipelines such as Jenkins, CircleCI, Travis CI, etc for streamlined software development using DevOps.
It also helps accelerate testing time with parallel testing, and get results faster without compromising on accuracy.