Springhard

`@WebMvcTest` vs `@SpringBootTest` — when to use which?

Answer

`@WebMvcTest` is a slice test: it loads MVC components (controllers, filters) and is fast, usually with mocked dependencies. `@SpringBootTest` loads the full application context and is better for integration tests, but slower.

Advanced answer

Deep dive

These two annotations trade realism for speed.

`@WebMvcTest`

Loads a **slice** of the context: MVC infrastructure + selected controller(s).
Great for testing routing, validation, serialization, status codes, and error mapping.
Typically uses `MockMvc` and mocks service dependencies (`@MockBean`).

`@SpringBootTest`

Boots the **full** application context.
Best for integration tests across layers (security, persistence, messaging).
Often paired with Testcontainers to run real dependencies.

Practical guidance

Use `@WebMvcTest` for controller-focused tests.
Use `@SpringBootTest` for end-to-end integration scenarios.
Consider other test slices: `@DataJpaTest`, `@JsonTest`, `@WebFluxTest`.

Common pitfalls

Using `@SpringBootTest` everywhere (slow suite, brittle tests).
Over-mocking in `@WebMvcTest` and missing real serialization/security issues.
Not importing/configuring security for slice tests (or disabling filters without realizing the coverage gap).