C# – Calling original method with Moq

cmockingmoq

I have a ProductRepository with 2 methods, GetAllProducts and GetProductByType, and I want to test the logic at GetProductByType. Internally, GetProductByType makes a call to GetAllProducts and then filters the correct ones.

public virtual IEnumerable<Product> GetAllProducts()
{
    //returns all products in memory, db etc
}

public virtual IEnumerable<Product> GetProductsByType(string type)
{
    return (from p in GetAllProducts() where p.Type == type select p).ToList();
}

So in my test I'd like to mock the call to GetAllProducts, so it returns a list of products defined at my test, and then call the original GetProductsByType, which will consume the mocked GetAllProducts.

I'm trying something like the code below but the original GetProductByType is not executed, it is mocked-out as well. In TypeMock I have a CallOriginal method that fixes this, but I can't figure it out with Moq. Any ideas?

var mock = new Mock<ProductRepository>();
mock.Setup(r => r.GetAllProducts()).Returns(new List<Product>() {p1, p2, p3});
var result = mock.Object.GetProductsByType("Type1");
Assert.AreEqual(2, result.Count());

Best Answer

Set CallBase to true on your mock. This will call the original virtual methods or properties if they exist, and haven't been set up to return a canned value.

var mock = new Mock<ProductRepository>() { CallBase = true };

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A demonstration of what happens when you get this wrong is here.

Best Answer

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