TestGen.SubstituteGenerator 1.0.2

TestGen.SubstituteGenerator

A powerful substitute generator for creating sociable test classes with deep dependency resolution using NSubstitute.

🚀 Features

• Deep Dependency Resolution: Recursively analyzes the entire dependency tree (Controller → Manager → Service → Repository)
• Generic Type Support: Full support for generic interfaces like IRepository<T>, IService<TIn, TOut>
• Accurate Mock Setup: Analyzes actual interface methods to generate precise SetupDefaults() configurations
• Smart Return Values: Intelligent default return value generation for async methods, collections, primitives, and complex types
• File Generation: Creates substitute class files directly to specified directories
• C# Naming Conventions: Proper PascalCase property naming following C# standards

📦 Installation

dotnet add package TestGen.SubstituteGenerator

🎯 Usage

Basic Usage

using TestGen;
using YourApp.Controllers;

// Generate substitute class content
var substituteCode = SubstituteGenerator.GenerateSubstituteClass(typeof(UserController));

// Or create the file directly
SubstituteGenerator.GenerateSubstituteClass(typeof(UserController), "./Tests/Substitutes");

Example Generated Substitute

For a UserController with dependencies on IUserService, IEmailService, and ILoggerService, the generator creates:

public class UserControllerSubstitute
{
    // All dependencies across the entire tree
    public IUserService UserService { get; }
    public IEmailService EmailService { get; }
    public ILoggerService LoggerService { get; }
    public IUserRepository UserRepository { get; }  // From UserService dependencies
    public IAuditService AuditService { get; }      // From UserService dependencies
    
    public UserController Controller { get; }

    public UserControllerSubstitute()
    {
        // All mocks initialized
        UserService = Substitute.For<IUserService>();
        EmailService = Substitute.For<IEmailService>();
        // ... etc
        
        Controller = new UserController(UserService, EmailService, LoggerService);
    }

    public void SetupDefaults()
    {
        // Accurate method-specific setups based on actual interface analysis
        UserService.GetUserByIdAsync(Arg.Any<int>()).Returns(Task.FromResult((User?)null));
        EmailService.ValidateEmailAsync(Arg.Any<string>()).Returns(Task.FromResult(true));
        // ... etc
    }
}

🧪 Sociable Testing

The generator enables true sociable testing where:

✅ Business logic flows through all application layers
✅ Only external dependencies (database, network, etc.) are mocked
✅ Fast, reliable test execution without external calls
✅ Comprehensive coverage of dependency interactions

🔧 Advanced Features

Generic Type Support

// Handles generic interfaces automatically
IGenericRepository<User> → GenericRepositoryUser
IDataService<string, int> → DataServiceStringInt
IValidator<CreateUserRequest> → ValidatorCreateUserRequest

Smart Default Generation

// Async methods
Task<User> → Task.FromResult(new User())
Task<bool> → Task.FromResult(true)
Task → Task.CompletedTask

// Collections
IEnumerable<User> → new List<User>()
Task<IList<Product>> → Task.FromResult(new List<Product>())

// Primitives
bool → true, int → 0, string → ""

📖 Documentation

Visit our GitHub repository for full documentation, examples, and contribution guidelines.

📄 License

This project is licensed under the MIT License.