What testing frameworks does this skill support?

This skill is specifically optimized for the .NET ecosystem using xUnit for testing and NSubstitute for mocking.

What is the Mock Boundary Rule?

It is a rule that requires you to mock only infrastructure (like DbContext, ILogger, or external APIs) while always using real domain entities and value objects.

Can I write production code before the test?

No. The core 'Iron Law' of this skill is that no production code is written without a failing test existing first.

How does it handle integration tests?

It guides the creation of a shared CustomWebApplicationFactory using SQLite in-memory with a kept-alive connection for reliable database state testing.

Why does it use NSubstitute instead of Moq?

NSubstitute is preferred for its cleaner syntax and because it avoids specific controversies associated with Moq's history.

.NET Test-Driven Development

Name: .NET Test-Driven Development
Author: fiatkongen

byfiatkongen

0•

Security & Testing

Enforces a disciplined Test-Driven Development workflow for ASP.NET Core and EF Core projects using xUnit and NSubstitute.

This skill implements a strict Red-Green-Refactor cycle for .NET developers, ensuring high code quality and verified requirements from the first line of code. It provides domain-specific guidance on mocking boundaries—mandating real domain objects while mocking infrastructure—and standardizes behavioral test naming conventions. By prohibiting production code without a preceding failing test, it eliminates technical debt at the source and guides users through complex integration testing patterns using SQLite in-memory providers instead of less reliable alternatives.

Key Features

01Prevents common testing anti-patterns such as testing language features or getters/setters

02Implements the Mock Boundary Rule to protect domain logic integrity

030 GitHub stars

04Enforces strict Red-Green-Refactor cycles for all .NET development tasks

05Provides guidance for high-fidelity integration testing with SQLite in-memory

06Standardizes behavioral naming conventions for xUnit test suites

Use Cases

01Developing new ASP.NET Core features with guaranteed 100% test coverage

02Refactoring legacy .NET codebases by introducing disciplined testing patterns

03Implementing bug fixes that are verified by failing tests before implementation

What are Skills?·How to Install

Install with 🐟 Skill.Fish

npx skillfish add fiatkongen/saurun-marketplace dotnet-tdd

For use in Claude.ai and ChatGPT

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