Write a string containing commas and double quotes to CSV

In my case, I didn't want to quote strings that did not need quoting. So I test the string for nasty characters before quoting it.

function escapeCSV (term) {
  if (term.match && term.match(/,|"/))  {
    return `"${term.replace('"','""')}"`
  } else {
    return term
  }
}

It turns out that, according to the CSV specs, to include double quotes within a string that is already quoted, you need to use two double quotes (""). I changed:

itemDesc = itemDesc.replace(/"/g, '\"');

to

itemDesc = itemDesc.replace(/"/g, '""');

I also removed

itemDesc = itemDesc.replace(/,/g, '\,');
itemDesc = itemDesc.replace(/'/g, '\'');

Since the column in the CSV is being quoted already. These are unnecessary.

I use this simple function to convert an string[][] to a csv file. It quotes the cell, if it contains a ", a , or other whitespace (except blanks):

/**
 * Takes an array of arrays and returns a `,` sparated csv file.
 * @param {string[][]} table
 * @returns {string}
 */
export function toCSV(table: string[][]) {
    return table
        .map(row =>
            row
                .map(cell => {
                    // We remove blanks and check if the column contains
                    // other whitespace,`,` or `"`.
                    // In that case, we need to quote the column.
                    if (cell.replace(/ /g, '').match(/[\s,"]/)) {
                        return '"' + cell.replace(/"/g, '""') + '"';
                    }
                    return cell;
                })
                .join(',')
        )
        .join('\n');
}