chore: publish from staged [skip ci]

plugins/java-development/commands/java-junit.md

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+---
+agent: 'agent'
+tools: ['changes', 'search/codebase', 'edit/editFiles', 'problems', 'search']
+description: 'Get best practices for JUnit 5 unit testing, including data-driven tests'
+---
+
+# JUnit 5+ Best Practices
+
+Your goal is to help me write effective unit tests with JUnit 5, covering both standard and data-driven testing approaches.
+
+## Project Setup
+
+- Use a standard Maven or Gradle project structure.
+- Place test source code in `src/test/java`.
+- Include dependencies for `junit-jupiter-api`, `junit-jupiter-engine`, and `junit-jupiter-params` for parameterized tests.
+- Use build tool commands to run tests: `mvn test` or `gradle test`.
+
+## Test Structure
+
+- Test classes should have a `Test` suffix, e.g., `CalculatorTest` for a `Calculator` class.
+- Use `@Test` for test methods.
+- Follow the Arrange-Act-Assert (AAA) pattern.
+- Name tests using a descriptive convention, like `methodName_should_expectedBehavior_when_scenario`.
+- Use `@BeforeEach` and `@AfterEach` for per-test setup and teardown.
+- Use `@BeforeAll` and `@AfterAll` for per-class setup and teardown (must be static methods).
+- Use `@DisplayName` to provide a human-readable name for test classes and methods.
+
+## Standard Tests
+
+- Keep tests focused on a single behavior.
+- Avoid testing multiple conditions in one test method.
+- Make tests independent and idempotent (can run in any order).
+- Avoid test interdependencies.
+
+## Data-Driven (Parameterized) Tests
+
+- Use `@ParameterizedTest` to mark a method as a parameterized test.
+- Use `@ValueSource` for simple literal values (strings, ints, etc.).
+- Use `@MethodSource` to refer to a factory method that provides test arguments as a `Stream`, `Collection`, etc.
+- Use `@CsvSource` for inline comma-separated values.
+- Use `@CsvFileSource` to use a CSV file from the classpath.
+- Use `@EnumSource` to use enum constants.
+
+## Assertions
+
+- Use the static methods from `org.junit.jupiter.api.Assertions` (e.g., `assertEquals`, `assertTrue`, `assertNotNull`).
+- For more fluent and readable assertions, consider using a library like AssertJ (`assertThat(...).is...`).
+- Use `assertThrows` or `assertDoesNotThrow` to test for exceptions.
+- Group related assertions with `assertAll` to ensure all assertions are checked before the test fails.
+- Use descriptive messages in assertions to provide clarity on failure.
+
+## Mocking and Isolation
+
+- Use a mocking framework like Mockito to create mock objects for dependencies.
+- Use `@Mock` and `@InjectMocks` annotations from Mockito to simplify mock creation and injection.
+- Use interfaces to facilitate mocking.
+
+## Test Organization
+
+- Group tests by feature or component using packages.
+- Use `@Tag` to categorize tests (e.g., `@Tag("fast")`, `@Tag("integration")`).
+- Use `@TestMethodOrder(MethodOrderer.OrderAnnotation.class)` and `@Order` to control test execution order when strictly necessary.
+- Use `@Disabled` to temporarily skip a test method or class, providing a reason.
+- Use `@Nested` to group tests in a nested inner class for better organization and structure.