Mock CloudBlobClient with AutoFac and AutoMock

Question

I\'m trying to write unit tests for my AzureBlobRepository. The repository receives a CloubBlobClient in the constructor. I want to mock the client, but this gives an except

Answer 1

I have managed to mock it using NSubstitute, i have only mocked the functions that i use.

/// 

/// Create a mock for CloudBlobClient
/// 
/// 
/// 
private CloudBlobClient GetMock(bool containerExists = true)
{
    var items = new List();
    var client = Substitute.For(new Uri("http://foo.bar/"), null);
    var container = Substitute.For(new Uri("http://foo.bar/"));
    client.GetContainerReference(Arg.Any()).Returns(container);
    container.ExistsAsync(Arg.Any()).Returns(Task.FromResult(containerExists));
    container.ListBlobsSegmentedAsync(Arg.Any(), Arg.Any(), 
                                        Arg.Any(), 
                                        Arg.Any(), 
                                        Arg.Any(), 
                                        Arg.Any(), 
                                        Arg.Any(), 
                                        Arg.Any())
                                        .Returns(ci => new BlobResultSegment(items.ToArray(), null));

    container.GetBlockBlobReference(Arg.Any()).Returns(ci => GetBlockBlobMock(ci.ArgAt(0), items));
    return client;
}

/// 

/// Create a mock for CloudBlockBlob
/// 
/// 
/// 
/// 
private CloudBlockBlob GetBlockBlobMock(string name, List listBlobItems)
{
    var created = DateTimeOffset.Now;
    var bufferStream = new MemoryStream();
    var blob = Substitute.For(new Uri("https://foo.blob.core.windows.net/bar/" + name + ".txt"));
    //We can't mock the value the normal way, use reflection to change its value!
    blob.Properties.GetType().GetProperty(nameof(blob.Properties.Created)).SetValue(blob.Properties, created);
    //we cant mock properties! (Dam this wont work)
    blob.UploadFromStreamAsync(Arg.Any(),
                                Arg.Any(),
                                Arg.Any(),
                                Arg.Any(),
                                Arg.Any()).Returns(ci => {
                                    var stream = ci.Arg();
                                    stream.CopyTo(bufferStream);
                                    listBlobItems.Add(blob);
                                    return Task.CompletedTask;
                                });

    blob.DownloadToStreamAsync(Arg.Any(),
                                Arg.Any(),
                                Arg.Any(),
                                Arg.Any(),
                                Arg.Any()).Returns(ci =>
                                {
                                    var stream = ci.Arg();
                                    bufferStream.Position = 0;
                                    bufferStream.CopyTo(stream);
                                    stream.Position = 0;
                                    return Task.CompletedTask;
                                });
    return blob;
}

I'm not 100% sure its 100% accurate but it allows me to run some unit tests!