Functional Testing

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Functional Testing in SDLC

In this article, I am going to discuss Functional Testing in SDLC. Please read our previous article where we discussed Use Case Testing Technique. At the end of this article, you will understand the following important pointers which are related to Functional Testing in SDLC.

1. What is Functional Testing?
2. What Does Functional Testing Accomplish?
3. How Should Functional Testing Be Conducted?
4. Functional Testing Process in SDLC
5. Types of Functional Testing Techniques in SDLC
6. Different Tools Used in Functional Testing
7. What are Functional Testing Best Practices?
8. What are the Advantages of Functional Testing?
9. What are the Disadvantages of Functional Testing?
10. Differences Between Functional Testing versus Non-Functional Testing

What is Functional Testing?

Fundamentally, functional testing is a type of testing that ensures each software application function operates in accordance with the need and specification. The application’s source code is not a concern of this testing. By supplying the proper test input, anticipating the output, and contrasting the actual output with the predicted output, each functionality of the software application is examined. The user interface, APIs, database, security, client or server application, and functionality of the Application Under Test are the main targets of this testing. Manual or automated functional testing is also an option. It is a sort of software testing that is employed to determine whether a software application’s functionality complies with the requirement definition. Each function is tested in functional testing by providing the input, calculating the output, and comparing the actual result to the anticipated value. To ensure that an application or system’s functionality works as we anticipate, functional testing is portrayed as black-box testing. It is done to make sure the application is working properly. Because it concentrates on application design rather than real code, functional testing is often known as “Black-Box Testing”. Instead of testing the system, the tester must just test the program.

What Does Functional Testing Accomplish?

Black box testing is the main component of functional testing, which can be carried out either manually or automatically. Functional testing’s objectives are to:

1. Test Each Application Function: During functional testing, each application function is tested by giving the proper input and comparing the output to the application’s functional requirements.
2. Test Primary Entry Function: Functional testing involves checking all of the application’s entry and departure points by testing each entry function.
3. Test Flow of the GUI Screen: The flow of the GUI screen is tested during functional testing to ensure that the user can easily navigate the application.

How Should Functional Testing Be Conducted?

Checking the functionality of the program under test is the aim of functional testing. It is focused on:

1. Basic Usability: Functional testing includes basic usability testing to see whether the user can freely and easily navigate around the screens.
2. Mainline Features: This entails testing the application’s key features and features.
3. Accessibility: This entails evaluating the system’s usability for the user.
4. Error Conditions: As part of functional testing, it’s important to determine whether the proper error messages are displayed when there are errors or not.

Functional Testing Process in SDLC

Functional testing involves the following actions:

1. Determine Test Input: This phase entails determining the functionality that requires testing. Testing the major functionalities, usability features, and error circumstances are some examples of this.
2. Calculate Anticipated Results: Create input data based on the function’s specifications, then use these specifications to determine the output.
3. Execute Test Cases: In this stage, the designed test cases are carried out, and the results are recorded.
4. Compare the Actual and Expected Output: In this stage, the amount of variance in the results is calculated by comparing the actual output produced after executing the test cases with the predicted output. This stage demonstrates whether the system is operating as intended or not.

Types of Functional Testing Techniques in SDLC

1. Unit Testing: Unit testing is a functional testing method in which the various components or modules of the application are tested individually. It guarantees that each module is operating properly.
2. Integration Testing: Integration testing exposes flaws in the interactions between the integrated units by testing the combined separate units as a group.
3. Smoke Testing: Smoke testing is a form of functional testing method that verifies that the application’s core features and functionality are operating as intended.
4. User Acceptance Testing: User acceptability testing is carried out by the client to confirm that the system complies with the specifications and operates as intended. Before the product is released, this is the last testing stage.
5. Interface Testing: A type of software testing technique called interface testing looks at how well two different software systems communicate with one another.
6. Usability Testing: Testing for usability determines how simple and user-friendly a software application is.
7. System Testing: System testing is a type of software testing that is done on the entire integrated system to determine whether the system complies with the necessary requirements.
8. Regression Testing: Regression testing is carried out to ensure that the application’s features and functionality won’t be impacted by code modifications. It focuses on whether or not each component is functioning properly.
9. Sanity Testing: Sanity testing is a subset of regression testing and is carried out to ensure that the implemented code changes are functioning as anticipated.
10. White Box Testing: White box testing is a sort of software testing that enables the tester to examine how the software system functions from the inside out. Analyzing the code, infrastructure, and system integrations with the external system are all part of this.
11. Black Box Testing: Black box testing is a sort of software testing in which the functionality of the software system is examined without taking a closer look at its internal operations or structural components.
12. Database Testing: Database testing examines the schema, tables, and other components of the database that is being tested.
13. Adhoc Testing: Adhoc testing is a type of software testing that doesn’t adhere to any documentation or test plans. It is often referred to as monkey testing or random testing.
14. Recovery Testing: Recovery testing is a sort of software testing that examines a program’s capacity to bounce back from errors such as computer crashes, hardware errors, and program errors.
15. Static Testing: Static testing is a type of software testing that examines software flaws without actually running the software application’s code.
16. Grey Box Testing: Black box and white box testing are both included in the category of software testing known as “grey box” testing.
17. Component Testing: Following unit testing, component testing also referred to as program testing or module testing is a sort of software testing. Because of this, each test object may be independently tested without requiring integration with other components.

