Function stringify

csv/stringify.ts:428–467

(
  data: readonly DataItem[],
  options?: StringifyOptions,
)

 * @returns A CSV string.
 */
export function stringify(
  data: readonly DataItem[],
  options?: StringifyOptions,
): string {
  const { headers = true, separator: sep = ",", columns = [], bom = false } =
    options ?? {};

  if (sep.includes(QUOTE) || sep.includes(CRLF)) {
    const message = [
      "Separator cannot include the following strings:",
      '  - U+0022: Quotation mark (")',
      "  - U+000D U+000A: Carriage Return + Line Feed (\\r\\n)",
    ].join("\n");
    throw new TypeError(message);
  }

  const normalizedColumns = columns.map(normalizeColumn);
  let output = "";

  if (bom) {
    output += BYTE_ORDER_MARK;
  }

  if (headers && normalizedColumns.length > 0) {
    output += normalizedColumns
      .map((column) => getEscapedString(column.header, sep))
      .join(sep);
    output += CRLF;
  }

  for (const item of data) {
    const values = getValuesFromItem(item, normalizedColumns);
    output += values
      .map((value) => getEscapedString(value, sep))
      .join(sep);
    output += CRLF;
  }

  return output;
}