Unit Testing Practices Quiz

1. What is unit testing?

• Unit testing is a method for analyzing user interfaces and designs.
• Unit testing is focused on the overall architecture of an application.
• Unit testing is the process of testing individual units of software in isolation.
• Unit testing is primarily used for performance optimization in software.

2. Why is unit testing important?

• Unit testing is only needed for large projects.
• Unit testing catches issues early in development.
• Unit testing replaces the need for integration testing.
• Unit testing eliminates all bugs in software.

3. What is the Arrange-Act-Assert (AAA) pattern in unit testing?

• The pattern involves three steps: Arrange, Act, and Assert.
• The pattern involves steps: Setup, Run, and Confirm.
• The pattern involves steps: Prepare, Test, and Check.
• The pattern involves steps: Select, Execute, and Validate.

4. How do you handle private methods in classes when it comes to unit testing?

• You should always declare private methods as public for testing purposes.
• Private methods cannot be tested and should be removed from the code.
• You can handle private methods by using reflection or by creating a public interface that allows access to the private method.
• Only test private methods by running the whole class in a separate test suite.

5. What is mocking in unit testing?

• Mocking is a technique used to simulate the behavior of external dependencies or objects that are difficult or impractical to use in a unit test.
• Mocking is about running tests without using any code dependencies whatsoever.
• Mocking refers to the act of executing tests in parallel to save time.
• Mocking is the process of replacing a real object with a fake one that only throws errors.

6. Why should unit tests be simple?

• Unit tests should be complex to cover all scenarios effectively.
• Unit tests should be simple to confuse the developers during testing.
• Unit tests should be complex to impress stakeholders with their thoroughness.
• Unit tests should be simple to ensure they are easy to write and maintain.

7. What is code coverage in unit testing?

• Code coverage is the number of test cases written per project.
• Code coverage is a metric that measures the amount of code executed by a test suite.
• Code coverage is the completeness of the documentation for the codebase.
• Code coverage is an index of the number of bugs found in the codebase.

8. How do you ensure unit tests are repeatable and scalable?

• Write tests that are automated and independent.
• Repeat the tests manually each time.
• Use manual testing methods for accuracy.
• Create large test files with multiple scenarios.

9. What is the Single Responsibility Principle (SRP) in unit testing?

• Each unit test should cover multiple functionalities at once.
• Each unit test should be independent of functionality tested.
• Each unit test should focus on testing a single piece of functionality.
• Each unit test should run only once during development.

10. Why should unit tests be automated?

• Unit tests should be only run before major releases to save time during the development.
• Unit tests should be automated to ensure they run frequently and provide immediate feedback, helping catch issues early in the development process.
• Unit tests should be designed to fail so that developers can find issues before the final product launch.
• Unit tests should be executed manually after each change to promote careful testing by developers.

11. How do you test asynchronous behaviors in unit tests?

• You can test asynchronous behaviors by only running tests in sequence without any delays.
• You can test asynchronous behaviors by measuring execution time and adjusting your code.
• You can test asynchronous behaviors using time-mocking libraries or frameworks that allow you to control and manipulate time within your tests.
• You can test asynchronous behaviors by ignoring the order of execution in your tests entirely.

12. What is the difference between stubbing and mocking?

• Stubbing is used for integration tests, and mocking is for unit tests.
• Stubbing and mocking are the same in unit tests.
• Stubbing returns predefined results, while mocking simulates behavior.
• Stubbing simulates behavior, while mocking returns predefined results.

13. Why should unit tests cover one scenario per test?

• To cover multiple scenarios at once for efficiency.
• To isolate specific program parts containing the issue when a test fails.
• To combine different functionalities in a single test case.
• To make test results more complex and informative.

14. How do you avoid test interdependence?

• Run tests in a random order.
• Write independent test methods.
• Use global variables for state.
• Combine all tests into one.

