Android Unit Testing and Test Driven Development

Convert listed test cases into actual tests using test doubles like mocks and fakes. Inspect endpoint interactions, capture parameters, and validate auth token storage across success and error scenarios.

Practice using test doubles to test the FetchUserProfileUseCaseSync class in exercise four, following module instructions and description.txt, and compare with LoginUseCaseSync as a reference.

Explore how singletons share static state, causing cross-test interference and flaky tests that fail randomly. Learn why avoiding singletons improves unit testability and reliability.

Practice unit testing of the UpdateUsernameUseCaseSync with Mockito test doubles in the mockito-fundamentals module's exercise5, following description.txt instructions and spotting embedded bugs.

Differentiate objects from data structures by explaining why some dependencies are injected and others instantiated, relate this to the single responsibility principle, and show how test doubles support unit testing.

Leverage a generated test method template in Android Studio to automatically insert arrange, act, and assert comments, saving time while ensuring consistent test readability across the team.

Annotate tests with JUnit's @RunWith and use MockitoJUnitRunner to initialize mocks with @Mock, removing boilerplate.

Mockito is a versatile library for creating stubs and mocks with configurable doubles; use it for about 90 percent of tests, and fall back to manual doubles for complex needs.

Practice test-driven development by writing all tests upfront for exercise 6, implement FetchUserUseCaseSync, study @Nullable implications, and run instructor’s reference tests against your SUT.

Learn Uncle Bob's three rules for test driven development: don't write production code until a unit test fails, write tests to fail, and write only enough production code to pass.

Develop and test a fetch cart items use case that asynchronously retrieves items from a server, then notifies observers, using test-driven development, mocks, and observer pattern verification.

Master test driven development for Android unit testing by writing tests before production code, using Uncle Bob's granular technique for complex designs, and balancing pragmatism with build-time limits.

The lecture demonstrates that Android-dependent classes can be unit tested using a Context proxy and test doubles, debunking the myth and guiding test-driven development with mocks.

Expose the major challenges of unit testing in Android by showing how Activity inheritance blocks test doubles, yields massive framework code, and prevents full coverage in practice.

Explore how unit testing applies to a real Android app, the Stack Overflow browser, by testing narrowly defined classes while the UI layer remains abstracted via MVC.

Develop unit tests for the FetchLastActiveQuestionsUseCase by mocking the endpoint, validating success and failure notifications to listeners, and exploring coverage and mutation testing concepts.

Practice unit testing time dependent functionality by implementing in-memory caching with timeout in FetchQuestionDetailsUseCase, using a global use case across question details screens, and refactoring tests under tdd guidelines.

Treat unit testing as a discipline aligned with test driven development and single responsibility principle. Use a pragmatic 0 or 1 rule: test all requirements for each unit, avoid dogmatism.