Moq Class library

Question

I'm trying to find an appropriate way to Moq this, and I'm unsure on how to do it.This is a .Net Standard 2.0 library that must be consumed from .net 4.8, and .net core 3+.

Here is an Example.

private ILogService _logService;

public class Logger() :IProjectLogger
{
   _logService = new LogService();
}

When testing Logger(), I would like to Moq the ILogService methods. But since this may not always be used with dependency injection, and I don't want the client to have to inject ILogService, I'm stuck on how to moq ILogService methods when testing Logger()

Thanks!