Mocking Datasets with Moq

Question

I'm trying to get started with Moq and having trouble finding any good resources to do what I need.

I have a Data Interface class that has a Get method which returns a Dataset via Stored Procedure. This is the way the code was written and I can't change it at the moment so it has to be done this way.

I want to test this class by Mocking the Dataset and returning data so I don't have to actually make a database call.

Is anyone doing this and if so where is a good place to get started doing it?

Answer 1

You don't need a database connection to fill in a DataSet. You can mock it like this:

IDataInterface di = new Mock<IDataInterface>();
DataSet mockDataSet = CreateMockDataSet();
di.Expect(x => x.Get()).Returns(mockDataSet);
something.UseDataInterface(di.Object);

Filling in a mock DataSet is quite painful, though. If I'm doing this, I generally put a facade interface in front of the returned DataSet, which is easier to mock. Or I change the code to use a DataTable, which is easier to fill in.

Alternatively, use an embedded database, such as SQLite or SQL Server CE, for your unit tests.