Function moveCursor

lib/internal/readline/callbacks.js:61–86

* moves the cursor relative to its current location

(stream, dx, dy, callback)

 */

function moveCursor(stream, dx, dy, callback) {
  if (callback !== undefined) {
    validateFunction(callback, 'callback');
  }

  if (stream == null || !(dx || dy)) {
    if (typeof callback === 'function') process.nextTick(callback, null);
    return true;
  }

  let data = '';

  if (dx < 0) {
    data += CSI`${-dx}D`;
  } else if (dx > 0) {
    data += CSI`${dx}C`;
  }

  if (dy < 0) {
    data += CSI`${-dy}A`;
  } else if (dy > 0) {
    data += CSI`${dy}B`;
  }

  return stream.write(data, callback);
}

/**
 * clears the current line the cursor is on: