---
name: GenerateUnitTest
description: Guide to creating isolated Unit Tests (high speed) using Mocking (Moq or NSubstitute).
---

# GenerateUnitTest Skill

When a user requests a **Unit Test** for a class/method, you must adhere to the following principles to generate the test code:

## Purpose
- Test solely one class/method in isolation.
- Completely ignore real Databases, Redis, or HTTP calls.
- Extremely fast execution speed.

## 1. For CQRS Handlers or Services
- **Identify Dependencies:** Automatically identify the Interfaces (e.g., `IRepository`, `IUnitOfWork`, `ILogger`, `IMediator`) injected into the constructor.
- **Create Mock Objects:** Use a Mocking library (like `Moq` or `NSubstitute`) to create fake instances of these Interfaces.
- **Test Scenario (Arrange - Act - Assert):**
  - **Arrange:** Provide fake data (Mock data) for the Interface methods.
  - **Act:** Call the method being executed (e.g., `Handle()` in CQRS or Service methods).
  - **Assert:** Check the returned result, OR verify if a Mock object's method was called the correct number of times (e.g., checking if `_repository.AddAsync()` was called), OR verify if it throws a `ValidationException` given invalid input.

## 2. For Domain Entities
- **Goal:** Verify internal business logic and calculations of the Entity.
- **Scenario:**
  - Initialize the Entity with specific states.
  - Call a method that alters the state or performs a calculation (e.g., `Order.CalculateTotal()`).
  - Verify if the modified value adheres to business rules (e.g., `Total` must equal `Price * Quantity`).

## Output File Format
- **Path:** Placed in the `tests/MyNewProjectName.UnitTests/...` project (corresponding to the tested class's root directory).
- **File Name:** `[ClassName]Tests.cs` (e.g., `CreateOrderCommandHandlerTests.cs`).
