android-unit-test

Android ViewModel unit testing involves structuring JUnit tests, mocking repository dependencies with MockK or Mockito, and asserting expected states. This ensures business logic stability and verifies data fetching behavior without requiring real data sources.

Testing Kotlin Coroutines and Flow in Android is best handled using Turbine utilities. This pattern allows you to collect and assert emissions from asynchronous streams, verifying that your repository and ViewModel Flow logic produces the correct sequential data.

Espresso instrumentation testing verifies UI interactions by launching your Android activity and simulating user actions like clicks and text input. This process asserts that the application's UI states update correctly in response to user behavior.

You can use Mockito and MockK for Android unit testing, though MockK is specifically designed for Kotlin and handles Kotlin-specific features better. Both frameworks provide patterns for mocking dependencies to isolate and test ViewModels and repositories effectively.

Parameterized tests for Android business logic run by feeding multiple input datasets into a single JUnit test structure. This allows you to verify various edge cases and logic branches comprehensively without duplicating test code for each scenario.