unity-testability

To improve Unity testability, move domain logic into pure C# classes and use interfaces for dependency injection. This isolates logic from MonoBehaviour and scene state, creating clean seams for reliable unit tests.

EditMode tests run faster by validating pure C# classes outside the Unity runtime, while PlayMode tests execute MonoBehaviour behavior within the Unity engine. Isolating domain logic into plain C# classes enables both testing strategies with mocks.

Structure testable seams by extracting dependencies into interfaces and injecting them into pure C# classes. This minimizes reliance on scene state and allows you to inject mocks during EditMode and PlayMode tests.

Yes, you can refactor an existing Unity codebase by analyzing current MonoBehaviour scripts to identify boundaries, then moving domain logic into plain C# classes with mockable interfaces to enable reliable unit tests.

Unity unit tests fail when relying on scene state because MonoBehaviour dependencies are tightly coupled to the engine lifecycle. Isolating logic into pure C# classes removes scene state reliance and stabilizes test boundaries.

Avoid using MonoBehaviour for game logic when you need reliable unit tests and easier maintenance. Move domain logic to pure C# classes to isolate dependencies and clarify test boundaries for clean architecture.