How To Write A Test Cases In Software Testing?

In 2012, Amazon faced a major issue during a sales event when prices on their website became wildly incorrect. This chaos was due to poorly written test cases that failed to catch critical bugs in the pricing algorithm. This costly mistake highlights the importance of well-crafted test cases in software testing. Properly written test cases ensure thorough testing, preventing errors, and maintaining a reliable user experience.

In this blog, we will show you how to write effective test cases with practical examples to help ensure your software's quality and reliability.

Test cases in software testing are a set of instructions that define the steps to verify a software system meets its requirements. They're essential for software testing, serving as blueprints for testers to evaluate specific features and functionalities. Each test case includes an ID, description, preconditions, steps, data, and expected result. By executing these test cases, testers can identify defects, ensure quality, and validate software behavior. Effective test cases are crucial for detecting bugs early, preventing costly errors, and maintaining a reliable app. In fact, a study by the International Institute for Software Testing found that 70% of software defects are caught during the testing phase, thanks to effective test cases.

What is Test Cases in Software Testing?

A test case is a collection of inputs, operations, or actions that have to be performed in order to check if a system satisfies specified requirements. It is a particular event or approach that has been developed to check one part of the software, for instance, a characteristic, functionality, or a glitch.

Types of Test Cases

1. Functional Test Cases: These test cases target the functionality of the software that involves testing its ability to perform a set of tasks, which any good software ought to perform.
2. Non-Functional Test Cases: These are application-specific test cases that are directed towards testing various non-functional software attributes, including speed, protection, attractiveness, and robustness.
3. Positive Test Cases: The simplest of these test cases include testing the software with proper inputs and their corresponding returns to ensure that the program works correctly as planned in standard conditions.
4. Negative Test Cases: These test cases are concerned with analyzing the software product with wrong inputs, mistakes, or abnormal conditions, then validate whether the software product handles mistakes and exceptions well.
5. Boundary Value Analysis (BVA) Test Cases: These are tests that are performed on the application on the edge between accepted values and the value outside range, which helps ascertain if the application will respond as required when placed at the boundary.‍
6. Equivalence Partitioning Test Cases: These test cases contain the data partitioning process where all the possible partitions of the input data feed into the method and then check that the software functions properly for all feeds.

Importance of using different types of test cases

Using different types of test cases ensures comprehensive testing of software, covering both functional and non-functional characteristics. This approach guarantees thorough testing from design to development stages, ensuring the software meets all standard requirements. By combining test cases, testers can confidently declare that the software is well-tested and meets all requirements.

• Enforce that the final software is functioning as per requirement and desired.
• Therefore, the goal of updating the software is to apply the gathered data to enhance its reliability, performance, and usability.
• Minimise on possibility of having defects and errors in the production phase
• It was giving confidence in the quality and reliability of the software to the users.

Why Write Effective Test Cases?

It is crucial to note that for a software application to be as effective and as efficient as is needed, it is imperative that well-developed test cases be made. Here are some reasons why writing effective test cases is crucial:

1. ‍Ensures Compliance: Test cases help to identify smaller irregularities and guarantee compliance with standards and legislation requirements.
2. ‍Reduces Bugs and Defects: One of the most important tools in most programming projects is the test case, which is used to find and fix problems before they affect the production environment.
3. ‍Improves Product Quality: Testing services help to emphasize that the software product meets the respective standard, thus increasing its quality and reliability if necessary.
4. ‍Faster Development Cycles: Efficient test cases help the testers to improve and update it frequently, which constitutes to the decreased required amount of time in the cycle of development.
5. ‍Improved Customer Satisfaction: The software test results are aimed at delivering better satisfaction and commitment of the target users by effective testing cases.
6. ‍Reduces Maintenance Costs: Test cases help to minimize those expenses that come with the reproduction of the test and the subsequent maintenance of various subsystems, components, and hardware and software technologies.
7. ‍Enhances Confidence: Test cases can be described as arrangements of test inputs and expected results that offer confidence in the quality and reliability of software with reduced risk of mistakes and/or faults.
8. ‍Supports Continuous Improvement: Integrated testing also shapes test automation for enhancing productivity and providing a structured avenue for ongoing enhancement of the software to fit the ever-changing demands of the users.
9. ‍Improves Collaboration: In the first place, the effective test cases enable coding teams, stakeholders, and customers to share information, lessening the risks of misunderstandings and conflict.
10. ‍Reduces Risk: Where many test cases are conducted correctly, the risk of failures in software, data loss, and security breaches is minimized, preserving user and organizational values.

