tdd-dotnet

name	tdd-dotnet
description	Implement a .NET feature using strict Red-Green-Refactor TDD with xUnit, FluentAssertions, and Moq for PlaylistMiner backend.

TDD Feature Implementation (.NET)

Implement the requested feature using strict Red-Green-Refactor TDD.

Step 1: Red — Write Failing Tests

1. Create test class in tests/PlaylistMiner.UnitTests/ matching the source file path
2. Name tests: Test_MethodName_Scenario_ExpectedResult
3. Use FluentAssertions: .Should().Be(), .Should().Contain(), .Should().Throw<>()
4. Use Moq for dependencies: var mock = new Mock<IService>()
5. Follow Arrange-Act-Assert pattern
6. Run dotnet test — confirm tests FAIL

Step 2: Green — Minimal Implementation

1. Write the minimum code to make tests pass
2. No refactoring, no optimization, no extras
3. Run dotnet test — confirm tests PASS

Step 3: Refactor

1. Clean up implementation keeping tests green
2. Extract interfaces, simplify, reduce duplication
3. Run dotnet test — confirm tests still PASS

Rules

• NEVER write implementation before the test
• All async methods accept CancellationToken
• Return DTOs from Core project, never EF entities
• Use [Category("Unit")] for unit, [Category("Integration")] for integration tests
• Integration tests use Testcontainers with real PostgreSQL