How do you mock ILogger LogInformation

Question

I have a class that receives an ILogger and I want to mock the LogInformation calls but this is an extension method. How do I make the appropiate setup call for this?

Answer 1

ILogger is normally used thru extension methods, LogWarning, LogError, etc.

In my case I was interested in the LogWarning method which after looking at the code calls the Log method from ILogger. In order to mock it with Moq, this is what I ended up doing:

 var list = new List();
            var logger = new Mock();
            logger
                .Setup(l => l.Log(LogLevel.Warning, It.IsAny(), It.IsAny(), It.IsAny(), It.IsAny>()))
                .Callback(
                delegate (LogLevel logLevel, EventId eventId, FormattedLogValues state, Exception exception, Func formatter)
                {
                    list.Add(state.ToString());
                });