Functional Testing: What Is It? Meaning, Kinds, & Illustrations
Functional testing is frequently in mind when people use the word “testing” in a general sense. It’s about ensuring that the essential operations are carried out as intended. Functional testing includes so many different kinds of testing because its reach is so wide.
We’ll go deeply into the idea of functional testing in this post, along with its advantages, disadvantages, and recommended methods.
Functional Testing: What Is It?
Software testers that specialize in functional testing examine if an application’s features are operating in accordance with its requirements and functioning as intended. The stakeholders (development team or product owner) or the users themselves supply these requirements.
The main objective of functional testing is to verify that the program does its assigned tasks; it usually does not focus on the internal workings of the code or implementation specifics. It is among the most widely used and fundamental kinds of examination.
Functional Testing Examples
Let’s say you are testing an online application that needs users to register. Here, functional testing is merely performed to verify that the login page functions as intended.
So what things can one “expect” from a login page? A few that sprang to mind are:
User authentication, password reset, remember me, account recovery, and lockout
Authentication using many factors, particularly crucial in high-risk scenarios
Session management (make sure that, for security reasons, users automatically log out after a certain amount of inactivity)
User Observation
In order to direct the functional testing endeavor, those requirements have been decided upon and thoroughly documented. Functional testing for the Login feature usually has to be done more when security is prioritized. The following are a few instances of useful test cases found on the login page:
Verify if users are able to log in successfully using their correct login information, such as a registered username or email and password.
Test that users see an error message when attempting to log in with improper credentials (e.g., incorrect password or non-existent username).
Verify that the user’s account gets locked and they are unable to log in after a predetermined amount of unsuccessful tries to log in.
Test the password reset capability by initiating a password reset request through the “Forgot Password” link.
To make sure the user stays logged in during browser sessions, test the “Remember Me” option.
Verify that the MFA method (such as an SMS code or app-based token) is operational and test the MFA implementation by signing in with legitimate credentials.
Important Distinctions Between Non-Functional and Functional Testing
Functional testing is a necessary component of the test plan, but it shouldn’t be the only kind of testing your team does. Its counterpart, non-functional testing, is critically important.
1. What is testing that isn’t functional?
Software testing that concentrates on assessing non-functional aspects including system performance, stability, and dependability is known as non-functional testing.
In functional testing, testers attempt to provide a response to the query. Is the system able to perform its intended function?
In non-functional testing, testers attempt to provide an answer to the query. Can the system perform its intended function sufficiently well?
Here are five non-functional test scenarios to help you grasp the idea:
Calculate the system’s reaction time with a typical load.
In order to assess the system’s performance under high load and look for breakdowns or degradation in response time, simulate multiple user connections.
To get input on navigation, intuitiveness, and the entire user experience, test usability with real users.
To evaluate the system’s capacity to manage a higher workload, progressively add more work while monitoring performance indicators such as CPU and memory utilization.
To make sure users can only access the functions and data they are permitted for, test user roles and permissions.
2. How does functional testing differ from non-functional testing?
The main goal of functional testing is to determine if the system produced the intended results.
The “hows” of the AUT’s features, performance, security, scalability, etc. are validated through non-functional testing.
This is a brief table of comparisons for you:
|
Aspect |
Functional Testing |
Non-Functional Testing |
|
Purpose |
To verify if the software functions as intended and meets functional requirements. |
To evaluate non-functional attributes like performance, security, usability, and more. |
|
Focus |
Tests what the software should do. |
Tests how well the software performs certain functions or behaves under specific conditions. |
|
Scope |
Typically focuses on specific features or functionalities. |
Covers a broader range of attributes beyond functionality. |
|
Examples of Testing Types |
Unit Testing, Integration Testing, System Testing, User Acceptance Testing. |
Performance Testing, Security Testing, Usability Testing, Compatibility Testing. |
|
Test Criteria |
Pass/fail criteria are often straightforward based on expected outcomes. |
Pass/fail criteria may involve thresholds or benchmarks (e.g., response time should be below 2 seconds). |
|
User Focus |
Ensures that the software meets user needs and expectations in terms of features. |
Ensures that the software meets user needs and expectations in terms of performance, security, usability, etc. |
|
Objective Measurement |
Often involves binary outcomes (pass/fail) based on expected behavior. |
Often involves quantitative measurements and benchmarks for non-functional attributes. |
|
Tools and Technologies |
Functional testing tools may include Selenium, JUnit, TestNG, etc. |
Non-functional testing tools may include JMeter, OWASP ZAP, LoadRunner, etc. |
Types of Functional Testing
- Unit Testing: Developers carry out unit testing by writing scripts to check if the various parts or units of an application adhere to the specifications. Writing tests that invoke each unit’s methods and validate them when they return values compliant with the requirements is typically required for this.
Unit testing requires code coverage. Make sure the following are covered by test cases:
Line coverage
Code path coverage
Method coverage
- Smoke Testing: After every build is released, smoke testing is carried out to make sure that the program is stable and free of abnormalities.
Sanity testing: Usually carried out following smoke testing, this checks that all of an application’s primary features operate flawlessly both on their own and in concert with other components.
Regression Testing: Regression testing verifies that modifications to the codebase (new code, debugging techniques, etc.) don’t interfere with or cause instability in the functions that are currently in place.
Integration Testing: Integration testing is done to make sure that individual modules function as intended when used in combination with one another when a system needs numerous functional modules to function properly. It confirms that the system’s final result satisfies these prerequisites from beginning to end.
- Beta/Usability Testing: During the beta/usability testing phase, real users test the product in an operational setting. This phase is essential for determining the degree of a customer’s comfort with the interface. Their input is gathered in order to make additional code enhancements.
In summary
Any software testing mechanism must include functional testing. It ensures that a system performs in real time and precisely as intended. Functional testing leads in the delivery of a high-quality solution that satisfies customer needs and offers extremely gratifying user experiences since it is conducted from the standpoint of the user. Naturally, both corporate staff and developers will find this to be more convenient. Be a master of this skill by opting for software testing training in Noida, Delhi, Gurgaon, Kanpur, Pune and other Indian cities.