Different Tools Used in Functional Testing

The tools for functional testing are listed below:

1. Selenium:

Developed with the goal of supporting browser automation, Selenium is an open-source umbrella project covering a variety of tools and libraries.

• Web browsers are automated using it.
• The tester can create test scripts using a single interface and a variety of programming languages, including Ruby, Java, NodeJS, etc.
• It offers a playback tool for functional test authoring across the majority of current web browsers.

2. QTP:

The QTP tool can now UFT is a technology created to carry out automatic functional testing without the requirement of routinely checking the system.

• It can be used to test client-server, desktop, and web applications.
• It has VB scripting as its foundation.
• It is a commonly employed automation tool in the testing sector.

3. JUnit:

JUnit is an open-source framework for unit testing Java programs. Java programmers use it to create and run automated test cases.

• It can be used to automate tests for web applications in conjunction with Selenium WebDriver.
• It provides several annotations for describing test procedures.
• To conduct testing, it has test runners.

4. SoapUI:

One of the best tools for SOAP and web service testing is SoapUI. Functional, regression, and load tests can be easily and quickly created and executed.

• The interface has a user-friendly graphical design.
• It offers a code-free testing environment where sophisticated test cases may be created and run using drag-and-drop functions.
• It enables dynamic analysis of how well the functional tests cover the SOAP and REST service contracts.

5. Cucumber:

Cucumber is an open-source, Ruby-based testing tool.

• The user experience is emphasized by this tool.
• Setup and execution are quick and simple.
• Because of the way the tests are written, this tool makes it simple to reuse code in tests.

What are Functional Testing Best Practices?

1. Automate: Functional testing can be tedious, time-consuming operations, therefore the more automation there is, the quicker flaws can be found and fixed, and the more time and money can be saved. Automating significant test cases helps increase test ROI even though it may not be practical to automate all test cases.
2. Dedicated Automation Team: An organized automation team Automation needs specific knowledge, effort, and time. It is thought to be ideal to assign automation jobs to people who can do them.
3. Create Tests Early: Since requirements are still being worked out, it is best to start developing test cases as soon as possible. Later in the project development cycle, test cases can always be modified.
4. Select the Proper Tests: When automating testing, it is crucial to select the proper test cases. It’s better not to automate some tests because they involve setup and configuration both before and during execution. Automate tests that must be run repeatedly and are vulnerable to human mistakes.
5. Prioritize: The application’s features cannot all be tested because testers have limited time and resources. To develop test cases, start with high-priority functions.
6. Frequently Test: Create a basic test automation bucket and a plan for executing this test bucket frequently.

What are the Advantages of Functional Testing?

• Functional testing guarantees the delivery of a high-quality, bug-free product.
• Customer satisfaction: It guarantees both that the customer’s needs are met and that all requirements are satisfied.
• Functional testing is concentrated on specifications as they relate to consumer usage.
• Application functionality is correctly working: This guarantees that the application performs as planned and in a proper manner.
• Enhances product quality: Functional testing assures the product’s security and safety and enhances product quality.

What are the Disadvantages of Functional Testing?

• Missed logical and critical errors: When running functional tests, it is possible that logical and critical errors will go unnoticed.
• Testing that is redundant: The likelihood of completing redundant testing is high.
• Incomplete requirements: It becomes challenging to conduct this testing if the requirement is not full.

Differences Between Functional Testing versus Non-Functional Testing in SDLC

Functional Testing	Non-Functional Testing
Functional testing examines how an application behaves and functions.	Non-functional tests an application’s behavior.
It is based on what the customer wants.	It is based on what the client expects.
The goal is to confirm software actions.	The goal is to improve the software system’s performance.
The functional specification is used to conduct functional testing.	The performance standards are used to conduct non-functional testing.
It explains what the product accomplishes.	It explains how the product functions.

In the next article, I am going to discuss Non-Functional Testing in SDLC. Here, in this article, I try to explain Functional Testing in SDLC. I hope you enjoy this Functional Testing in SDLC article.