midUnit Testing
What is dependency injection in testing?
Updated May 6, 2026
Short answer
DI allows passing dependencies instead of hardcoding them.
Deep explanation
It improves testability by allowing mocks or stubs to be injected.
Real-world example
Injecting mock API in service tests.
Common mistakes
- Tight coupling without DI.
Follow-up questions
- Why DI helps testing?
- Is DI always required?