generate-testability-wrappers

To make C# static dependencies mockable, you generate wrapper interfaces and default implementations for them, then register these wrappers with the dependency injection container. This allows mocking static calls during unit testing.

You generate testability wrappers for .NET static dependencies by running the skill with a static dependency category and target framework, like `generate-testability-wrappers time net8`, which outputs interfaces, implementations, and DI registration code.

.NET provides built-in abstractions for mocking static dependencies like DateTime by adopting features such as TimeProvider and IHttpClientFactory, which natively support dependency injection and testability without requiring custom wrappers.

The best way to register mockable interfaces with dependency injection in C# is to generate DI configuration code alongside the wrapper interfaces, ensuring the container maps the new abstractions to their default implementations automatically.

Yes, you need Microsoft.Extensions.DependencyInjection to create mockable wrappers for static C# code, because the generated DI registration code relies on this container to inject the wrapper interfaces into your .NET application.

You should create custom wrappers instead of using built-in .NET abstractions for testing when your static dependencies lack native alternatives, allowing you to generate tailored interfaces and implementations to replace untestable static calls.