@researchgate/react-intersection-list/lib/es/utils.js

React List Component using the Intersection Observer API

import warning from 'warning';
export function computeRootMargin(_ref) {
  var threshold = _ref.threshold,
      axis = _ref.axis;
  var margins = [threshold];
  var unit = threshold.match(/^-?\d*\.?\d+(px|%)$/) || [''];
  var value = "0" + unit.pop();

  if (axis === 'y') {
    margins.push(value);
  } else {
    margins.unshift(value);
  }

  return margins.join(' ');
}
export function getItemCount(_ref2, warnIfConflict) {
  var itemCount = _ref2.itemCount,
      items = _ref2.items;
  var hasItemCount = typeof itemCount !== 'undefined';
  var hasItems = typeof items !== 'undefined';
  var defaultValue = 0;

  if (warnIfConflict) {
    warning(!(hasItemCount && hasItems), 'ReactIntersectionList: cannot use itemCount and items props at the same time, choose one to determine the number of items to render.');
  }

  if (hasItemCount) {
    return itemCount;
  }

  return hasItems ? items.length || items.size || defaultValue : defaultValue;
}
export function computeSize(pageSize, itemCount) {
  return Math.max(0, Math.min(pageSize, itemCount));
}