const search = /[\0\t\n\r]/g;
function preprocess() {
  let column = 1;
  let buffer = "";
  let start = true;
  let atCarriageReturn;
  return preprocessor;
  function preprocessor(value, encoding, end) {
    const chunks = [];
    let match;
    let next;
    let startPosition;
    let endPosition;
    let code;
    value = buffer + (typeof value === "string" ? value.toString() : new TextDecoder(encoding || void 0).decode(value));
    startPosition = 0;
    buffer = "";
    if (start) {
      if (value.charCodeAt(0) === 65279) {
        startPosition++;
      }
      start = void 0;
    }
    while (startPosition < value.length) {
      search.lastIndex = startPosition;
      match = search.exec(value);
      endPosition = match && match.index !== void 0 ? match.index : value.length;
      code = value.charCodeAt(endPosition);
      if (!match) {
        buffer = value.slice(startPosition);
        break;
      }
      if (code === 10 && startPosition === endPosition && atCarriageReturn) {
        chunks.push(-3);
        atCarriageReturn = void 0;
      } else {
        if (atCarriageReturn) {
          chunks.push(-5);
          atCarriageReturn = void 0;
        }
        if (startPosition < endPosition) {
          chunks.push(value.slice(startPosition, endPosition));
          column += endPosition - startPosition;
        }
        switch (code) {
          case 0: {
            chunks.push(65533);
            column++;
            break;
          }
          case 9: {
            next = Math.ceil(column / 4) * 4;
            chunks.push(-2);
            while (column++ < next) chunks.push(-1);
            break;
          }
          case 10: {
            chunks.push(-4);
            column = 1;
            break;
          }
          default: {
            atCarriageReturn = true;
            column = 1;
          }
        }
      }
      startPosition = endPosition + 1;
    }
    if (end) {
      if (atCarriageReturn) chunks.push(-5);
      if (buffer) chunks.push(buffer);
      chunks.push(null);
    }
    return chunks;
  }
}
export {
  preprocess
};
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