public void CallingIsNullAddsANullColumn()
        {
            var expressionMock = new Mock<DeleteDataExpression>();


            var builder = new DeleteDataExpressionBuilder(expressionMock.Object);
            builder.IsNull("TestColumn");

            var result = expressionMock.Object;
            var rowobject = result.Rows.First().First();
            rowobject.Key.ShouldBe("TestColumn");
            rowobject.Value.ShouldBeNull();

        }
        public void CallingIsNullAddsANullColumn()
        {
            var expressionMock = new Mock<DeleteDataExpression>();

            var builder = new DeleteDataExpressionBuilder(expressionMock.Object);
            builder.IsNull("TestColumn");

            var result = expressionMock.Object;
            IDataDefinition rowobject = result.Rows.First();

            Assert.IsInstanceOf<ExplicitDataDefinition>(rowobject);
            ExplicitDataDefinition rowDefinition = (ExplicitDataDefinition)rowobject;
            rowDefinition.Data.First().ColumnName.ShouldBe("TestColumn");
            rowDefinition.Data.First().Value.ShouldBeNull();
        }