JUnit Tips & LeetCode Tests

This repository contains examples and tests showcasing various JUnit tips and tricks, plus a collection of LeetCode solution tests. It is intended as a learning and reference project for writing tests, using test lifecycle controls, ordering, and simple in-memory test doubles.

Project layout (important folders):

• src/main/java/forJunitInTesting — example services, models, and a simple in-memory UsersDatabase implementation used by tests.
• src/test/java/junitPerks — JUnit examples demonstrating lifecycle annotations, ordering, and test instance behavior.
• src/test/java/leetCodeSolutionsTests — unit tests for LeetCode problem solutions.
• src/main/proto and src/main/resources — supporting resources and proto definitions.

Key examples and focus areas:

• Using @TestInstance, @BeforeAll, @AfterAll, @BeforeEach, @AfterEach.
• Ordering tests with @TestMethodOrder and @Order.
• Using simple in-memory test doubles (UsersDatabaseMapImpl) to avoid external dependencies.
• Writing targeted unit tests for algorithmic problems (LeetCode) to validate correctness and edge cases.

How to run tests (Windows):

1. Open a terminal in the project root (or use IntelliJ IDEA).
2. Use Gradle wrapper:
   • Run all tests:

     .\gradlew test
     

   • Run a specific test class:

     .\gradlew test --tests "junitPerks.UserServiceImplTest"
     

   • Run tests with more logging:

     .\gradlew test --info
     

IntelliJ IDEA:

• Import the project as a Gradle project.
• Use the IDE test runner to run individual tests or test classes from src/test/java.

Notes:

• Tests and examples are written in Java (project can include Kotlin/Gradle settings).
• Tests are designed to be self-contained and run quickly without external services.
• Review src/test/java/junitPerks/UserServiceImplTest.java for a representative example of lifecycle and ordered tests.

License:

• No license specified. Treat code as example material for learning.