Problem with Moq Returns() and FromResult() methods-CodePudding

I'm working on a MSTest project which has a reference to a .NET 6.0 project.

I'd like to use Moq for constructing unit tests.

In my .Net project I have an interface IDataAccees with a method declaration which has the following signature:

Task<(TypeA, Resource[,])> LoadAsync(Int32 size);

FileDataAccess class implements this interface. Inside the class definition there's the LoadAsync implementation as well.

public async Task<(TypeA, Resource[,])> LoadAsync(Int32 size)
{
   ...
}

private fields in my UnitTest.cs file:

private Resource[,] _mockedTable = null!; 
private Mock<IDataAccess> _mock = null!;
private TypeA _a = null;

I'd like to correct / complete the statement _mock.Setup(...) seen below inside my Unittest.cs file in order to establish the appropriate Moq-management of my LoadAsync() method, however I have doubts about this.

_mockedTable = new Resource[100, 100];

_mock = new Mock<IDataAccess>();

_mock.Setup(mock => mock.LoadAsync(It.IsAny<Int32>()))
                .Returns(() => Task.FromResult( ));

CodePudding user response：

Assuming that you want to return the _mockedTable object from your mocked class, you could do this:

_mock.Setup(mock => mock.LoadAsync(It.IsAny<Int32>()))
    .ReturnsAsync((new TypeA(), _mockedTable));

CodePudding user response：

Constructing the response

var response = new ValueTuple<TypeA, Resource[,]>(_a, _mockedTable);

//OR simply just
var response = (_a, _mockedTable);

Setting up the mocked object

_mock.Setup(mock => mock.LoadAsync(It.IsAny<Int32>()))
     .ReturnsAsync(response);

//OR in case moq with version greater than 4.16
_mock.Setup(mock => mock.LoadAsync(It.IsAny<Int32>()).Result)
     .Returns(response);