White Box Testing with Real Life Example

White-box testing techniques analyze internal structures, data structures used, internal design, code structure, and software behavior. This article includes white box testing with real life scenarios based examples. It also includes its different types

White box testing is when a person uses an actual device to perform testing. This allows for much more accurate results since discrepancies in the device’s features or an operating system won’t affect test outcomes. It is typically more time-consuming than grey box testing since developers need to access actual devices to perform testing. However, it’s much more effective since it detects bugs earlier in the development process than gray box testing. Additionally, this techniques help developers identify and fix bugs in their programs before releasing them to end users.

Table of contents

• What is White box testing?
• Advantages of White box testing
• Disadvantages of White box testing
• Testing Techniques and Code Coverage
• Types of White box testing
• White Box Testing Tools
• Conclusion

What is White box testing?

White-box testing (also known as clear-box testing, glass-box testing, transparent-box testing, and structural testing) tests the internal structure or behavior of an application instead of its functionality (that is, black-box testing). Software testing methodology). White-box testing uses an internal view of the system to design test cases. Testers choose inputs to practice code paths and determine expected outputs. White-box testing can be applied at the software testing process’s unit, integration, and system levels.

Real life scenario

1. Suppose there is a registration page in an e-commerce website to be tested. If we are doing black box testing, it will only be checked whether the registration page is working fine or not. But in the case of white box testing, all the functions or classes(which are called) will be checked when that registration page is executed.
2. If you are using a calculator, then in the case of black box testing, you will be concerned if the output you are getting is correct or not. But in the case of white box testing, testers will check the internal working of the calculator and how this output was calculated.

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Advantages of White box testing

1.Identify issues

Before any coding or creation is completed, white box testers perform manual assessments of web applications, mobile apps, and other software. This allows developers to identify issues with their programs before they build them and refine their designs based on test results.

2. Provides insights

It can be used to prove a concept or an idea for a product before creating it. It can also provide insights into how changes to a product’s design affect its functionality before any work is done. For these reasons, white box testing has become an essential part of software development as more people recognize its value.

3. Feedback

White box testing is ideal for gathering feedback on a particular feature before any coding has taken place. This allows developers, testers, and project managers to react appropriately and fix issues users have pointed out early in the development process.

4. Catch bugs

It can help catch bugs early in the development cycle and validate new design concepts or ideas for products before implementing them. It’s also useful during normal development when coders are fine-tuning their programs and reacting to feedback from end users.

Disadvantages of White box testing

1. White box tests are written to test specific implementation details. This means that the tests are tightly coupled to the implementation, so if the implementation changes, the tests will fail. So when the implementation changes, you have to do some extra work to update the tests to match the implementation again. 

2. Rewriting the code under test to implement the same functionality in a different way can invalidate assumptions built into the test. This can cause your tests to fail unnecessarily, and at worst, they can cause false positives and hide bugs in your code. This is because white-box tests are not written to test the intended behavior of the code, not just to force a particular implementation to do what it does.

3. White-box testing complicates testing because the tester must know about the program or the test team needs at least one good programmer who can understand the program at the code level. Increase. White-box testing requires highly-skilled programmers due to the complexity of the tests to be performed. 

4. In some cases, it is not practical to test all existing conditions of the application and some conditions are not tested. 

5. The tests focus on the current state of the software and may not detect missing features.

Testing Techniques and Code Coverage

1. Statement coverage

This measure helps you identify faulty programming logic within your programs. You should perform a statement coverage check for security purposes- especially when processing data from external sources or user input. Statement coverage is a white-box testing technique that ensures that every executable statement in your code is executed and tested at least once. For example, suppose a code block contains multiple conditions, each used for a specific range of inputs. In that case, the test executes each range of inputs to ensure that all lines of code are actually executed. Instruction coverage helps reveal unused instructions, new branches, missing instructions referenced by some code, and dead code left over from previous versions. Branch coverage. While generating black box code, check for missing statements that may impact program execution, such as variable initialization or method calls. For example, if you are checking variable declaration coverage, you should also ensure each variable has at least one declared use within your code.

2. Branch coverage

The branch coverage check looks for all possible branches in your code that lead to different states in your program. It helps you find defects while processing specific instructions or data in your program. Branch coverage maps your code to branches of conditional logic, ensuring each branch is covered by unit tests. 

For example, if you have multiple nested conditionals: A, C, and D are conditional branches because they only occur if the condition is met. B is an unconditional branch because it always executes after A. In the branch coverage approach, the tester identifies all conditional and unconditional branches and writes code that takes as many branches as possible.

3. Path coverage 

Path coverage checks for all possible paths in your code that lead to a particular state in your program. This includes your program’s beginning, intermediate, and end states. Path coverage deals with linearly independent paths through your code. The tester draws a control flow diagram of your code, as in the example below. Control flow diagram used to design tests with path coverage approach There are several possible paths through the code in this example. 

• 1, 2 
• 1, 3, 4, 5, 6, 8 
• 1, 3, 4, 7, 6, 8
• 6, 3, 4, 5, 6, 8 etc 

Tester writers run unit tests in the path-coverage approach to take as many paths as possible through the program’s control flow. The goal is to identify wrong, redundant, or inefficient paths.

Types of White box testing

1. Unit Tests 

Unit tests are often the first application tests run. As each unit or block of code is developed, it is unit tested. Programmers are primarily responsible for unit testing. Software developers write a few lines of code, a single function or object, test it to ensure it works, and then move on to the next step. In the early stages of the software development lifecycle, unit tests help identify most problems. Errors discovered at this stage are inexpensive and easy to fix. Errors identified at this stage are inexpensive and easy to fix

2. Test for memory leaks

Memory leaks are one of the most common causes of slow-running apps. If you have slow-running software applications, you need a QA expert who knows how to detect memory leaks. QA experts are skilled in finding memory leaks, which is essential when software applications run slowly.

3. White Box Penetration Testing 

This type of testing gives the tester/developer access to the entire source code of the program, as well as extensive network information, her associated IP address, and all server information. The goal is to attack the code from multiple sides to uncover security gaps. White Box Mutation Testing – White box mutation testing is widely used to determine the best coding strategies for growing software solutions.

White Box Testing Tools

Below is a list of top white box testing tools.

• EclEmma
• NUnit
• PyUnit
• HTMLUnit
• CppUnit

Conclusion

Software developers must be knowledgeable about their programs if they want them to function properly and meet design goals in every scenario they throw at them. This applies to white box testing since developers must be knowledgeable about their programs if they want them to function properly and meet design goals in every scenario they throw at it- but it also applies to gray box testing since developers must be knowledgeable about their programs if they want them new ones to function properly and meet design goals in every scenario they throw at it. Knowing what you’re doing is crucial before writing any code and debugging any issues arising during development processes.