7 Principles of Software Testing: Mastering the Foundations

An inevitable part of software development is its testing. Before the program reaches the audience, it should be examined for errors to provide the best user experience. Quality assurance (QA) teams discover whether the platform meets users’ needs and industry standards by implementing testing techniques into the software creation process.
That is why thoroughly investigating and fixing bugs in the early stages is the key to successful software development.

7 Principles of Software Testing

Every testing method comes with its rules and requirements. However, there are seven key principles of software testing that shape the general idea of testing. Adhering to these basics guarantees the success of a platform examination.

Principle 1: Testing Shows the Presence of Defects

It is wrong to admit that testing is intended to prove that software has imperfections. Instead, it is a process of identifying issues and documenting them. The earlier the errors are discovered, the more beneficial it is. Here is why:

• It prevents design and code defects. The development team follows the steps of software creation. However, they don’t cover the essential procedure of testing. When adding more features to the errorful platform, it will cause more trouble in debugging everything and can also put the whole process in danger.
• It saves time and money. Discovering issues in the early development stages is beneficial with a view to the future, as fixing errors at the final steps is much time and money-consuming.
• It improves communication with the team. Gathering around issues and brainstorming ideas for fixing them unite different team departments. Even before testing, when defining its objectives, the whole company is needed for making decisions.
• It increases the effectiveness of the software development life cycle (SDLC). Acting quickly when errors appear improves the development process and makes the team stick to deadlines and high-quality standards.

Even though the principle of testing is to identify defects, it doesn’t guarantee that the software will be of superior quality. Testing is the process of reducing, not eliminating, all the risks.

Principle 2: Exhaustive Testing is Impossible

Exhaustive testing refers to identifying all possible scenarios and user inputs to ensure software responds to all cases without errors. However, it is nearly impossible to obtain in reality. The concept of testing is to ensure that the platform works correctly according to the test requirements but can not guarantee that it will perform perfectly in all scenarios.

The test coverage identifies the area of software that will be tested. To reach maximum coverage, choosing the most suitable set of test cases is important. This will ensure the maximizing of defect detection.

As exhaustive testing is impossible, choosing what parts of the software need testing based on the potential risks is important. Risk-based testing (RBT) involves the estimation of the probability of risk. Under this technique, testers identify test case prioritization based on the potential impact on software quality.

Principle 3: Early Testing Saves Time and Money

Implementing testing techniques at the early development stage is one of the most important among test principles. As mentioned above, not only does it prevent you from debugging on the final stage but saves budget and time.

The concept of conducting testing early is inherent in shift left testing. Shift left refers to moving the testing practices as early as possible during the software development. These are the best techniques for implementing testing early:

• Prioritizing early involvement. The right tactic to implement testing is at the earliest stages. Software examination does not come after it is in the final development stages. Testers should be gathered around identifying user requirements and the scope of work to better understand the issues.
• Setting test-driven development (TDD). TDD approach refers to creating test cases by developers before writing code. This helps to identify user behavior and build development precisely on what users expect to receive from the software.
• Implementing continuous integration and continuous delivery (CI/CD) pipelines. Running automatic tests regularly ensures that the product continues to perform well after every code change or major update.

Even though early testing offers many advantages, it also comes with challenges. The most common ones are communication issues within the team, lack of resources, dealing with changes, missing documentation, an unstable environment, and the problem of test prioritization.

Principle 4: Defect Clustering

Defect clustering refers to the idea that a small number of issues cause the most major errors in the product. The defects tend to gather in one particular place or software module. But it is not an exception that they are located in different areas.

The reason for defect clustering occurring is that the issues are connected. For example, there is a defect in the authorization part that doesn’t allow users to log in, which causes a defect in access control. Another reason for defects gathering in one place is the software area’s criticality. If defects are present in critical areas, they have a larger impact on the product.

Defect clustering is important because it helps to identify the root of the problem and prevent the occurrence of similar issues in the future. It helps to prioritize efforts to fix major issues first. Also, testers can address several bugs in one fix by fixing some errors in one duster.

Principle 5: Pesticide Paradox

The definition of the pesticide paradox relates to the fact that conducting the same test regularly will not lead to discovering new defects. They will not be identified as new errors and, thus, will not be shown. The first reason why the pesticide paradox happens is because testers don’t update test cases after developers implement code changes. But even if this is not the case, it is still necessary to review the test cases.

These are the practices that help to keep the tests up-to-date:

• Keeping track of product changes. The previous test cases are considered ineffective once the slightest change has been implemented into the software. Thus, instead of writing new ones, try to create tests that can be corrected.
• Removing irrelevant tests. Once certain software functionality has been removed, it is time to remove the test cases. It also refers to the situation when, for example, all your tests didn’t detect any bugs. Some should be cut down, and others should be corrected.
• Adapting test data. As bugs are data-specific, modifying data in test cases, especially in automated ones, is important.

Principle 6: Testing is Context-Dependent

A principle that gets neglected the most among software testing principles is that testing depends on the content. QA specialists can’t apply the same testing techniques to an e-commerce platform or healthcare application because they have different functionalities.

Other context factors that should be considered are software difficulty, user expectations, and regulatory requirements. Testers will choose suitable tools, methods, and techniques based on these characteristics.

For example, when testing web applications, there is no need to test the battery power as they function only with an Internet connection. The techniques for web application examination include cross-browser testing, cookie file security, HTML/CSS verification, etc. For mobile applications, testers will choose to check installing and uninstalling on devices, network testing, battery usage, and compatibility.

Principle 7: Absence-of-Errors Fallacy

The principle to remember is that software testing doesn’t ensure it is completely bug-free. Along with errors, other aspects of the platform influence users’ satisfaction, like usability or accessibility. And they cannot be found by running test cases but by involving other specialists in product development.

The main idea of software testing is to minimize errors but not get rid of all of them, as it is nearly impossible. That is why setting realistic expectations for software quality and establishing clear acceptance criteria based on risk assessment and user requirements is important.

Conclusion

Software testing is a crucial step in the development process. However, to approach it properly, it is important to stick to the seven principles of software testing. They determine the main concept of testing and help to create a realistic picture of what to expect from a software examination.