public void Next()
        {
            Mock<IRandomExtensions> randMock = new Mock<IRandomExtensions>();
            var target = new RandomDecimalDataSource(randMock.Object);
            target.Next(null);

            randMock.Verify(a => a.GetDecimal(System.Decimal.MinValue, System.Decimal.MaxValue), @"
            The GetDecimal method on the IRandomExtensions object was not called.
            ");
        }