tools/csvparser.js

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/**
 * Creates a CSV lines parser.
 */
function CsvParser() {
};


/**
 * A regex for matching a CSV field.
 * @private
 */
CsvParser.CSV_FIELD_RE_ = /^"((?:[^"]|"")*)"|([^,]*)/;


/**
 * A regex for matching a double quote.
 * @private
 */
CsvParser.DOUBLE_QUOTE_RE_ = /""/g;


/**
 * Parses a line of CSV-encoded values. Returns an array of fields.
 *
 * @param {string} line Input line.
 */
CsvParser.prototype.parseLine = function(line) {
  var fieldRe = CsvParser.CSV_FIELD_RE_;
  var doubleQuoteRe = CsvParser.DOUBLE_QUOTE_RE_;
  var pos = 0;
  var endPos = line.length;
  var fields = [];
  if (endPos > 0) {
    do {
      var fieldMatch = fieldRe.exec(line.substr(pos));
      if (typeof fieldMatch[1] === "string") {
        var field = fieldMatch[1];
        pos += field.length + 3;  // Skip comma and quotes.
        fields.push(field.replace(doubleQuoteRe, '"'));
      } else {
        // The second field pattern will match anything, thus
        // in the worst case the match will be an empty string.
        var field = fieldMatch[2];
        pos += field.length + 1;  // Skip comma.
        fields.push(field);
      }
    } while (pos <= endPos);
  }
  return fields;
};