Some Common misconceptions while writing about test cases, like:

• Time-consuming and not valuable
• Only necessary for critical features
• Can be done by testers themselves

How to Write Test Cases: A Step-by-Step Guide

The documentation of good test cases in software testing is one of the most important procedures that has to be done in the testing. This helps to find out that the software is of the specific quality that is expected, helps in controlling the number of bugs and defects, and results in high satisfaction levels for the customers. Of course, test case writing is a broad category of activities; let us move on to the steps of test cases in more detail:

Step 1: Identify Test Scope

• There is an identification of the different software features and functionalities that should be tested.
• Defining the scope of the synthesis to test In fact, the candidates will need guidance on the specifics of the requirements and restrictions to be tested.
• Develop a test plan for test case documentation that will help to format the test cases being written for the program.

Step 2: Determine the Test Case type

• Determine the test cases that will be necessary, including functional and non-functional tests; test with positive outcomes and test with negative outcomes.
• Prioritize the test case and establish which one or the test case should be executed first or should be given a higher priority.
• It is necessary to draw a test case matrix that would serve as the system for testing all the test cases and evaluating them.

Step 3: Write the Test Cases

• To improve the quality of the software testing, give easy and concise descriptions of test cases.
• Some of the most important information that is required when documenting a test case includes the inputs, expected output, and the pass and fail conditions.
• This method can be applied by preparing a template on what is required then filling as many boxes as possible with information from the interview.

Step 4: Review and Refine Test Cases

• Revise the test cases to ensure that the necessary inputs have been identified and tested, the values are realistic, and descriptions of each test case are clear.
• Make changes where necessary and finalize the test cases ensuring that they fit well with the test scope and the requirements.
• Suggest: Provide all the test cases to the development team and other stakeholders to ensure that everyone fully understands them.

Step 5: Execute the Test Cases

• Perform each test case as described in the test plan and in the sequence reported in the test plan.
• Document the test case results, status such as passed or failed, bug identified or encounter any problem during the test case execution.
• Make it a practice to document the results of a test case and present the report to the development team and stakeholders.

Step 6: Analyze and Result the Test Results

• After the completion of the test, one should examine the results with the intention of getting insights on the trends, patterns, and other characteristics that may be seen from the results with the intention of coming up with methodology of improving on it.
• Notifications with the results of the testing and with any defects or issues discovered should be forwarded to the development team and other stakeholders.
• Include a discussion of the result of the test as a means of developing programs that are of high quality.

Advanced Test Case Writing Techniques

Writing the test cases involves identifying the different test cases that should be performed on the software in order to verify if the software meets the necessary requirements and functionality. Here are some advanced test case writing techniques that can help you write more effective test cases:

1. Equivalence Partitioning: Split initial input data into the sets that define the expected behavior of the software. Equivalence class partitioning technique is used to check which test cases will capture all values and occurrences of the input. For example: Testing a login feature with different combinations of valid and invalid usernames and passwords.
2. Boundary Value Analysis: Identify which field in the input data is chosen for defining the input data range, and come up with several test cases that would show the minimum and the maximum of the range. This, in turn, ensures that we have a mechanism that checks how the software behaves outside the normal operating parameters range. For example, Testing a temperature conversion feature with temperatures at the minimum and maximum limits like, -273.15°C to 100°C.
3. Decision Table Testing: Use a table and write down several conditions, as well as the expected outcomes for complicated logical chains and making decisions. The decision table testing in software testing assists in incorporating all the likely scenarios and results within the test cases. For example, Testing a loan approval system with different credit scores, loan amounts, and income levels to determine the approval or rejection of the loan.
4. State Transition Testing: Enumerate all the various states that the software or software components can have and determine the test cases that validate the state transition. By using this technique, the necessary actions are guaranteed to be taken by the software during its state transformations. For example, Testing a banking system that transitions between different states like login, account creation,and transaction processing.
5. Use Cases: The first four principles are about identifying the main actors, objectives, and cases of the software and coming up with test cases that address these use cases. This technique assists in making a realization that the designed software facilitates the user's needs and expectations. For example, Testing a social media platform with different user scenarios, such as creating an account, posting a status update, and commenting on a post.

