generate-testability-wrappers

To mock static dependencies in C# unit tests, you can generate small wrapper interfaces and implementations around static calls like DateTime.Now or File.Exists, then register them via dependency injection to make the code test-friendly.

The best way to make untestable static C# code mockable is to extract the static calls into minimal abstraction interfaces covering only detected members, provide default implementations, and register them in your DI container.

Yes, this approach prefers guiding adoption of built-in abstractions like TimeProvider and IHttpClientFactory instead of generating redundant wrappers when they are available in your target framework.

You can generate DI-ready registration code for filesystem wrappers by specifying the filesystem static category and your preferred DI container, favoring System.IO.Abstractions for robust test doubles like MockFileSystem.

You need wrapper interfaces for static methods in C# when improving unit-testability for code using environment, console, process, time, or filesystem statics that are otherwise impossible to mock directly.

A limitation of wrapping static dependencies is that you must validate category and framework assumptions from your .csproj, and it produces only the abstraction surface required by detected call sites rather than a universal wrapper.