void expectedColumns_should_inferMaxFromFirstRow()
{
var tab = new PlainTextTable();
tab.ImportRows(create_test_data());
Assert.Equal(3, tab.ColumnsExpected);
}
void expectedColumns_should_throwExceptionIfRowElementLengthIsInvalid()
{
var tab = new PlainTextTable(4);
Assert.Throws <UnexpectedColumnCountException>(() => tab.ImportRows(create_test_data()));
}