Manual vs Automation Test Cases

Manual Testing

Manual testing is a hands-on approach to software testing that relies on human intuition and observation skills, often without the aid of specialized tools. Crafting quality  test cases requires:

• Close attention to detail,
• Depth knowledge of the software needs to be tested, and
• Careful Planning

Here are some key points about manual testing:

1. Testers use test plans: These plans determine the activities and items that need to be tested and what is presumed from the testing process.
2. Focuses on user experience: Manual testing allows one to try how the software is going to be seen by an end user.
3. Not automated: Manual testing on the other hand does not involve using scripts unlike the case with automated testing and instead the tester interacts with the application.

These Steps follow for writing manual test case:

• Test Case ID: Unique identifier for the test
• Description: Brief explanation of what's being tested
• Steps: Numbered list of actions the tester will perform
• Expected Result: What should happen after each step
• Pass/Fail: Record the test outcome

Automation Testing

Automation testing is somewhat similar to manual testing, but there is no person testing the software, it is done with special tools. In their most basic form, these tests are scripts which pretend to be a user, performing specific actions and checking the results that the particular application being tested should provide.

Here are some key benefits of automated testing:

• Efficiency: Automated tests can be run much faster than manual tests, allowing for quicker feedback and faster development cycles.
• Accuracy: Automated tests follow a script precisely, eliminating human errors that can occur during manual testing.
• Repeatability: Automated tests can be easily repeated at any time, ensuring consistency in testing.
• Regression testing: Automated tests are particularly useful for regression testing, which involves verifying that new code hasn't introduced bugs into existing functionalities.

Automated test cases are similar to manual ones, but written for a testing tool to understand. Here's a simplified breakdown:

• Identify what to automate: Concentrate efforts on activities, which have high expectations and standards to be achieved in a day.
• Plan the steps: Ask yourself, what specific actions should the tool be able to do given the overlying set of functionality.
• Set verification points: Explain how the tool will monitor the execution of each step to ensure the correct results are generated.

Choose the tool's commands: Now employ the tool’s specific commands where you may be able to translate your operations into commands that the tool can execute.

Common Mistakes in Writing Test Cases

Some of the typical mistakes made while writing test cases are mistakes that occur while developing instructions that will be used to test a particular feature or functionality in software. Here are some of the most frequent pitfalls to avoid

• Lack of Clarity:  Unclear steps, expected results, or descriptions can lead to confusion and inconsistent testing.
• Insufficient Scope: Not having edge cases or fail cases can lead to faults that are not reached during testing, thus bugs are left unnoticed.
• Overly Specific: They may be highly effective when used to test a specific element of a program or software while at the same time being highly ineffective since they do not capture the efficiency and functionality of the feature as a whole.
• Poor Documentation: Lack of clear documentation can lead to a lack of understanding of the test case’s goal and practical application, and it may be very challenging for the next person in line who will be required to perform the test case.
• Not Considering Maintainability: This occurs especially when the test cases are hard to modify or update, thereby making them cumbersome as the software undergoes transformations.

Conclusion

In conclusion, it is worth noting that test cases effectively play a crucial role in determining the quality of the software. This paper aims to give a guideline for writing test cases which, if followed by the hire software testers, will guarantee coverage, comprehensiveness, clarity, and ease when maintaining the test cases. Understanding some of the mistakes that testers make when creating test cases, and their use of innovative test case writing styles, we can be assured that the created test cases will be useful in identifying misconduct and guaranteeing the end product’s quality. 

Alphabin can help you in the process of software testing by offering services in test case design, manual testing, and automation testing to ensure the users receive the best product that is of high quality and reliability.