Creating precise test cases and prioritizing them effectively

**Determining Test Coverage: What to Test and How to Prioritize**

In the previous post, we discussed testing strategies and the number of tests required to thoroughly test an application. However, it is equally important to determine what specific aspects of the application to test and how to prioritize them. In this article, we will explore three criteria that can help in defining test cases and understanding the level of detail needed for effective testing.

**Taking Care of the Happy Path**

The happy path refers to the most generic or primary user story of an application. It is the scenario where the user will quickly notice any errors or discrepancies. Testing this path ensures that the core functionalities of the application are working correctly. By focusing on the happy path, you can catch any major issues that may affect the user experience.

**Choosing the Level of Detail**

The level of detail in testing refers to the depth and comprehensiveness with which a use case is tested. It is important to consider the vulnerability of a use case and the potential impact of errors. If a use case is critical or prone to errors, it requires more detailed testing to ensure its reliability. On the other hand, less critical use cases can be tested with less detailed approaches.

**Prioritizing Lower-Level Tests**

When prioritizing tests, it is generally more efficient to start with lower-level tests such as unit and integration tests. These tests focus on individual components and their interactions, ensuring the individual parts of the application function correctly. By prioritizing these lower-level tests, you can catch and resolve issues early in the development process, reducing the likelihood of more complex problems in higher-level tests.

**Understanding Test Cases**

In software development, a test case is a series of actions or circumstances designed to verify the effectiveness of a software program or application. Test cases ensure that the software operates as intended and that all features and functions perform correctly. They are created by software testers or developers to ensure that the software meets the specified requirements.

When a test case is executed, the software performs various checks to ensure that the desired results are obtained. Test cases fulfill two primary tasks: verification and validation. Verification involves checking for errors and compliance with non-functional requirements, while validation ensures that the software meets high-level requirements and aligns with user expectations.

If a test case fails to produce the expected outcome, it serves as a notification of an unsuccessful result. The developer or tester must then investigate the issue and find a solution.

**Types of Test Paths**

Test cases can be derived from various scenarios, but there are three common types of test paths:

1. The Happy Path: This is the most common use case, where the software should function as intended. Testing the happy path ensures that the primary functionalities work correctly for the user.

2. The Scary Path: Also known as a negative test, this path focuses on scenarios that could cause the software to misbehave or enter an error state. It is particularly important to test these scenarios for highly vulnerable use cases that pose a high risk to stakeholders or users.

3. Other Paths: There are additional paths that can be considered for testing, although they are less commonly used. These paths include edge cases, stress testing, and boundary value analysis.

**Best Practices for Writing Test Cases**

To effectively write test cases, consider using the following patterns:

1. Arrange, Act, Assert Pattern: This pattern organizes tests into three distinct steps: arranging the test conditions, performing the test actions, and asserting the expected outcomes. It helps structure test cases and facilitates the creation of reusable tests.

2. Given, When, Then Pattern: Similar to the AAA pattern, this pattern focuses on the behavior-driven development approach. It divides tests into three steps: setting up the initial state, defining the actions, and specifying the expected results.

By following these patterns, test cases can be written in a structured and consistent manner, making them easier to understand and maintain.

**Example of a Classic Test Case**

Consider the following example of a classic test case:

In automated testing, documenting test cases in a table format may not be necessary. However, it is still beneficial to include the relevant information in the test itself. By paying attention to the test design, all the necessary information can be incorporated into the automated tests.

Test automation plays a crucial role in speeding up the testing process and ensuring accurate results. It allows for the execution of a large number of test cases efficiently, reducing the reliance on manual testing and minimizing the risk of human error.

**Conclusion**

By determining what aspects of an application to test, defining test cases, and prioritizing them, software development teams can ensure comprehensive test coverage and reduce the likelihood of critical issues. Using patterns for writing test cases and leveraging test automation further enhances the efficiency and accuracy of the testing process. Effective testing is essential for delivering high-quality software that meets user requirements and expectations.