Mocking Newtonsoft.Json 单元测试时

Question

I'm currently testing a class that reads an embedded json file, deserialises and loads it into my DI container. Here is a tl;dr of the code, omitting error handling:

private readonly IAssemblyManager _assemblyManager;
private readonly IContainerRegistry _containerRegistry

public void Load(string resourceName)
{
    string json = _assemblyManager.LoadResource(resourceName);

    IConfiguration config = JsonConvert.DeserializeObject<Configuration>(json);

    _containerRegistry.RegisterInstance<IConfiguration>(config);
}

I'm using NUnit and Moq to test and I'm fairly new to the testing game. I want to know the best approach to testing the JsonConvert method, I've had to write wrappers for some of my tests but would be absolutely devastated if I had to do it here. This is the most downloaded NuGet package, surely people have come across this issue and have a decent solution. I've used System.IO.Abstractions to allow me to test my file access code, I would have expected there would be something similar for Newtonsoft.Json .

Other potential workarounds could be to have my assembly manager doing the deserialisation:

public interface IAssemblyManager
{
    T LoadResource<T>(string resourceName);
}

But for my application I want to use the IAssemblyManager to load sql & json, I don't really want it being responsible for deserialising anything. And I've also just moved my problem from one class to another.

Answer 1

There is no official dependency injection package for Newtonsoft.JSON. To test your code, there is no way around creating wrappers, unless you find a mocking framework that mocks static methods.