321-frameworks-spring-boot-testing-unit-tests

name	321-frameworks-spring-boot-testing-unit-tests
description	Use when you need to write unit tests for Spring Boot applications — including pure unit tests with @ExtendWith(MockitoExtension.class) for @Service/@Component, slice tests with @WebMvcTest and @MockBean for controllers, @JsonTest for JSON serialization. For framework-agnostic Java use @131-java-testing-unit-testing. Part of the skills-for-java project
license	Apache-2.0
metadata	{"author":"Juan Antonio Breña Moral","version":"0.13.0-SNAPSHOT"}

Spring Boot Unit Testing with Mockito

Apply Spring Boot unit testing guidelines with Mockito.

What is covered in this Skill?

• Pure unit tests: @ExtendWith(MockitoExtension.class), @Mock, @InjectMocks for @Service/@Component (no Spring context)
• Slice tests: @WebMvcTest, @MockBean for controllers
• @JsonTest for JSON serialization
• @TestConfiguration, @ActiveProfiles for test setup

Scope: Apply recommendations based on the reference rules and good/bad code examples. For integration tests use @322-frameworks-spring-boot-testing-integration-tests.

Constraints

Before applying any test changes, ensure the project compiles. If compilation fails, stop immediately. After applying improvements, run full verification.

• MANDATORY: Run ./mvnw compile or mvn compile before applying any change
• SAFETY: If compilation fails, stop immediately
• VERIFY: Run ./mvnw clean verify or mvn clean verify after applying improvements
• BEFORE APPLYING: Read the reference for detailed rules and good/bad patterns

When to use this skill

• Review Java code for Spring Boot unit tests
• Apply best practices for Spring Boot unit tests in Java code

Reference

For detailed guidance, examples, and constraints, see references/321-frameworks-spring-boot-testing-unit-tests.md.