test-slice

Test Slice — Scaffold

A slice test loads only the beans for one layer, so it's fast and its failure points straight at that layer. Use the narrowest slice that still proves the behavior; only escalate to @SpringBootTest when the test genuinely spans layers (then see the integration-test skill for the Testcontainers full-stack case).

Step 1 — Pick the slice

• @DataJpaTest — repositories, entity mappings, custom queries. Loads JPA only, each test runs in a transaction rolled back at the end. Embedded DB by default; point it at real Postgres with @AutoConfigureTestDatabase(replace = NONE) + Testcontainers.
• @WebMvcTest(XController.class) — controller routing, JSON, validation, status codes, error mapping. Loads the MVC layer only; the service is a mock.
• Full @SpringBootTest — only when the behavior crosses controller → service → repository in one flow. Heavier; don't default to it.

Step 2 — Detect conventions

• Test framework: JUnit 5 + AssertJ assumed; match Mockito/Hamcrest if the project differs.
• Mock annotation by version: @MockitoBean (Spring Boot 3.4+) vs @MockBean (≤ 3.3, deprecated in 3.4). Check the Boot version and use the right one.
• Mirror the existing src/test/java package layout and naming (*Test under Surefire).

Step 3 — Render templates

From assets/, substitute {{PACKAGE}}, {{ENTITY}}, {{ENTITY_LOWER}}:

• DataJpaTest.java.tmpl → <pkg>/{{ENTITY}}RepositoryTest.java — autowires the repository + TestEntityManager, asserts with AssertJ.
• WebMvcTest.java.tmpl → <pkg>/{{ENTITY}}ControllerTest.java — MockMvc drives the controller, @MockitoBean {{ENTITY}}Service stubs the dependency, jsonPath checks the body.

Step 4 — Report

Created:
  src/test/java/.../<Entity>RepositoryTest.java   (@DataJpaTest, rolls back per test)
  src/test/java/.../<Entity>ControllerTest.java    (@WebMvcTest, MockMvc + mocked service)

State which slice(s) you generated and which mock annotation matches the Boot version.