In this article, we learn what is Statement Coverage Testing, Which option will not be part of statement coverage testing, examples, and the advantages & disadvantages.
What is Statement Coverage Testing?
Statement coverage testing is a type of white-box testing that aims to measure the extent to which each statement in a program has been executed at least once during testing. The goal of statement coverage testing is to ensure that all statements in the code have been tested and that there are no dead or unreachable code segments that could potentially introduce errors.
To perform testing, a test suite is designed to execute each statement in the program at least once. The test cases are designed to exercise different paths through the code, including loops, branches, and conditional statements. The coverage metric is then calculated by dividing the number of executed reports by the total number of statements in the code.
While testing can provide valuable insights into the test coverage of a software application, it does not necessarily ensure that all possible program behaviors have been tested. This is because it is possible for two different input values to execute the same sequence of statements, which may lead to overlooking certain defects.
Therefore, testing should be complemented by other testing techniques such as branch coverage, path coverage, and decision coverage to achieve a higher level of confidence in the quality of the software application.
Which option will not be part of statement coverage testing?
All executable statements in the code should be part of statement coverage testing. Therefore, any option that does not involve testing all executable statements in the code would not be a part of statement coverage testing.
For example, options such as testing only a subset of statements, testing only the statements that are expected to fail, or testing only a specific part of the code would not be part of statement coverage testing. These options may be used in other types of testing, but not in statement coverage testing, which aims to test all executable statements in the code.
Statement Coverage Testing Example
Suppose we have the following code:
- def sum(a, b):
- result = a + b
- if result > 10:
- return “Result is greater than 10”
- return “Result is less than or equal to 10”
To perform statement coverage testing, we need to create a set of test cases that will execute each statement at least once. Here’s an example of three test cases:
Test Case 1:
This test case will execute lines 1, 2, 5, and 6. It will not execute line 3 because the result is less than or equal to 10.
Test Case 2:
This test case will execute lines 1, 2, and 3. It will not execute line 6 because the result is greater than 10.
Test Case 3:
This test case will execute lines 1, 2, 3, and 4. It will not execute line 5 because the result is greater than 10.
By executing these three test cases, we have covered all statements in the code. Test Case 1 covers lines 1, 2, 5, and 6. Test Case 2 covers lines 1, 2, and 3. Test Case 3 covers lines 1, 2, 3, and 4. Therefore, we can conclude that we have achieved 100% statement coverage testing for this code.
Note that achieving statement coverage testing does not necessarily mean that the code is free from defects. We also need to consider other types of testing, such as branch coverage testing and input validation testing, to ensure that the code behaves correctly under different conditions and scenarios.
Advantages of Statement Coverage Testing
- Helps in identifying dead code: Statement coverage testing helps in identifying any statements in the code that are not executed during testing. These statements are known as dead code and can be removed to improve the code’s readability and maintainability.
- Provides a metric for measuring test coverage: Statement coverage testing provides a metric for measuring how much of the code has been executed during testing. This metric can help in determining the quality of the test suite and identifying any areas of the code that require further testing.
- Improves code reliability: By testing all executable statements in the code, statement coverage testing helps in identifying any errors or defects that may have been introduced during the development process. This can help in improving the reliability of the code and reduce the likelihood of bugs in production.
- Helps in debugging: When a test fails during statement coverage testing, it provides a clear indication of which statement(s) in the code is causing the failure. This can help in quickly identifying and fixing the problem.
- Helps in compliance with industry standards: Many industry standards and regulatory bodies require that software applications undergo thorough testing, including statement coverage testing. By performing statement coverage testing, organizations can demonstrate their compliance with these standards and regulations.
Disadvantages of Statement Coverage Testing
- Does not guarantee complete testing: Statement coverage testing only ensures that each statement in the code is executed at least once during testing. However, it does not guarantee that all possible scenarios and input combinations have been tested. Therefore, it is possible to have code that has achieved 100% statement coverage but still contains defects.
- Focuses on code structure rather than behavior: Statement coverage testing focuses on testing each statement in the code, regardless of the behavior or outcome of the code. This means that it may not detect errors that are caused by interactions between different parts of the code or errors that occur during runtime.
- Ignores non-executable statements: Statement coverage testing only considers executable statements in the code and ignores non-executable statements such as comments, declarations, and whitespace. This means that code coverage metrics may be misleading and not accurately reflect the quality of the code.
- Can be time-consuming: Achieving 100% statement coverage testing can be time-consuming and may require many test cases. This can be impractical, particularly for complex software applications, where achieving 100% statement coverage may not be feasible.
- Can lead to over-reliance on coverage metrics: Focusing solely on achieving high statement coverage metrics can lead to over-reliance on the metrics and neglect other important testing aspects such as input validation, error handling, and security testing.