public static void Pad_Row___Should_throw_ArgumentNullException___When_parameter_row_is_null()
        {
            // Arrange, Act
            var actual = Record.Exception(() => RowBaseExtensions.Pad((Row)null, 4));

            // Assert
            actual.AsTest().Must().BeOfType <ArgumentNullException>();
            actual.Message.AsTest().Must().ContainString("row");
        }
        public static void GetNumberOfColumnsSpanned___Should_throw_ArgumentNullException___When_parameter_row_is_null()
        {
            // Arrange, Act
            var actual = Record.Exception(() => RowBaseExtensions.GetNumberOfColumnsSpanned(null));

            // Act
            actual.AsTest().Must().BeOfType <ArgumentNullException>();
            actual.Message.AsTest().Must().ContainString("row");
        }