15. What is the purpose of parameterized tests in unit testing?

• To run tests in parallel without any inputs.
• To pass in different inputs and verify correct outputs.
• To automatically generate documentation for tests.
• To test global variables in isolation.

16. Why should unit tests be fast?

• Unit tests should be fast to reduce the overall number of tests needed for validation.
• Unit tests should be fast to allow teams to release code to production more frequently.
• Unit tests should be fast to ensure they can be run frequently and provide immediate feedback, helping catch issues early in the development process.
• Unit tests should be fast to consume less memory and improve system performance.

17. How do you ensure unit tests are simple and readable?

• Avoid comments to keep the code cleaner.
• Use complex assertions to cover many behaviors.
• Write all tests in one large function to save time.
• Use the AAA pattern and keep tests focused.

18. What is the role of code review in unit testing?

• Code review serves as a replacement for automation in unit testing.
• Code review is not related to unit testing and focuses solely on documentation.
• Code review is a method for managing software versions and releases.
• Code review helps assess the application code and tests together, providing insights into the code and its behavior, allowing improvements to be made.

19. Why should unit tests be deterministic?

• To ensure the same input always produces the same output.
• To allow for multiple concurrent tests to run.
• To avoid testing any external dependencies.
• To ensure tests run as slowly as possible.

20. How do you handle complex or external systems in unit testing?

• You disable all network calls and work with production data in your tests.
• You handle complex or external systems by using mocking frameworks to simulate their behavior, allowing controlled and repeatable testing without affecting the actual system.
• You write all tests manually to match every possible scenario for external systems directly.
• You ignore external systems altogether and focus solely on internal logic during unit testing.

21. What is the importance of focusing on critical components first in unit testing?

• It reduces the likelihood of significant issues.
• It ensures complete test coverage.
• It allows for more frequent failures.
• It increases code complexity.

22. Why should unit tests be independent of each other?

• To ensure test isolation for accurate results.
• To speed up the execution of tests overall.
• To make tests easier to understand for beginners.
• To reduce the size of test files.

23. What is the role of the testing pyramid in unit testing?

• The testing pyramid describes the desired distribution of test resources, with automated unit tests at the base, followed by integration and UI tests, and manual tests at the top.
• The testing pyramid focuses solely on manual testing methods for software.
• The testing pyramid makes unit tests more complex and less effective.
• The testing pyramid eliminates the need for integration testing completely.

24. Why should unit tests validate boundary conditions and corner cases?

• To eliminate the need for testing regular conditions.
• To avoid writing simple test cases for every scenario.
• To ensure the code behaves correctly under extreme conditions.
• To slow down the testing process for better accuracy.

25. How do you test for security issues in unit tests?

• You test for security issues by including security-related scenarios in your unit tests.
• You test for security issues by randomly running tests without any planning.
• You test for security issues by relying solely on user input for testing.
• You test for security issues by manually reviewing the entire code after testing.

26. How do you handle time-dependent behaviors in unit tests?

• You ignore time-dependent behaviors since they don`t affect unit tests.
• You postpone testing until the software is ready for production.
• You handle time-dependent behaviors using time-mocking libraries or frameworks that allow you to control and manipulate time within your tests.
• You manually adjust system time for each test case.

27. Why is it essential to use mocking frameworks in unit testing?

• It allows testing of external dependencies without real implementations.
• It is a method for visualizing code structure during testing.
• It increases the complexity of the test cases significantly.
• It generates random inputs for better coverage.

28. What are the risks of not writing unit tests?

• Faster development cycles
• Improved team communication
• Enhanced user interface design
• Increased bugs and technical debt

29. How does unit testing improve code maintainability?

• It allows developers to catch issues early, enhancing maintainability.
• It prevents all bugs from occurring in the application.
• It guarantees that all future code is error-free and perfect.
• It replaces the need for documentation in the codebase.

30. What types of assertions are commonly used in unit testing?

• Database assertions
• Performance assertions
• User interface assertions
• Equality assertions