Moq Params TargetParameterCountException : Parameter count mismatch Exception

Question

Following is my generic base repository interface

public interface IRepository<T>
{
    IQueryable<T> AllIncluding(params Expression<Func<T, 
                               object>>[] includeProperties);
}

my entity

public class Sdk 
{
    public Sdk()
    {
       this.Identifier = Guid.NewGuid().ToString();
    }

    public virtual ICollection<Resource> AccessibleResources { get; set; }

    public string Identifier { get; set; }    
}

and following is the specific repo

public interface ISdkRepository : IRepository<Sdk>
{
}

now I am trying to test a controller, using moq

Following is the code I am trying to test

public ActionResult GetResources(string clientId) {
        var sdkObject = sdkRepository
                           .AllIncluding(k => k.AccessibleResources)
                           .SingleOrDefault(k => k.Identifier == clientId);
        if (sdkObject == null)
            throw new ApplicationException("Sdk Not Found");
        return Json(sdkObject.AccessibleResources.ToList());
    }

using following test

[Test]
public void Can_Get_GetResources()
{
    var cid = Guid.NewGuid().ToString();
    var mockRepo = new Moq.Mock<ISdkRepository>();
    var sdks = new HashSet<Sdk>()
    {
        new Sdk()
        {
            Identifier = cid,
            AccessibleResources = new HashSet<Resource>()
            {
                new Resource()
                {
                    Id = Guid.NewGuid(),
                    Description = "This is sdk"
                }
            }
        }
    };
    mockRepo.Setup(k => k.
        AllIncluding(It.IsAny<Expression<Func<Sdk,object>>[]>()))
                       .Returns(sdks.AsQueryable);
    var sdkCtrl = new SdksController(mockRepo.Object);
    var returnedJson=sdkCtrl.GetResources(cid);
    returnedJson.ToString();
}

and it is throwing:

System.Reflection.TargetParameterCountException : Parameter count mismatch

Don't know why?

Answer 1

Though there is an answer marked as accepted, I believe there is a way to mock your repository correctly.

Instead of

mockRepo.Setup(k => k.AllIncluding(It.IsAny<Expression<Func<Sdk, object>>[]>()))
                     .Returns(sdks.AsQueryable);

please use

mockRepo.Setup(k => k.AllIncluding(It.IsAny<Expression<Func<Sdk, object>>[]>()))
                     .Returns((Expression<Func<Sdk, 
                        object>>[] includeProperties) => sdks.AsQueryable());

Answer 2

Another solution for solving this issue is to use: .AsQueryable() instead of .AsQueryable.