public void GetNumbersAndAddThem_Execute() { // Arrange double[] numbersToUse = { 1, 2, 3, 4, 5 }; double expected = numbersToUse.Sum(); _mockIDbGetSomeNumbers.Setup(s => s.GetSomeNumbers()).Returns(numbersToUse); _mockNumberFunctions.Setup(s => s.AddNumbers(It.IsAny<double[]>())).Returns(expected); GetNumbersAndAddThem obj = new GetNumbersAndAddThem(_mockIDbGetSomeNumbers.Object, _mockNumberFunctions.Object); // Act var result = obj.Execute(); // Assert Assert.AreEqual(expected, result); }