Building a strong functional testing plan, why is it critical?

Functional Testing

The success of any software application is underpinned on its acceptance by the users. This can only happen when the software application provides the best user experience. The users find a software worthy of acceptance when its features and functionalities work as per the pre-defined specifications. To ensure the same, various components of the software suite should undergo rigorous functional testing. In any quality assurance process, the software in the build phase and thereafter should be validated for quality. Here, the software components (individually and collectively) need to be tested to check if the actual output is on the expected lines. 

The software functional testing process ensures the actual output of specific components does not impact the other components. The testing process should verify and validate the software application interface to address user requirements. Importantly, the testers should see to it that all boundary case scenarios and their impact are studied, and suitable inferences drawn.

How critical is functional testing?

In an increasingly digitized world where the functioning of critical processes is dependent on the quality of software, testing the software components is not just important but extremely critical as well. Let us understand this better with two examples.

·         In the healthcare sector, most advanced diagnostic systems are run by embedded software. Here, any glitch in the functioning of such embedded software can lead to the system giving erroneous readings. These readings can, in turn, lead to the wrong diagnosis of an ailment. Consequently, the physician, based on the readings, can administer a dosage of medicine or treatment protocol that is detrimental to the health of the patient.

·         In the IoT-based environment, should the components of the embedded systems do not function to their optimum, the quality of the IoT environment can suffer.

Building and executing a strong functional testing exercise

Since testing the components of software is critical to obtain a seamless user interface, it should be done in accordance with a robust plan. The testing methodology is given as under:

·         Define the test data and set up the criteria to identify positive or negative testing.

·         Conduct impact analysis to study the behaviour of each and every component and their impact on other components.

·         Create functional test cases and determine the use of specific test data.

·         Execute functional test automation using tools like OpenSTA, WinRunner, Load Runner, Rational Suite, and Mercury Interactive’s QTP etc.

·         Perform regression testing.

·         Review test requirements and prioritize the conduct of tests.

·         Document and analyze the error reports.

·         Leverage dashboard data for the management view.

When should a functional test be conducted?

Since testing the components of an application determines if they function appropriately for the users, a functional test should form the core of any Quality Assurance exercise. The basic functional tests should be conducted early in the development stage while the core activities should be performed throughout the SDLC. For example, while developing a mobile application, each feature of the app such as login, push notifications, and payment gateways (if present) should be tested.

Primary techniques comprising a functional test

Black box testing: Here, the functional and regression tests are executed using the user interface. The testers do not have any idea about the design, implementation or structure of the item to be tested. The typical techniques include boundary value analysis, cause-effect graphing technique, equivalence class partitioning etc. It is mainly an external test that is applicable to the higher test levels such as user acceptance testing and system testing. The test focuses on checking the type of functionality being performed by the software.

White box testing: Here, testers or developers focus on the code to identify bugs or errors. The testers are aware of the internal structure and require programming knowledge. This type of testing is applicable to the lower level of testing such as integration testing, unit testing etc. The focus of the testers is on verifying how the system is performing.

Conclusion

Comprising types such as unit testing, regression testing, system integration testing, smoke testing, sanity testing, and user acceptance testing, the software functional testing process should ensure a software application performs as per the specifications and meets the user requirements.

Diya works for Cigniti Technologies, which is the world’s first Independent Software Testing Company to be appraised at CMMI-SVC v1.3, Maturity Level 5, and is also ISO 9001:2015 & ISO 27001:2013 certified.