C # - Mocking method for returning another value when called a second time using Moq

Question

I use Moq to fake the repository using the async method. This method should be called 2 times. The first time I call this method, I need to get a null value. Secondly, I need to get some parameter. If this method was not asynchronous, then I can use

 autoMockContext
            .Mock<IPopulationReadRepository>()
            .SetupSequence(method => method.GetCityForNewClients(It.IsAny<string>(), It.IsAny<string>(), It.IsAny<string>()))
            .Returns(null)
            .Returns(new Population { Id = 100, CityLongName = "Kharkiv, Kharkivska, Slobozhanshina" });

So the error is in the last line. The result should be like this:

 autoMockContext
            .Mock<IPopulationReadRepository>()
            .Setup(method => method.GetCityForNewClients(It.IsAny<string>(), It.IsAny<string>(), It.IsAny<string>()))
            .Returns(null);

 autoMockContext
            .Mock<IPopulationReadRepository>()
            .Setup(method => method.GetCityForNewClients(It.IsAny<string>(), It.IsAny<string>(), It.IsAny<string>()))
            .ReturnsAsync(new Entities.Zonning.Population { Id = 100, CityLongName = "Kharkiv, Kharkivska, Slobozhanshina" });

But do I need this in one call?

Answer 1

Thanks, I solved this problem

      autoMockContext
            .Mock<IPopulationReadRepository>()
            .SetupSequence(method => method.GetCityForNewClients(It.IsAny<string>(), It.IsAny<string>(), It.IsAny<string>()))
            .Returns(Task.FromResult<Entities.Zonning.Population>(null))
            .Returns(Task.FromResult(new Entities.Zonning.Population { Id = 100, CityLongName = "Kharkiv, Kharkivska, Slobozhanshina" }));