White Box Testing Example, Definition, and Methodologies

This article explains a white box testing example and its basic definitions along with the methods used for this testing technique in software projects.

What is White Box Testing?

A software testing method focuses on an application or system's internal architecture and operation. It is sometimes referred to as structural testing, transparent box testing, and glass box testing. The core code, architecture, and design of the software under test are all accessible to the tester during white box testing.


White box examples are studied to learn the importance and significance in a typical software project. White box testing's primary goal is to make sure that all of the software's internal parts operate properly and according to plan. It entails examining the code, comprehending its logic, and developing test cases by this comprehension. White box testing seeks to confirm the accuracy of certain functions, statements, and code routes. A typical White box testing routine employs the following methods:


1. Branch Coverage: All potential code branches and decision points are tested. Assuring that each branch is performed and acts, as predicted, is the aim.

2. Statement Coverage: With this technique, every statement in the code is intended to be tested at least once. All conceivable execution pathways and branching are included in the design of test cases.

3. Path Coverage: Testing all potential routes through the code, including loops and conditional expressions, is known as "path coverage." It guarantees that every logical path is examined.

4. Code reviews and inspections: In addition to automated testing, white box testing also involves manual code inspections and reviews. Developers and testers analyze the code to identify potential issues, code smells, or areas that require further testing.

5. Condition coverage: This technique focuses on testing all possible combinations of conditions within the code. It aims to verify that each condition evaluates to true and false at least once.

White Box Example:

Suppose we have a function called Prime () that checks whether a given positive integer is a prime number. The function is implemented as follows:


def isPrime(num):
    if num < 2:
        return False
    for i in range(2, int(num**0.5) + 1):
        if num % i == 0:
            return False
    return True


Now let's perform white box testing on this isPrime () function:


1. Statement Coverage:

    • Test Case 1: Pass 2 as the input and verify that the function returns True.
    • Test Case 2: Pass 10 as the input and verify that the function returns False.
    • Test Case 3: Pass a negative number as the input and ensure that the function returns False.

2. Branch Coverage:

    • Test Case 4: Pass a prime number (e.g., 13) and ensure that the function executes the branch for prime numbers.
    • Test Case 5: Pass a non-prime number (e.g., 15) and ensure that the function executes the branch for non-prime numbers.

3. Path Coverage:

    • Test Case 6: Pass a prime number and ensure that the function correctly identifies it as a prime number by completing the full loop without finding any factors.
    • Test Case 7: Pass a non-prime number and ensure that the function identifies it as a non-prime number by returning False when a factor is found.

4. Condition Coverage:

    • Test Case 8: Pass a perfect square of a prime number (e.g., 49) and verify that the function correctly identifies it as a non-prime number.


These test cases include prime numbers, non-prime numbers, negative numbers, and perfect squares to test various isPrime () function scenarios. We may assure thorough white box testing coverage by creating test cases that investigate multiple statements, branching, pathways, and situations within the code.

From the above white box testing example, we can deduce that white box testing enables testers to look into the software's internal workings, coding layout, and implementation specifics. This assists in confirming that the program operates properly at the individual component, statement, and path levels, ensuring that they all function as intended. White box testing gives testers access to internal code, allowing them to create test cases that cover all potential execution pathways, branches, and situations. This increases test coverage and lowers the possibility of undiscovered faults.

Through white box testing, performance bottlenecks, inefficient algorithms, or suboptimal code can be identified and optimized. Testers can analyze the code and suggest improvements to enhance the software's performance, scalability, and resource utilization.

Recommendation: WeTest Performance Testing

At WeTest, clients get superior services of white and black box testing along with well-crafted tools to help clients get various deep insights for their projects including PerfDog and PerfSight.

This article discussed the white box testing example and its basic concepts to conclude that white box testing plays a crucial role in thoroughly testing the internal components of the software. It helps in verifying the correctness of the code, identifying defects early, optimizing performance, improving code quality, and instilling confidence in the software's behavior.

Latest Posts
1Exploring Valuable Test Cases in the Android Official MVP Project: A Comprehensive Guide to Unit Tes This article serves as an appendix to "Interpreting the Unit Testing of the Android Official MVP Project". This MVP project and its unit testing cases can provide many insights for our work, so it is worth giving it a quick read.
2A Comprehensive Guide to XSS Attacks and Defenses This article provides a detailed introduction to XSS(Cross Site Scripting) vulnerability attacks and defenses, including vulnerability basics, XSS fundamentals, encoding basics, XSS Payload, and XSS attack defense.
3How to Make Your Go Program Run Faster? This article is about the Go language. It primarily focuses on runtime speed, rather than development speed – these two types of speed are distinct.
4Enhancing Mobile App Quality with Crowdsourced Testing: Benefits and Key Components In this article, we will explore the benefits of employing crowdsourcing for mobile app testing and discuss the key components that contribute to successful testing, including testing on different devices, languages, and locations.
5Video Game Testing: A Fun and Profitable Way to Make Money Playing Games In this article, we will explore various avenues through which you can potentially earn a substantial income by playing games, including creating guides, writing reviews, coaching and boosting, and game testing.